SecProbe.io

<DOCUMENT>
<TYPE>TEXT-EXTRACT
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<FILENAME>filename2.txt
<TEXT>
 August 19, 2025

Gregory Weaver
Chief Financial Officer
Altimmune, Inc.
910 Clopper Road, Suite 201S
Gaithersburg, MD 20878

 Re: Altimmune, Inc.
 Form 10-K for the Fiscal Year Ended December 31, 2024
 File No. 001-32587
Dear Gregory Weaver:

 We have completed our review of your filings. We remind you that the
company and
its management are responsible for the accuracy and adequacy of their
disclosures,
notwithstanding any review, comments, action or absence of action by the staff.

 Sincerely,

 Division of Corporation
Finance
 Office of Life Sciences
</TEXT>
</DOCUMENT>

CORRESP
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 filename1.htm

 Altimmune, Inc. 910 Clopper Road, Suite 201S Gaithersburg, Maryland 20878 August 12, 2025 VIA EDGAR Division of Corporate Finance Office of Life Sciences U. S. Securities and Exchange Commission 100 F Street, N.E. Washington, D.C. 20549 Attention: Ms. Jenn Do Ms. Vanessa Robertson ​ Re: Altimmune, Inc. Form 10-K for the Fiscal Year Ended December 31, 2024 Form 10-Q for the Quarterly Period Ended March 31, 2025 File No. 001-32587 ​ Dear Ms. Do and Ms. Robertson: On behalf of Altimmune, Inc. (“Altimmune” or the “Company”), this letter is in response to your letter dated August 8, 2025 to Altimmune (the “Comment Letter”), relating to Altimmune’s Annual Report on Form 10-K for the fiscal year ended December 31, 2024 and Form 10-Q For Quarterly Period Ended March 31, 2025 (the “Q1 10-Q”). For ease of reference, the Staff’s comment is set forth in italic type immediately above the corresponding response submitted on behalf of Altimmune. Form 10-Q for the Quarterly Period Ended March 31, 2025 Management’s Discussion and Analysis of Financial Condition and Results of Operations, Page 13 Results of Operations, page 14 ​ 1. We note you have not broken out your research and development (R&D) expenses by product or category, unlike in the December 31, 2024 Form 10-K and the Forms 10-Q of 2024. Given R&D continues to account for most of your operating expenses and the expanded indications for pemvidutide, please provide revised disclosure to be included in future filings to quantify your direct R&D by product and indication for each period presented. As part of your response, please provide what this disclosure would have looked like had it been included in your March 31, 2025 Form 10-Q. ​ Response: We note the Staff’s comment and will include the requested disclosure in future filings. We refer the Staff to our Quarterly Report on Form 10-Q for the second quarter of 2025, filed on August 12, 2025 (our “Q2 10-Q”), which included the research and development expenses split out by categories, product and indication consistent with the request in this Comment Letter. See Results of Operations. Comparison of the three months ended June 30, 2025 and 2024 (p. 17 of our Q2 10-Q); Comparison of the six months ended June 30, 2025 and 2024 (p. 19 of our Q2 10-Q . In addition, we have set forth below the requested revised disclosure for the Q1 10-Q: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31,  ​ ​      2025      2024      Increase (Decrease)   Pemvidutide ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ MASH ​ $ 6,317 ​ $ 8,737 ​ $ (2,420)   (28) % Alcohol-Associated Liver Disease ​ ​ 58 ​ ​ — ​ ​ 58   100 % Alcohol Use Disorder ​ ​ 316 ​ ​ — ​ ​ 316   100 % Other pemvidutide expenses ​ ​ 2,540 ​ ​ 4,790 ​ ​ (2,250)   (47) % Total pemvidutide expenses ​ ​ 9,231 ​ ​ 13,527 ​ ​ (4,296) ​ (32) % HepTcell ​   — ​ ​ 1,025 ​ ​ (1,025)   100 % Non-project costs ​   6,596 ​ ​ 6,935 ​ ​ (339)   (5) % Total research and development expenses ​ $ 15,827 ​ $ 21,487 ​ $ (5,660)   (26) % ​ The decrease in research and development expenses for MASH was primarily due to ongoing enrollment for the IMPACT Phase 2b trial in MASH during the first half of 2024. The decrease in other pemvidutide expenses was primarily due to a $1.6 million decrease in manufacturing expenses. These decreases were partially offset by the increase in expense associated with the start of the AUD and ALD trials. The decrease in research and development expenses for HepTcell was due to the termination of HepTcell in March 2024. If the Staff should have any questions, or would like further information, concerning any of the responses above, please do not hesitate to contact the undersigned at (617) 699-5876 or gweaver@altimmune.com. We thank you in advance for your attention to the above. ​ Sincerely, Altimmune, Inc. /s/ Gregory Weaver ​ ​ Gregory Weaver Chief Financial Officer Cc: Joseph C. Theis, Goodwin Procter LLP ​

<DOCUMENT>
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<TEXT>
 August 8, 2025

Gregory Weaver
Chief Financial Officer
Altimmune, Inc.
910 Clopper Road, Suite 201S
Gaithersburg, MD 20878

 Re: Altimmune, Inc.
 Form 10-K for the Fiscal Year Ended December 31, 2024
 Form 10-Q for the Quarterly Period Ended March 31, 2025
 File No. 001-32587
Dear Gregory Weaver:

 We have limited our review of your filing to the financial statements
and related
disclosures and have the following comment.

 Please respond to this letter within ten business days by providing the
requested
information or advise us as soon as possible when you will respond. If you do
not believe
our comment applies to your facts and circumstances, please tell us why in your
response.

 After reviewing your response to this letter, we may have additional
comments.

Form 10-Q for the Quarterly Period Ended March 31, 2025
Management's Discussion and Analysis of Financial Condition and Results of
Operations,
page 13
Results of Operations, page 14

1. We note you have not broken out your research and development (R&D)
expenses by
 product or category, unlike in the December 31, 2024 Form 10-K and the
Forms 10-Q
 of 2024. Given R&D continues to account for most of your operating
expenses and
 the expanded indications for pemvidutide, please provide revised
disclosure to be
 included in future filings to quantify your direct R&D by product and
indication for
 each period presented. As part of your response, please provide what
this disclosure
 would have looked like had it been included in your March 31, 2025 Form
10-Q.
 In closing, we remind you that the company and its management are
responsible for
the accuracy and adequacy of their disclosures, notwithstanding any review,
comments,
action or absence of action by the staff.
 August 8, 2025
Page 2

 Please contact Jenn Do at 202-551-3743 or Vanessa Robertson at
202-551-3649 with
any questions.

 Sincerely,

 Division of Corporation
Finance
 Office of Life Sciences
</TEXT>
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CORRESP
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 Altimmune, Inc. 910 Clopper Road, Suite 201S Gaithersburg, Maryland 20878 March 11, 2025 Via EDGAR United States Securities and Exchange Commission Division of Corporation Finance Office of Life Sciences 100 F Street, N.E. Washington, D.C. 20549 ​ Re: Altimmune, Inc.: Registration Statement on Form S-3, filed February 27, 2025 (File No. 333- 285355) ​ Ladies and Gentlemen: Pursuant to Rule 461 under the Securities Act of 1933, as amended (the “ Act ”), Altimmune, Inc. (the “ Company ”) hereby requests that the effective date of the above-referenced registration statement (the “ Registration Statement ”) be accelerated to March 13, 2025, at 5:00 pm Eastern Time, or as soon thereafter as practicable, unless we or our outside counsel, Goodwin Procter LLP (“ Goodwin ”), request by telephone that such Registration Statement be declared effective at some other time. In making this acceleration request, the Company acknowledges that it is aware of its responsibilities under the Act. Once the Registration Statement is effective, please orally confirm the event with our counsel, Goodwin, by calling Justin Anslow at (212) 459-7126. We also respectfully request that a copy of the written order from the Securities and Exchange Commission verifying the effective time and date of the Registration Statement be sent to our counsel, Goodwin, Attention: Justin Anslow, by email at JAnslow@goodwinlaw.com. If you have any questions regarding this request, please contact Justin Anslow of Goodwin at (212) 459-7126. ​ Sincerely, Altimmune, Inc. /s/ Gregory Weaver ​ ​ Gregory Weaver Chief Financial Officer cc: Vipin K. Garg, Altimmune, Inc. Joseph Theis, Esq., Goodwin Procter LLP Justin Anslow, Esq., Goodwin Procter LLP ​

March 5, 2025
Vipin Garg
Chief Executive Officer
Altimmune, Inc.
910 Clopper Road, Suite 201S
Gaithersburg, MD 20878
Re:Altimmune, Inc.
Registration Statement on Form S-3
Filed February 27, 2025
File No. 333-285355
Dear Vipin Garg:
            This is to advise you that we have not reviewed and will not review your registration
statement.
            Please refer to Rules 460 and 461 regarding requests for acceleration. We remind you
that the company and its management are responsible for the accuracy and adequacy of their
disclosures, notwithstanding any review, comments, action or absence of action by the staff.
            Please contact Tyler Howes at 202-551-3370 with any questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:Joseph C. Theis, Esq.

CORRESP
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Acceleration Request

 Altimmune, Inc.

910 Clopper Road, Suite 201S

Gaithersburg, Maryland 20878

January 7, 2021

 Via EDGAR Transmission

United States Securities and Exchange Commission

 Division
of Corporation Finance

 100 F Street, N.E.

 Washington,
D.C. 20549

Re:
 Altimmune, Inc.: Registration Statement on
Form S-3, filed December 31, 2020 (File No. 333-251858)

Ladies and Gentlemen:

 Pursuant to
Rule 461 under the Securities Act of 1933, as amended (the “Act”), Altimmune, Inc. (the “Company”) hereby requests that the effective date of the above-referenced registration statement (the
“Registration Statement”) be accelerated to January 11, 2021, at 4:01 pm Eastern Time, or as soon thereafter as practicable, unless we or our outside counsel, Goodwin Procter LLP, request by telephone that such
Registration Statement be declared effective at some other time. In making this acceleration request, the Company acknowledges that it is aware of its responsibilities under the Act.

If you have any questions regarding this request, please contact Joseph Theis of Goodwin Procter LLP at
(617) 570-1928.

 Sincerely,

 Altimmune, Inc.

/s/  William Brown

 William Brown

 Chief Financial
Officer

cc:
 Vipin K. Garg, Altimmune, Inc.

 Joseph Theis, Esq., Goodwin Procter LLP

 Seo Salimi, Esq., Goodwin Procter LLP

United States securities and exchange commission logo
January 7, 2021
Vipin K. Garg
Chief Executive Officer
Altimmune, Inc.
910 Clopper Road, Suite 201S
Gaithersburg, Maryland
Re:Altimmune, Inc.
Registration Statement on Form S-3
Filed December 31, 2020
File No. 333-251858
Dear Dr. Garg:
            This is to advise you that we have not reviewed and will not review your registration
statement.
            Please refer to Rules 460 and 461 regarding requests for acceleration.  We remind you
that the company and its management are responsible for the accuracy and adequacy of their
disclosures, notwithstanding any review, comments, action or absence of action by the staff.
            Please contact Alan Campbell at 202-551-4224 with any questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:       Joseph C. Theis, Esq.

August 22, 2019
Vipin K. Garg
Chief Executive Officer
Altimmune, Inc.
910 Clopper Road, Suite 201S
Gaithersburg, Maryland, 20878
Re:Altimmune, Inc.
Preliminary Proxy Statement on Schedule 14A
Filed August 9, 2019
File No. 001-32587
Dear Dr. Garg:
            We have completed our review of your filing.  We remind you that the company and its
management are responsible for the accuracy and adequacy of their disclosures, notwithstanding
any review, comments, action or absence of action by the staff.
Sincerely,
Division of Corporation Finance
Office of Healthcare & Insurance
cc:       Joseph C. Theis, Jr. - Goodwin Procter LLP

CORRESP
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CORRESP

 August 19, 2019

VIA EDGAR AND OVERNIGHT COURIER

 U.S. Securities
and Exchange Commission

 100 F Street, N.E.

 Washington, D.C.
20549

Attn:
 Irene Paik

Re:
 Altimmune, Inc.

Preliminary Proxy Statement on Schedule 14A

Filed August 9, 2019

File No. 001-32587

Ladies and Gentlemen:

 This letter is submitted
on behalf of Altimmune, Inc. (the “Company”), to respond to comments of the staff (the “Staff”) of the Securities and Exchange Commission (the “Commission”) raised in your
letter dated August 16, 2019 with respect to the Company’s preliminary proxy statement filed with the Commission on August 9, 2019 (the “Proxy Statement”) pursuant to Section 14(a) of the Securities
Exchange Act of 1934. The Company is concurrently filing Amendment No. 1 to the Proxy Statement, which includes changes that reflect responses to the Staff’s comments.

For convenience of reference, we have set forth the Staff’s comment below, followed by our response. Capitalized terms used in this
letter without definition have the same meanings given to them in the Proxy Statement unless otherwise indicated.

 The responses provided
herein are based upon information provided to Goodwin Procter LLP by the Company. In addition to submitting this letter via EDGAR, we are sending via Federal Express four (4) copies of this letter.

Preliminary Proxy Statement on Schedule 14A

 Proposal 5, page
27

1.
 We note that your proposal to approve the issuance of common stock in connection with future milestone
payments is a result of your merger with Spitfire Pharma, Inc. Please revise your proxy statement to provide all of the information relating to Spitfire and the merger that is required by Items 11, 13 and 14 of Schedule 14A, as applicable.
Please refer to Note A of Schedule 14A.

 Response: In response to the Staff’s comment, and pursuant to
Item 11 of Schedule 14A, the Company has revised the disclosure on pages 5, 27, 28 and 29 of Amendment No. 1 to the Proxy Statement to (i) clarify the calculation of the number of its common stock to be issued upon satisfaction of the
milestones (the “Contingent Shares”), (ii) provide a

statement on preemptive rights and (iii) state the effect of the issuance of the Contingent Shares upon the rights of existing holders of the Company’s common stock. The Company
respectfully notes that the actual number of Contingent Shares is not currently determinable since the number is dependent on the Company’s future share price. Additionally, the Company respectfully notes that pursuant to Item 11(b) of Schedule
14A, because the Contingent Shares are of the same class as the Company’s currently outstanding common stock, the information called for by Item 202 of Regulation S-K is not required other than as
set forth in Item 11(b). The Company has also revised the disclosure on pages 44 and 45 of Amendment No. 1 to incorporate by reference the information set forth in Item 13(a).

The Company respectfully advises the Staff that it does not believe that Item 14 of Schedule 14A is applicable, and that the information called
for therein is not material to, and may potentially mislead, the Company’s stockholders in connection with their voting decision on Proposal 5.

Note A to Schedule 14A acknowledges that certain proposals to be acted upon by stockholders may involve the matters described by, and would
therefore require the disclosure of information pursuant to, more than one item of Schedule 14A. Note A goes on to provide an example of such a circumstance “where a solicitation of security holders is for the purpose of approving the
authorization of additional securities which are to be used to acquire another specified company, and the registrants’ security holders will not have a separate opportunity to vote upon the transaction, the solicitation to authorize the
securities is also a solicitation with respect to the acquisition.” (emphasis added)

 The Company respectfully submits to the Staff
that the instruction in Note A is inapplicable to Proposal 5 because it does not involve a solicitation seeking stockholder approval of the authorization of additional securities which are to be used to acquire another company. Rather, Proposal 5
seeks stockholder approval in accordance with Nasdaq Listing Rule 5635(a) and 5635(b) for the issuance of Contingent Shares upon the satisfaction of future milestones to the extent the issuance of Contingent Shares would exceed 20% of the
outstanding shares of the Company before the Acquisition (as defined below) or result in a change of control.

 While the Company is asking
its stockholders to approve the issuance of the Contingent Consideration, these additional shares to be issued, if ever, will not be used for the purpose of consummating the acquisition of Spitfire (the “Acquisition”) or any
other assets or company. The Company respectfully notes that the Acquisition closed on July 12, 2019 and the closing was not contingent upon, or subject to, stockholder approval of the Contingent Shares.

Under the Company’s organizational documents, Delaware law and the listing rules of Nasdaq, the Company and its board of directors had the
authority, without stockholder approval, to consummate the Acquisition and issue the upfront consideration of 1,887,250 unregistered shares of the Company’s common stock. The stockholders’ right is, instead, to vote now on whether the
Company may issue the Contingent Shares upon the achievement of the milestones. If the stockholders do not approve Proposal 5 then the

Company will settle such contingent obligation in cash as provided for in the Agreement and Plan of Merger and Reorganization relating to the Acquisition without the need for any further action
on the part of its stockholders.

 The Company respectfully submits that the information required by Item 14 of Schedule 14A is not material
to an investor. The Company respectfully refers to its letter addressed to the Office of the Chief Accountant, dated May 24, 2019, which set forth, among other items, its analysis for why providing separate stand-alone financial statements for
Spitfire would not be meaningful to investors, to which conclusion the Staff concurred. As a result of such conclusion, the acquisition of Spitfire does not require the presentation of financial information pursuant to Rule 3-05 and Article 11 of Regulation S-X, and the Company respectfully submits that the inclusion of any such financials may confuse an investor as to the significance of the
Acquisition.

 Finally, the Company respectfully submits that the inclusion of information required by Item 14 of Schedule 14A may, in fact,
be misleading to the Company’s stockholders by suggesting that the Company is asking for their vote, in part, to approve or disapprove of the Acquisition.
 Item 14(a) of Schedule 14A, “Applicability,” lists the matters for which
the subsequent Item 14(b) transaction information is to be provided. These matters are, exclusively, (1) a merger or consolidation; (2) an acquisition of securities of another person; (3) an acquisition of any other going
business or the assets of a going business; (4) a sale or other transfer of all or any substantial part of assets; or (5) a liquidation or dissolution. At the Company’s proposed stockholder meeting, no action is to be taken with
respect of any such matter. The inclusion of the information set forth in Item 14, if included in the Proxy Statement, may in fact cause confusion regarding the nature of Proposal 5 and mislead stockholders into believing that by voting against
Proposal 5 they are voting against the consummation of the Acquisition. We call your attention to the fact that the Proxy Statement already includes disclosure to the effect that the Acquisition has been fully consummated.

In light of the foregoing, the Company respectfully submits that the information required by Item 14 of Schedule 14A is inapplicable to the
decision to be made by the Company’s stockholders with respect to Proposal 5.

*            *
 *

 If you should have any questions concerning the enclosed matters, please contact the undersigned at (617) 570-1928.

 Very truly yours,

/s/ Joseph C. Theis, Jr.

 Joseph C. Theis, Jr., Esq.

 Enclosures:

cc:
 Vipin K. Garg, Ph.D., Chief Executive Officer, Altimmune, Inc.

William Brown, Chief Financial Officer, Altimmune, Inc.

Seo Salimi, Esq. Goodwin Procter LLP

August 16, 2019
Vipin K. Garg
Chief Executive Officer
Altimmune, Inc.
910 Clopper Road, Suite 201S
Gaithersburg, Maryland, 20878
Re:Altimmune, Inc.
Preliminary Proxy Statement on Schedule 14A
Filed August 9, 2019
File No. 001-32587
Dear Dr. Garg:
            We have reviewed your filing and have the following comment.
            Please respond to this comment within ten business days by providing the requested
information or advise us as soon as possible when you will respond.  If you do not believe our
comments apply to your facts and circumstances, please tell us why in your response.
            After reviewing your response to this comment, we may have additional comments.
Preliminary Proxy Statement on Schedule 14A filed August 9, 2019
Proposal 5 — Approval of the Issuance of our Common Stock in Connection with Milestone
Payments..., page 27
1.We note that your proposal to approve the issuance of common stock in connection with
future milestone payments is a result of your merger with Spitfire Pharma, Inc.  Please
revise your proxy statement to provide all of the information relating to Spitfire and the
merger that is required by Items 11, 13 and 14 of Schedule 14A, as applicable.  Please
refer to Note A of Schedule 14A.
            We remind you that the company and its management are responsible for the accuracy
and adequacy of their disclosures, notwithstanding any review, comments, action or absence of
action by the staff.

 FirstName LastNameVipin K. Garg
 Comapany NameAltimmune, Inc.
 August 16, 2019 Page 2
 FirstName LastName
Vipin K. Garg
Altimmune, Inc.
August 16, 2019
Page 2

            Please contact Irene Paik at 202-551-6553 or Joe McCann at 202-551-6262 with any
questions.
Sincerely,
Division of Corporation Finance
Office of Healthcare & Insurance
cc:       Joseph C. Theis, Jr. - Goodwin Procter LLP

April 11, 2019
Vipin Garg
Chief Executive Officer
Altimmune, Inc.
910 Clopper Road, Suite 201S
Gaithersburg, MD
Re:Altimmune, Inc.
Registration Statement on Form S-3
Filed April 4, 2019
File No. 333-230723
Dear Dr. Garg:
            This is to advise you that we have not reviewed and will not review your registration
statement.
            Please refer to Rules 460 and 461 regarding requests for acceleration.  We remind you
that the company and its management are responsible for the accuracy and adequacy of their
disclosures, notwithstanding any review, comments, action or absence of action by the staff.
            Please contact Joe McCann at 202-551-6262 with any questions.
Sincerely,
Division of Corporation Finance
Office of Healthcare & Insurance

CORRESP
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CORRESP

 [Company Letterhead]

April 11, 2019

 VIA EDGAR

 U.S. Securities and Exchange Commission

 Division
of Corporation Finance

 100 F St. Street, NE

 Washington,
D.C. 20549

Re:
 Altimmune, Inc.

 Registration Statement on Form S-3

 Filed on April 4, 2019

 File No. 333-230723

Ladies and Gentleman:

 Pursuant to Rules 460 and
461 under the Securities Act of 1933, as amended, Altimmune, Inc. (the “Registrant”) hereby requests acceleration of effectiveness of its registration statement on Form S-3 (File No. 333-230723), to 4:00 p.m., Eastern Time, on
April 11, 2019 or as soon as practicable thereafter.

 In connection with this request, the Registrant acknowledges that:

(1) should the Securities and Exchange Commission (the “Commission”) or the staff, acting pursuant to delegated authority,
declare the filing effective, it does not foreclose the Commission from taking any action with respect to the filing;

 (2) the action
of the Commission or the staff, acting pursuant to delegated authority, in declaring the filing effective, does not relieve the Registrant from its full responsibility for the adequacy and accuracy of the disclosure in the filing; and

(3) the Registrant may not assert staff comments and the declaration of effectiveness as a defense in any proceeding initiated by the
Commission or any person under the federal securities laws of the United States.

 The Company requests that it be notified of such
effectiveness by a telephone call to Will Brown at (334) 313-2319.

Very truly yours,

Altimmune, Inc.

By:

/s/ Will Brown

Name:

Will Brown

Title:

Acting Chief Financial Officer

CORRESP
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CORRESP

 [Company Letterhead]

April 11, 2019

 VIA EDGAR

 U.S. Securities and Exchange Commission

 Division
of Corporation Finance

 100 F St. Street, NE

 Washington,
D.C. 20549

Re:
 Altimmune, Inc.

Registration Statement on Form S-3

Filed on April 4, 2019

File No. 333-230723

Ladies and Gentleman:

 Pursuant to Rules 460
and 461 under the Securities Act of 1933, as amended, Altimmune, Inc. (the “Registrant”) hereby requests acceleration of effectiveness of its registration statement on Form S-3 (File No. 333-230723), to 4:00 p.m., Eastern Time, on April 12, 2019 or as soon as practicable thereafter. We hereby simultaneously withdraw our prior request for effectiveness as of April 11,
2019.

 In connection with this request, the Registrant acknowledges that:

(1) should the Securities and Exchange Commission (the “Commission”) or the staff, acting pursuant to delegated authority,
declare the filing effective, it does not foreclose the Commission from taking any action with respect to the filing;

 (2) the action
of the Commission or the staff, acting pursuant to delegated authority, in declaring the filing effective, does not relieve the Registrant from its full responsibility for the adequacy and accuracy of the disclosure in the filing; and

(3) the Registrant may not assert staff comments and the declaration of effectiveness as a defense in any proceeding initiated by the
Commission or any person under the federal securities laws of the United States.

 The Company requests that it be notified of such
effectiveness by a telephone call to Will Brown at (334) 313-2319.

 Very truly yours,

Altimmune, Inc.

By:

/s/ Will Brown

Name:

Will Brown

Title:

Acting Chief Financial Officer

CORRESP
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CORRESP

 ALTIMMUNE, INC.

910 Clopper Road, Suite 201S

Gaithersburg, Maryland 20878

 September 27,
2018

 VIA EDGAR

 United States Securities and
Exchange Commission

 Division of Corporate Finance

 100 F
Street, N.E.

 Washington, DC 20549-3628

Attention:
 Ms. Suzanne Hayes, Assistant Director

 Ms. Irene J. Paik, Attorney Adviser

Re:
 Registration Statement on Form S-1 (File No. 333-
226441)

 Ladies and Gentlemen:

Pursuant to Rule 461 promulgated under the Securities Act of 1933, as amended, the undersigned registrant (the “Company”) hereby
requests that the effective date of the above-referenced Registration Statement be accelerated so that the same may become effective at 5:00 p.m. (Washington D.C. time) on Thursday, September 27, 2018 or as soon as practicable thereafter.

 Please contact Ori Solomon of Proskauer Rose LLP, counsel to the Company, at (617) 526-9889 if
you have any questions about this letter.

 [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

Sincerely,

ALTIMMUNE, INC.

/s/ William Brown

William Brown

Acting Chief Financial Officer

cc:
 Ori Solomon, Proskauer Rose LLP

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UW Acceleration Request

 Roth Capital Partners, LLC

888 San Clemente Drive

Newport Beach, CA 92660

September 27, 2018

 Securities and Exchange Commission

 100 F Street, N.E.

 Washington, D.C. 20549

Re:
 Altimmune, Inc. (the “Company”)

 Registration Statement on Form S-1 (File No. 333-226441)

 Ladies and Gentlemen:

In connection with the above-captioned registration statement, and pursuant to Rule 461 under the Securities Act of 1933, as amended (the “Act”),
Roth Capital Partners, LLC, as the sole underwriter, hereby joins in the request of the Company that the effective date of such registration statement be accelerated to 5:00 p.m. (Eastern time) on Thursday, September 27, 2018, or as soon
thereafter as practicable.

 In making this request the undersigned acknowledges that it is aware of its obligations under the Act as they relate to the
public offering of securities pursuant to the registration statement.

[Signature Page Follows]

 Very truly yours,

ROTH CAPITAL PARTNERS, LLC,

 As the Sole Underwriter

By:

/s/ Aaron M. Gurewitz

 Name:

 Title:

 Aaron M. Gurewitz

 Head of Equity Capital
Markets

August 8, 2018
William Enright
President and Chief Executive Officer
Altimmune, Inc.
910 Clopper Road, Suite 201S
Gaithersburg, Maryland 20878
Re:Altimmune, Inc.
Registration Statement on Form S-1
Filed July 30, 2018
File No. 333-226441
Dear Mr. Enright:
            This is to advise you that we have not reviewed and will not review your registration
statement.
            Please refer to Rules 460 and 461 regarding requests for acceleration.  We remind you
that the company and its management are responsible for the accuracy and adequacy of their
disclosures, notwithstanding any review, comments, action or absence of action by the staff.
            Please contact Irene Paik at 202-551-6553 with any questions.
Sincerely,
Division of Corporation Finance
Office of Healthcare & Insurance
cc:       Stuart Bressman, Esq. - Proskauer Rose LLP

CORRESP
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April 6, 2017

VIA EDGAR

U.S. Securities and Exchange Commission

Division of Corporation Finance

100 F Street, NE

Washington, DC 20549

    Re:

        PharmAthene, Inc.

        Registration Statement on Form S-3

        File No. 333-217034

        Acceleration Request

        Requested Date: April 6,
        2017

        Requested Time: 5:00 pm Eastern Time

Ladies and Gentlemen:

Pursuant to Rule 461
under the Securities Act of 1933, as amended, PharmAthene, Inc. (the “Registrant”) hereby requests that the effective
date of the above-referenced Registration Statement on Form S-3 be accelerated so that the Registration Statement may become effective
at the “Requested Date” and “Requested Time” set forth above, or at such later time as the Registrant or
its counsel, Dentons US LLP, may orally request via telephone call to the staff of the Division of Corporation Finance of the Securities
and Exchange Commission.

Please call Jeffrey A. Baumel of Dentons
US LLP at (973) 912-7189 to confirm the effectiveness of the Registration Statement or with any questions.

    Very truly yours,

    PHARMATHENE, INC.

    /s/ Philip MacNeill

    Philip MacNeill

    Vice President, Chief Financial Officer,

Treasurer and Secretary

 cc: Jeffrey A. Baumel, Dentons US LLP

Mail Stop 4546
April 5 , 2017

John M. Gill
Chief Executive Officer
PharmAthene , Inc.
One Park Place
Annapolis , MD 21401

Re: PharmAthene , Inc.
  Registration Statement on Form S-3
Filed  March 30, 2017
  File No.  333-217034

Dear Mr. Gill:

This is to advise you that we have not  reviewed and will not review your registration
statement .

Please refer to Rules 460 and 461 regarding requests for acceleration.  We remind you
that the company and its management are responsible for the accuracy and adequacy of their
disclosures, notwithstanding any review, comments, action or absence of action by the staff.

Please  contact Ada D. Sarmento at (202) 551 -3798  with any questions.

Sincerely,

 /s/ Mary Beth Breslin for

Suzanne Hayes
Assistant Director
Office of Healthcare and Insurance

cc:  Asim Grabowski -Shaikh
 Dentons US LLP

CORRESP
1
filename1.htm

        Jeffrey A. Baumel

        Partner

        jeffrey.baumel@dentons.com

        D       +1 973 912
7189

        Dentons US LLP

        101 JFK Parkway

        Short Hills, NJ 07078-2708

        United States

        大成
        Salans FMC SNR Denton McKenna Long

        dentons.com

March 31, 2017

        VIA EDGAR

    United States Securities and Exchange Commission

Division of Corporate Finance

100 F Street, N.E.

Washington, D.C. 20549

Attention:  Suzanne Hayes, Assistant Director

 Re: PharmAthene, Inc.

Amendment No. 2 to Registration Statement on Form S-4

Filed March 31, 2017

File No. 333-215891

Dear Ms. Hayes:

At the request of our client, PharmAthene,
Inc. (the "Company"), we are responding to an oral comment of the staff (the "Staff") of the Division of Corporation
Finance of the Securities and Exchange Commission (the "Commission") relating to Amendment No. 1 ("Amendment No.
1") to the Registration Statement on Form S-4 (the “Registration Statement”) filed with the Commission on March
30, 2017. In conjunction with this letter, the Company is filing Amendment No. 2 to the Registration Statement.

In response to the Staff's comment, the Company
has provided the maximum number of shares to be issued on a fully-diluted basis on the cover page of the prospectus contained in
Amendment No. 2.

*******

If you have any questions or require any
additional information with respect to the above, please do not hesitate to contact me at (973) 912-7189.

        Securities and Exchange Commission

        March 31,
        2017

        Page 2

        大成
        Salans FMC SNR Denton McKenna Long

        dentons.com

    Sincerely,

    Dentons US LLP

    By:
    /s/ Jeffrey A. Baumel

    Jeffrey A. Baumel

 cc: John M. Gill, PharmAthene, Inc.

Ori Solomon, Proskauer Rose LLP

CORRESP
1
filename1.htm

March 31, 2017

VIA EDGAR

U.S. Securities and Exchange Commission

Division of Corporation Finance

100 F Street, NE

Washington, DC 20549

 RE: PharmAthene, Inc.

Registration Statement on Form S-4

Filed February 3, 2017

File No. 333-215891

Ladies and Gentlemen:

Pursuant to Rule 461
of the General Rules and Regulations under the Securities Act of 1933, as amended, PharmAthene, Inc. (the “Registrant”)
hereby requests that the effectiveness of the above-captioned Registration Statement (the “Registration Statement”)
be accelerated so that it will become effective as of 5:00 p.m. ET on March 31, 2017, or as soon thereafter as practicable.

Please call Jeffrey A. Baumel of Dentons
US LLP at (973) 912-7189 to confirm the effectiveness of the Registration Statement or with any questions.

    Very truly yours,

    PHARMATHENE, INC.

    /s/ Philip MacNeill

    Philip MacNeill

    Vice President, Chief Financial Officer,

Treasurer and Secretary

CORRESP
1
filename1.htm

        Jeffrey A. Baumel

        Partner

        jeffrey.baumel@dentons.com

        D       +1 973 912
7189

        Dentons US LLP

        101 JFK Parkway

        Short Hills, NJ 07078-2708

        United States

        大成
        Salans FMC SNR Denton McKenna Long

        dentons.com

March 29, 2017

        VIA EDGAR

    United States Securities and Exchange Commission

Division of Corporate Finance

100 F Street, N.E.

Washington, D.C. 20549

Attention:  Suzanne Hayes, Assistant Director

 Re: PharmAthene, Inc.

Amendment No. 1 to Registration Statement on Form S-4

Filed March 29, 2017

File No. 333-215891

Dear Ms. Hayes:

On behalf of our client, PharmAthene, Inc.
(the “Company”), set forth below are the Company's responses to the comments from the staff (the "Staff")
of the Division of Corporation Finance of the Securities and Exchange Commission (the "Commission") contained in the
Staff's letter dated March 2, 2017 (the “Comment Letter”) regarding your review of the above referenced Registration
Statement on Form S-4 (the "Registration Statement"). In connection with this letter, the Company is filing Amendment
No. 1 to the Registration Statement (“Amendment No. 1”) with the Commission, and is separately furnishing to the Staff
three courtesy copies of Amendment No. 1 marked to show changes from the Registration Statement filed on February 3, 2017.

For your convenience, the Staff's comments
have been reproduced below in their entirety, with the Company's response to each particular comment set forth immediately underneath
it. The headings and numbered paragraphs in this letter correspond to the headings and numbered paragraphs in the Comment Letter.
Any defined terms used but not otherwise defined herein have the meanings ascribed to such terms in Amendment No. 1.

Prospectus Cover Page

 1.

Please disclose the maximum
number of shares to be issued on a fully-diluted basis as of the most recent practicable date.

In response to the Staff's comment,
the Company has provided the maximum number of shares to be issued on a fully-diluted basis on the cover page of the
prospectus contained in Amendment No. 1.

        Securities and Exchange Commission

        March 29, 2017

        Page 2

        大成
        Salans FMC SNR Denton McKenna Long

        dentons.com

Opinion of the Financial Advisor to PharmAthene, page 114

 2.

We
note that Altimmune disclosed financial projections for the years ending 2016 through 2018, as well as certain forecasts and
estimates of potential cost savings, operating efficiencies and other synergies expected to result from the transaction to
Houlihan Lokey. Please revise your prospectus to disclose these projections, forecasts and estimates. Alternatively, please
tell us why such information is not material to security holders.

In response to the Staff's comment, and
following a discussion with the Staff, the Company has submitted under separate cover a letter via EDGAR on March 16, 2017 (the
"March 16th Letter"), which contained the Company's proposal to revise the disclosure in the Registration
Statement to disclose the information provided to Houlihan Lokey. Amendment No. 1 amends the Registration Statement to include
the disclosure as proposed in the March 16th Letter.

Where you can find additional information,
page 273

 3.

Please update this section
to incorporate by reference your Current Reports on Form 8-K filed on February 19, 2016 and February 1, 2017. For guidance, please
see Item 11(a)(2) of Form S-4.

In response to the Staff's comment, the Company
has updated the "Where You Can Find Additional Information" section of Amendment No. 1 on page 269 to incorporate
by reference the Company's Current Report on Form 8-K filed with the Commission on February 1, 2017. In addition, the Company has
incorporated by reference into the Registration Statement the Company’s Current Reports on Form 8-K filed with the Commission
on March 14, 2017 and March 29, 2017.

The Company respectfully advises the Staff
that Amendment No. 1 does not incorporate by reference the Company's Current Report on Form 8-K filed on February 19, 2016. Pursuant
to "Item 11. Incorporation of Certain Information by Reference" of Form S-4, the Company is required to incorporate by
reference all reports filed pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended, since the end
of the fiscal year covered by the annual report incorporated by reference in the Registration Statement. Because Amendment No.
1 amends the Registration Statement to incorporate by reference the Company's Annual Report on Form 10-K for the fiscal year ended
December 31, 2016, the Company is no longer required to incorporate by reference its Current Report on Form 8-K filed with the
Commission on February 19, 2016.

Exhibit 23.1

 4.

We note that the consent of the independent registered public accounting firm is not signed by your auditor.
Please file a signed consent.

In response to the Staff's comment, the
Company has filed a signed consent of the independent registered public accounting firm as Exhibit 23.1 to Amendment No. 1.

*******

If you have any questions or require any
additional information with respect to the above, please do not hesitate to contact me at (973) 912-7189.

        Securities and Exchange Commission

        March 29,
        2017

        Page 3

        大成
        Salans FMC SNR Denton McKenna Long

        dentons.com

    Sincerely,

    Dentons US LLP

    By:
    /s/ Jeffrey A. Baumel

    Jeffrey A. Baumel

 cc: John M. Gill, PharmAthene, Inc.

Ori Solomon, Proskauer Rose LLP

CORRESP
1
filename1.htm

        Jeffrey A. Baumel

        Partner

        jeffrey.baumel@dentons.com

        D       +1 973 912
7189

        Dentons US LLP

        101 JFK Parkway

        Short Hills, NJ 07078-2708

        United States

        大成
        Salans FMC SNR Denton McKenna Long

        dentons.com

March 16, 2017

        VIA EDGAR

    United States Securities and Exchange Commission

Division of Corporate Finance

100 F Street, N.E.

Washington, D.C. 20549

Attention:  Suzanne Hayes, Assistant Director

 Re: PharmAthene, Inc.

Registration Statement on Form S-4

Filed February 3, 2017

File No. 333-215891

Dear Ms. Hayes:

On behalf of our client, PharmAthene, Inc.
(the “Company”), we submit this letter in response to the March 2, 2017 comment letter (the “Comment Letter”)
of the staff (the “Staff”) of the Securities and Exchange Commission (the “Commission”) relating to the
above-referenced Registration Statement on Form S-4 (the “Registration Statement”).

As previously discussed with the Staff,
we are submitting this letter via EDGAR in response to comment number 2 from the Comment Letter (“Comment 2”). For
your convenience, we have set forth below in bold Comment 2, including the caption used in the Comment Letter. Immediately following
is the Company’s response to Comment 2, which includes disclosure that the Company proposes to include in Amendment No. 1
to the Registration Statement. The Company intends to file Amendment No. 1 to the Registration Statement and provide a separate
response letter responding to the Staff’s other comments in the Comment Letter. Defined terms used but not otherwise defined
herein have the meanings ascribed to such terms in the Registration Statement.

Opinion of the Financial Advisor to PharmAthene, page 114

 2. We note that Altimmune disclosed financial projections for the years ending 2016 through 2018, as well as certain forecasts
and estimates of potential cost savings, operating efficiencies and other synergies expected to result from the transaction to
Houlihan Lokey. Please revise your prospectus to disclose these projections, forecasts and estimates. Alternatively, please tell
us why such information is not material to security holders.

In response to the Staff's comment, the
Company proposes to revise the disclosure appearing in the "Background of the Transaction" section of the Registration
Statement to add the following:

        Securities and Exchange Commission

        March 16, 2017

        Page 2

        大成
        Salans FMC SNR Denton McKenna Long

        dentons.com

"Certain Financial Forecasts

PharmAthene and Altimmune management do
not, as a matter of course, generally prepare or make available to the public financial projections due to, among other reasons,
the inherent uncertainty, unpredictability and subjectivity of the underlying assumptions and estimates. However, in connection
with the Mergers, at the request of HL, management of both PharmAthene and Altimmune provided to HL certain financial projections
through the year ended December 31, 2018 and PharmAthene management provided to HL certain forecasts and estimates of potential
cost savings, operating efficiencies and other synergies expected to result from the Mergers, which are included in the general
and administrative expenses and research and development expenses noted below, as well as projected contract revenue, related expenses
and overhead. This unaudited prospective financial information ("prospective financial information") was based on the
respective management’s projection of its company's future financial performance as of the date prepared, were prepared to
assist HL with its financial analysis, and were not prepared with a view toward public disclosure or compliance with published
guidelines of the SEC regarding forward-looking information or the guidelines established by the American Institute of Certified
Public Accountants for preparation and presentation of financial forecasts or GAAP. Neither PharmAthene's nor Altimmune's independent
registered public accounting firm nor any other independent accountants have compiled, examined or performed any procedures with
respect to this prospective financial information, nor have they expressed any opinion or given any form of assurance on the prospective
financial information or the achievability of any of the numbers included therein. The prospective financial information includes
a non-GAAP financial measure. Non-GAAP financial measures should not be considered in isolation from, or as a substitute for, financial
information presented in compliance with GAAP, and non-GAAP financial measures included in the prospective financial information
may not be comparable to similarly titled amounts used by other companies.

The prospective financial information in
this proxy statement/prospectus/consent solicitation are being provided solely to give the stockholders of PharmAthene and Altimmune
access to certain information that was made available to HL. In compiling the prospective financial information, management of
PharmAthene and Altimmune took into account historical performance, combined with estimates regarding revenues, general and administrative
expenses, and research and development expenses. Although the prospective financial information is presented with numerical specificity,
they reflect numerous assumptions and estimates as to future events made by management of PharmAthene and Altimmune that the respective
management believed were reasonable at the time the projections were prepared. However, this information is not fact, and should
not be relied upon as being indicative of actual future results and the delivery of the prospective financial information should
not be regarded as an indication that PharmAthene, Altimmune or any of their respective affiliates, officers, directors, partners,
advisors or other representatives considered, or now consider, those projections to be necessarily predictive of actual future
results. In addition, the prospective financial information provided herein does not necessarily reflect certain changes to the
assumptions and estimates relied upon by management of PharmAthene and Altimmune since the information was provided to HL. Furthermore,
since the prospective financial information covers multiple years, such information by its nature becomes less predictive with
each successive year.

        Securities and Exchange Commission

        March 16, 2017

        Page 3

        大成
        Salans FMC SNR Denton McKenna Long

        dentons.com

There are various risks associated with
PharmAthene, Altimmune and the Mergers, including the factors described under the section of this proxy statement/prospectus/consent
solicitation entitled “Risk Factors,” as well as the documents that PharmAthene has filed with the SEC that are incorporated
by reference in this proxy statement/prospectus/consent solicitation, which are difficult to predict and beyond the control of
management of PharmAthene and Altimmune, and which may cause the projections or the underlying assumptions not to be reflective
of actual future results. The prospective financial information does not take into account any circumstances or events occurring
after the date that they were prepared and, accordingly, do not give effect to any changes to operations or strategy that may be
implemented or that were not anticipated after the time the projections were prepared. As a result, the projections may not be
realized, and actual results may be materially different than those contained in the prospective financial information. Shareholders
are cautioned not to place undue reliance on the information presented below, and should refer to the section “Altimmune’s
Management’s Discussion and Analysis of Financial Condition and Results of Operations – Liquidity” included in
this proxy statement/prospectus/consent solicitation, and the corresponding sections in the documents that PharmAthene has filed
with the SEC that are incorporated by reference into this proxy/statement/prospectus/consent solicitation, for information with
respect to the cash obligations and the ability to fund the operations of each company. Neither PharmAthene, Altimmune nor any
of their respective affiliates, advisors, officers, directors or representatives can give any assurance that actual results will
not differ from the prospective financial information, and neither PharmAthene, Altimmune nor any of their respective affiliates,
advisors, officers, directors or representatives undertakes any obligation to update, or publicly disclose any update to, this
prospective financial information to reflect circumstances or events, including unanticipated events, that may have occurred or
that may occur after the preparation of these projections, even in the event that any or all of the assumptions underlying the
prospective financial information are shown to be in error or change. Neither PharmAthene nor Altimmune intend to make available
publicly any update or other revision to the prospective financial information, except as otherwise required by law.

Subject to the foregoing qualifications,
PharmAthene and Altimmune provided HL with the following prospective financial information: (1) estimated annual revenue for the
Combined Company of approximately $12.0 million and $24.0 million in the years ending December 31, 2017 and 2018, respectively,
comprised of: (i) approximately $5.0 million during 2017 and $16.0 million during 2018 projected to be received by Altimmune under
its 2016 agreement with BARDA (approximately $7.0 million of which is subject to the exercise of options by BARDA); (ii) approximately
$5.1 million in 2017 and $5.7 million in 2018 projected to be received by PharmAthene under its 2014 agreement with NIAID (of which
$2.3 million in 2017 and the entirety in 2018 is subject to the exercise of an option by NIAID); and (iii) approximately $1.9 million
in 2017 and $2.3 million in 2018 projected to be received by Altimmune, comprised of anticipated research and development tax credits
and VAT refunds in the United Kingdom which are directly related to anticipated expenditures for projects relating to HepTcell,
(2) estimated research and development expenses of the Combined Company of approximately $20.9 million and $37.0 million in 2017
and 2018, respectively, (3) estimated general and administrative expenses for the Combined Company of approximately $5.1 million
and $5.2 million in 2017 and 2018, respectively, (4) estimated negative adjusted EBITDA of the Combined Company of approximately
$14.0 million and $18.2 million in 2017 and 2018, respectively; and (5) estimated cash balances of $3.3 million at December 31,
2017, negative $0.6 million at March 31, 2018 and negative $9.9 million at December 31, 2018. As used in the prospective financial
information, adjusted EBITDA includes interest and excludes depreciation and stock compensation. Shareholders should note that
these estimated cash balances were since updated and Altimmune currently believes that the net proceeds from the Altimmune Financing
Agreement and its other funding arrangements, its existing cash, and, to the extent the mergers are completed, the existing cash
of PharmAthene, will be sufficient to fund its projected operating requirements through at least the first quarter of 2018. See
“Altimmune’s Management’s Discussion and Analysis of Financial Condition and Results of Operations – Liquidity”
included in this proxy statement/prospectus/consent solicitation, and the corresponding sections in the documents that PharmAthene
has filed with the SEC that are incorporated by reference into this proxy/statement/prospectus/consent solicitation, for information
with respect to the cash obligations and the ability to fund the operations of each company."

*******

        Securities and Exchange Commission

        March 16, 2017

        Page 4

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        Salans FMC SNR Denton McKenna Long

        dentons.com

If you have any questions or require any
additional information with respect to the above, please do not hesitate to contact me at (973) 912-7189.

    Sincerely,

    Dentons US LLP

    By:
    /s/ Jeffrey A. Baumel

    Jeffrey A. Baumel

 cc: John M. Gill

Ori Solomon

Mail Stop 4546

 March 2, 2017

John M. Gill
Chief Executive Officer
PharmAthene, Inc.
One Park Place
Suite 450
Annapolis, MD 21401

Re: PharmAthene, Inc.
  Registration Statement on Form S -4
Filed February 3, 2017
  File No. 333 -215891

Dear Mr. Gill:

We have limited our review of your registration statement to those issues we have
addressed in our comments.  In some of our comments, we may ask you to provide us with
information so we may better understand your disclosure.

Please respond to this letter by amending your registration statement and providing the
requested information.   If you do not believe our comments apply to your facts and
circumstances or do not believe an amendme nt is appropriate, please tell us why in your
response.

After reviewing any amendment to your registration statement and the information you
provide in response to these comments, we may have additional comments.

Prospectus Cover Page

1. Please disclos e the maximum number of shares to be issued on a fully -diluted basis as of
the most recent practicable date.

Opinion of the Financial Advisor to PharmAthene, page 114

2. We note that Altimmune disclosed financial projections for the years ending 2016
through 2018, as well as certain forecasts and estimates of potential cost savings,
operating efficiencies and other synergies expected to result from the transaction to
Houli han Lokey.  Please revise your prospectus to disclose these projections, forecasts

John M. Gill
PharmAthene, Inc.
March 2, 2017
Page 2

 and estimates. Alternatively, please tell us why such information is not material to
security holders.

Where you can find additional information, page 273

3. Please update this section to incorporate by reference your Current Reports on Form 8 -K
filed on February 19, 2016 and February 1, 2017. For guidance, please see Item 11(a)(2)
of Form S -4.

Exhibit 23.1

4. We note that the consent of the independent registered public acco unting firm is not
signed by your auditor. Please file a signed consent.

We remind you that the company and its management are responsible for the accuracy
and adequacy of their disclosures, notwithstanding any review, comments, action or absence of
action by the staff.

Refer to Rules 460 and 461 regarding requests for acceleration.  Please allow adequate
time for us to review any amendment prior to the requested effective date of the registration
statement.

 Please contact Jeffrey Gabor at (202 ) 551 -2544 or Mary Beth Breslin at (202) 551 -3625
with any questions.

Sincerely,

 /s/ Mary Beth  Breslin for

Suzanne Hayes
Assistant Director
Office of Healthcare and Insurance

cc: Jeffrey A. Baumel, Esq.
 Dentons US LLP

CORRESP
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PHARMATHENE, INC.

One Park Place, Suite 450

Annapolis, MD 21401

October 29,
2013

United States Securities and Exchange Commission

Division of Corporate Finance

100 F. Street, N.E.

Washington, D.C. 20549

    Re:
    PharmAthene, Inc. (the "Company")

    Registration Statement on Form S-4, as amended

    File No. 333-191055

    Request for Acceleration

Ladies and Gentlemen:

Pursuant to Rule 461(a)
under the Securities Act of 1933, as amended, the Company respectfully requests acceleration of the effective date of its Registration
Statement on Form S-4, as amended (File No. 333-191055) (the "Registration Statement"), so that the same will be declared
effective on Tuesday, October 29, 2013 at 4:30 p.m. Washington D.C. time, or as soon thereafter as is practicable.

The Company hereby acknowledges that:

 · should the Securities and Exchange Commission (the “Commission”)
or the staff, acting pursuant to delegated authority, declare the Registration Statement effective, it does not foreclose the Commission
from taking any action with respect to the Registration Statement;

 · the action of the Commission or the staff, acting pursuant to delegated
authority, in declaring the Registration Statement effective, does not relieve the Company from its full responsibility for the
adequacy and accuracy of the disclosure in the Registration Statement; and

 · the Company may not assert staff comments and the declaration of effectiveness
as a defense in any proceeding initiated by the Commission or any person under the federal securities laws of the United States.

Please contact our
counsel, Jeffrey A. Baumel (973-912-7189) or Rani Doyle (212-398-8467) of Dentons US LLP, with respect to any comments or questions
relating to the Registration Statement or this request for acceleration of effectiveness.

    Very truly yours,

    PHARMATHENE, INC.

    By:
    /s/ Eric I. Richman

    Eric I. Richman

    Chief Executive Officer

    - 2 -

CORRESP
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VIA EDGAR

October 22, 2013

Jeffrey P. Riedler

Assistant Director

Division of Corporation Finance

United States Securities and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549

 Re: PharmAthene, Inc.

Registration Statement on Form S-4

Filed September 9, 2013

File No. 333-191055

Dear Mr. Riedler:

PharmAthene, Inc. (the "Company") submits this letter
in response to a comment letter dated October 16, 2013 received from the Staff of the Securities and Exchange Commission (the “Commission”)
with respect to the Registration Statement on Form S-4 (the “Registration Statement”) filed by the Company on September
9, 2013.

In order to facilitate your review of our responses, the numbered
paragraph below corresponds and responds to the Staff’s comment, which is restated below in bold text.

Form S-4

Risk Factors, page 35

1.	We note your response to our prior comment 1 and proposed
risk factor disclosure. Please also include in your risk factor disclosure in the pre-merger amount of each company's net operating
loss and tax credit carryforwards. In addition, to the extent practicable, please quantify the likely effect of the merger transaction
on the pre-merger carryforwards arising from the application of Sections 382 and 384.

The Company undertakes to disclose in the
risk factor the pre-merger amounts of each of its and Theraclone's net operating loss and tax credit carryforwards, as noted below.
The Company respectfully advises that it has not undertaken a definitive analysis necessary to quantify the effect of the merger
on the pre-merger carryforwards with requisite precision. To address
the request, however, the Company proposes to add disclosure, indicated by underlined text, to the risk factor that it has undertaken
to add in response to the Staff's first comment in its previous comment letter to the Company as follows:

The combined company’s ability to utilize PharmAthene’s
or Theraclone’s net operating loss and tax credit carryforwards in the future may be subject to substantial limitations and
may be further limited as a result of the merger.

Under Section 382 of the Code, if
a corporation undergoes an “ownership change” (generally defined as a greater than 50 percent change (by value)
in its equity ownership over a three-year period), the corporation’s ability to use its pre-change net operating
loss carryforwards and other pre-change tax attributes to offset its post-change income may be limited. Further, if the
historic business of PharmAthene or Theraclone is not treated as being continued by the combined entity for the two-year
period beginning on the date of the merger (referred to as the “continuity of business requirement”),
the pre-transaction net operating loss carryforward deductions of PharmAthene or Theraclone (as the case may be) may
become substantially reduced or unavailable for use by the combined company. Prior to the merger, PharmAthene may have
undergone an “ownership change”, and it is expected that the merger will likely result in an “ownership
change” of PharmAthene. In addition, it is expected that the merger will result in an “ownership change” of
Theraclone. A corporation that experiences an ownership change will generally be subject to an annual limitation on its
use of pre-ownership change net operating loss carryforwards (and certain other pre-change tax attributes) equal to, in
general, the product of the long-term tax-exempt rate (as published by the IRS for the month in which the ownership change
occurs, which rate is 3.50% for October 2013) and the value of the corporation's outstanding stock immediately before the
ownership change (subject to certain adjustments), increased by certain built-in gains held by the corporation at the time of
the ownership change that are recognized in the five-year period after the ownership period. Accordingly, the combined
company’s ability to utilize PharmAthene’s and Theraclone’s pre-merger net operating loss and tax credit
carryforwards, which for PharmAthene was, as of December 31, 2012, approximately $134.3 million and for
Theraclone was, as of December 31, 2012,  approximately $41.2 million, may be substantially limited. PharmAthene’s
U.S. federal net operating loss carryforwards of approximately $134.3 million will begin to expire in various years beginning
in 2021. Theraclone’s U.S. federal net operating loss carryforwards of approximately $41.2 million will begin to expire
in various years beginning in 2024. These limitations,
in turn, could result in increased future tax payments for the combined company, which could have a material adverse effect
on the business, financial condition or results of operations of the combined company.

Under Section 384 of the Code, available
net operating loss carryovers of PharmAthene or Theraclone may not be available to offset certain gains arising after the merger
from assets held by the other corporation at the effective time of the merger. This limitation will apply to the extent that the
gain is attributable to an unrealized built-in-gain in the assets of PharmAthene or Theraclone existing at the effective time of
the merger. To the extent that any such gains are recognized in the five-year period after the merger upon the disposition of any
such assets, the net operating loss carryovers of the other corporation will not be available to offset such gains (but the net
operating loss carryovers of the corporation that owned such assets will not be limited by Section 384 of the Code although they
may be subject to other limitations under Section 382 of the Code as described above).

*     	*     	*

The Company acknowledges that:

 • should the Commission or the Staff, acting pursuant to
delegated authority, declare the filing effective, it does not foreclose the Commission from taking any action with respect to
the filing;

 • the action of the Commission of the Staff, acting pursuant
to delegated authority, in declaring the filing effective, does not relieve the Company from its full responsibility for the adequacy
and accuracy of the disclosure in the filing; and

•	   the Company may not assert Staff comments and the
declaration of effectiveness as a defense in any proceedings initiated by the Commission or any person under the federal securities
laws of the United States.

If you have any questions, or if we may be of any assistance,
please do not hesitate to contact the undersigned at (410) 269-2600 or our counsel, Jeffrey Baumel of Dentons US LLP, at (973)
912-7189.

Sincerely,

/s/ Eric Richman

Eric Richman

Chief Executive Officer

cc: Jeffrey Baumel

October 1 6, 2013

Via E -mail
Eric Richman
Chief Executive Officer
PharmAthene, Inc.
One Park Place, Suite 450
Annapolis, MD 21401

Re: PharmAthene, Inc.
  Registration Statement on Form S-4
Filed  September 9, 2013
  File No.  333-191055

Dear Mr. Richman :

We have reviewed your response letter dated October 11, 2013, and have the following
comment.

Please respond to this letter by amending your registration statement and providing the
requested information .  Where you do not believe our comment applies to your facts and
circumstances or do not believe an amendment is appropriate, please tell us why in your
response.

After revi ewing any amendment to your registration statement and the information you
provide in response to this comment , we may have  additional comments.

Risk Factors , page 35

1. We note your response to our prior comment 1 and proposed risk disclosure. Please als o
include in your risk disclosure the pre -merger amount of each company’s net operating
loss and tax credit carryforwards.  In addition, to the extent practicable, please quantify
the likely effect of the merger transaction on the pre -merger carryforwards arising from
the application of Sections 382 and 384.

We urge all persons who are responsible for the accuracy and adequacy of the disclosure
in the filing to be certain that the filing includes the information the Securities Act of 193 3 and
all applicable Securities  Act rules require.   Since the company and its management are in
possession of all facts relating to a company’s disclosure, they are responsible for the accuracy
and adequacy of the disclosures they have made.

Mr. Eric Richman
PharmAthene, Inc.
October 1 6, 2013
Page 2

 Notwithstand ing our comments, in the event you request acceleration of the effective date
of the pending registration statement please provide a written statement from the company
acknowledging that:

 should the Commission or the staff, acting pursuant to delegated au thority, declare the
filing effective, it does not foreclose the Commission from taking any action with respect
to the filing;

 the action of the Commission or the staff, acting pursuant to delegated authority, in
declaring the filing effective, does not relieve the company from its full responsibility for
the adequacy and accuracy of the disclosure in the filing; and

 the company  may not assert staff comments and the declaration of effectiveness as a
defense in any proceeding initiated by the Commission or any person under the federal
securities laws of the United States.

Please refer to Rules 460 and 461 regarding requests for  acceleration .  We will consider a
written request for acceleration of the effective date of the registration statement as confirmation
of the fact that those requesting acceleration are aware of their respective responsibilities under
the Securities Act of 1933 and the Securities Exchange Act of 1934 as they relate to the proposed
public offering of the securities specified in the above registration statement.  Please allow
adequate time  for us to review any amendment prior to the requested effective date of  the
registration statement.

Please contact Matthew Jones  at (202) 551 -3786, Dan Greenspan at (202) 551 -3623, or
me at (202) 551 -3715  with any other questions.

Sincerely,

 /s/ Daniel Greenspan for

Jeffrey P. Riedler
Assistant Director

cc:  Jeffrey Baumel
 Dentons US L LP
 1221 Avenue of the Americas
 New York, New York 10020 -1089

CORRESP
1
filename1.htm

PharmAthene, Inc.

One Park Place, Suite 450

Annapolis, MD 21401

VIA EDGAR

October 10, 2013

Jeffrey P. Riedler

Assistant Director

Division of Corporation Finance

United States Securities and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549

 Re: PharmAthene, Inc.

Registration Statement on Form S-4

Filed September 9, 2013

File No. 333-191055

Dear Mr. Riedler:

PharmAthene, Inc. (the "Company")
submits this letter in response to a comment letter dated October 1, 2013 received from the Staff of the Securities and Exchange
Commission (the “Commission”) with respect to the Registration Statement on Form S-4 (the “Registration Statement”)
filed by the Company on September 9, 2013.

In order to facilitate your review of our
responses, the numbered paragraphs set forth below correspond to the Staff’s comments, which are restated below
in bold text.

Form S-4

Risk Factors, page 35

 1. We note your discussion on pages F-24 and F-62 that
each of PharmAthene's and Theraclone's net operating loss carry forwards may be limited due to underlying ownership of the respective
company's common stock. Please include a new risk factor that addresses the circumstances under which the completion of your proposed
merger could result in an "ownership change" for purposes of Section 382 of the Internal Revenue Code for each of PharmAthene
or Theraclone and the impact on existing U.S. federal net operating loss carry forwards and other tax credit carry forwards.

To address the Staff's comment, the Company intends to add the following disclosure as a new risk factor
on page 38 of the Registration Statement, under the sub-caption “Risks Related to the Proposed Merger.”

The combined company’s
ability to utilize PharmAthene’s or Theraclone’s net operating loss and tax credit carryforwards in the future may
be subject to substantial limitations and may be further limited as a result of the merger.

Under Section 382 of the Code, if
a corporation undergoes an “ownership change” (generally defined as a greater than 50 percent change (by value) in
its equity ownership over a three-year period), the corporation’s ability to use its pre-change net operating loss carryforwards
and other pre-change tax attributes to offset its post-change income may be limited. Further, if the historic business of PharmAthene
or Theraclone is not treated as being continued by the combined entity for the two-year period beginning on the date of the merger
(referred to as the “continuity of business requirement”), the pre-transaction net operating loss carryforward deductions
of PharmAthene or Theraclone (as the case may be) may become substantially reduced or unavailable for use by the combined company.
Prior to the merger, PharmAthene may have undergone an “ownership change”, and it is expected that the merger will
likely result in an “ownership change” of PharmAthene. In addition, it is expected that the merger will result in
an “ownership change” of Theraclone. Accordingly, the combined company’s ability to utilize PharmAthene’s
and Theraclone’s net operating loss and tax credit carryforwards may be substantially limited. These limitations, in turn,
could result in increased future tax payments for the combined company, which could have a material adverse effect on the business,
financial condition or results of operations of the combined company.

Under Section 384 of the Code, available net operating loss
carryovers of PharmAthene or Theraclone may not be available to offset certain gains arising after the merger from assets held
by the other corporation at the effective time of the merger. This limitation will apply to the extent that the gain is attributable
to an unrealized built-in-gain in the assets of PharmAthene or Theraclone existing at the effective time of the merger. To the
extent that any such gains are recognized in the five-year period after the merger upon the disposition of any such assets, the
net operating loss carryovers of the other corporation will not be available to offset such gains (but the net operating loss
carryovers of the corporation that owned such assets will not be limited by Section 384 of the Code although they may be subject
to other limitations under Section 382 of the Code as described above).

"All of PharmAthene's immediately
foreseeable future revenues are contingent upon grants and contracts from the U.S. government…," page 46

 2. We note your disclosure on page 47 that future funding
levels for two of PharmAthene's key government customers, BARDA and DoD, are uncertain and may be subject to budget cuts as the
U.S. Congress and the President look to reduce the nation's budget deficit. At the same time, however, we note that the Pandemic
and All-Hazards Preparedness Reauthorization Act of 2013 authorized appropriation of $2.8 billion for the period of fiscal years
2014 to 2018, a substantial portion of which funding is allocated to BARDA. Please expand your disclosure to state how the Pandemic
and All-Hazards Preparedness Reauthorization Act of 2013 relates to BARDA funding and future revenues that may be received by
PharmAthene from BARDA, as well as the impact of the sequestration on the federal appropriations provided to BARDA under the Reauthorization
Act.

In response to the
Staff's comment, the Company proposes to revise the risk factor, by revising the seventh full paragraph of the risk factor,
copied below in italicized text, as follows: (i) to delete the text shown as stricken text, as the U.S. government is now in
a new fiscal year; and (ii) to add disclosure shown in underlined text to address the Pandemic and All-Hazards
Preparedness Reauthorization Act of 2013 in relation to BARDA.

As of December 31, 2012, of the
total $5.6 billion allotted under Project BioShield in 2004, over $2.6 billion in procurement contracts had been awarded and approximately
$2.3 billion had been transferred out of the Project BioShield Special Reserve Fund, or SRF, for non-procurement related activities.
Remaining funds in the SRF were approximately $500 million as of December 31, 2012. It is expected that BARDA, which administers
the SRF, obligated these remaining funds as of the end of the fiscal year 2013 (i.e. September 30, 2013).
Sequestration was applied to fiscal year 2013 funding only. As BARDA was funded through a transfer of the SRF advanced
appropriation, and not fiscal year 2013 funds, its funding was not impacted. Currently,
the government is operating under a continuing resolution at the fiscal year 2012 level. As $415 million was the level of annual
funding for BARDA operations in fiscal year 2012, that amount is being transferred from the SRF to cover fiscal year 2013 operating
expenses, and thus will not be available for product purchases for the U.S. Strategic National Stockpile. The
Pandemic and All Hazards Preparedness Act Reauthorization ("PAHPA") signed into law in March 2013 authorized $2.8 billion
in funding for the SRF for fiscal years 2014-2018. These funds are for the procurement of medical countermeasures. PAHPA also authorized
$415 million in funding to BARDA for advanced development activities. However, actual funding for BARDA is dependent on annual
congressional appropriations. Currently, Congress has not passed appropriation legislation for fiscal year 2014 and, until Congress
reaches an agreement, it is premature to predict future funding to BARDA. Until Congress reaches an agreement on the budget for
fiscal year 2014, the amount and nature of future federal budgets spending will be uncertain. Potential reductions in funding could
severely limit PharmAthene’s ability to maintain, renew or enter into new contracts with respect to its business generally
and therefore materially adversely impact PharmAthene’s business.

    -2-

Opinion of Leerink Swann, page
94

 3. We note your description of the analysis performed
by Leerink Swann in rendering its fairness opinion, which included an estimate of future revenues that PharmAthene may derive
from its pending litigation with SIGA Technologies. We further note that Leerink assumed that such future revenues will be equal
to the damages awarded to PharmAthene by the Delaware Chancery Court in its judgment dated May 31, 2012. Please expand your description
to disclose:

 · the dollar amount of estimated damages attributed to this pending
litigation for purposes of Leerink's analysis and its valuation of PharmAthene; and

 · the methodology used to derive the estimate of damages including,
if applicable, the value attributed to the net profits from sales of SIGA's ArestvyrTM

To address the Staff's comment, the Company proposes to expand the disclosure in the Registration Statement under the
                                                      sub-caption "Illustrative Sum of the Parts Analysis" on page 98, copied below in italicized text, to add the
                                                      disclosure shown in underlined text and to delete the disclosure shown as stricken text.

Leerink performed an
illustrative sum of the parts analysis on PharmAthene consisting of (i) a discounted cash flow analysis of
PharmAthene’s existing products using the financial forecasts for PharmAthene provided by management of PharmAthene,
calculated based on the forecasted free cash flows of each product from 2013 through 2021, discounted to present value using
a discount rate of 15% and applying a range of probabilities of success to such forecasts, (ii) an estimate a
discounted cash flow analysis  of the future cash flows to revenues PharmAthene which may result
from the subject matter of its pending litigation with SIGA Technologies, Inc., and which aggregate,
undiscounted cash flows Leerink assumed would calculated to be approximately $74.2 million, an
amount determined assuming the cash flows would be equal to the damages awarded by the Delaware Chancery Court in its
judgment dated May 31, 2012 (which was subsequently remanded by the Delaware Supreme Court on May 24, 2013 for
reconsideration) then discounted to present value using a discount rate of 15% and applying a 90% probability of success
to such forecasts, with Leerink also (a) assuming that SIGA would not make any further sales of ArestvyrTM
following completion of delivery of product under its current supply contract with the U.S. government and (b) applying the
post-judgment positions taken by SIGA as to the allocation of costs to ArestvyrTM and timing of sales (positions
PharmAthene disputes); and (iii) adding to the sum of the amounts derived from the analyses in (i) and (ii) above the net
cash of PharmAthene. The following table presents the results of this analysis:

    Illustrative Equity Value / Equity Value per share of

    PharmAthene Common Stock
     $89mm / $1.72

*    	*    	*

    -3-

The Company acknowledges that:

 · should the Commission or the Staff, acting pursuant to delegated authority,
declare the filing effective, it does not foreclose the Commission from taking any action with respect to the filing;

 · the action of the Commission of the Staff, acting pursuant to delegated
authority, in declaring the filing effective, does not relieve the Company from its full responsibility for the adequacy and accuracy
of the disclosure in the filing; and

 · the Company may not assert Staff comments and the declaration of effectiveness
as a defense in any proceedings initiated by the Commission or any person under the federal securities laws of the United States.

If you have any questions, or if we may be
of any assistance, please do not hesitate to contact the undersigned at (410) 269-2600 or our counsel, Jeffrey Baumel of Dentons
US LLP, at (973) 912-7189.

Sincerely,

/s/ Eric Richman

Eric Richman

Chief Executive Officer

cc: Jeffrey Baumel

    -4-

October 1, 2013

Via E -mail
Eric Richman
Chief Executive Officer
PharmAthene, Inc.
One Park Place, Suite 450
Annapolis, MD 21401

Re: PharmAthene, Inc.
  Registration Statement on Form S-4
Filed  September 9, 2013
  File No.  333-191055

Dear Mr. Richman :

We have limited our review of your registration statement to those issues we have
addressed in our comments.  In  some of our comments, we may ask you to provide us with
information so we may better understand your disclosure.

Please respond to this letter by amending your registration statement and providing the
requested information .  Where you do not believe our comments apply to your facts and
circumstances or do not believe an amendment is appropriate, please tell us why in your
response.

After reviewing any amendment to your registration statement and the information you
provide in response to these  comments , we may have  additional comments.

Risk Factors , page 35

1. We note your discussion on  pages  F-24 and F -62 that each of PharmAthene ’s and
Theraclone ’s  net operating loss carry forwards may be limited due to underlying
ownership of the respective company’s common stock. Please includ e a new risk factor
that addresses  the circumstances under which the completion of your proposed merger
could result in an “ownership change” for purposes of Section 382 of the Internal
Revenue Code for each of PharmA thene or Theraclone  and the impact on existing  U.S.
federal net operating loss carry forwards and other tax credit carry forwards.

Mr. Eric Richman
PharmAthene, Inc.
October 1, 2013
Page 2

 “All of PharmAthene’s immediately foreseeable future revenues are contingent upon grants and
contracts from the U.S.  government …,” page 46

2. We note your disclosure on page 47 that future funding levels for two of PharmAthene’s
key government customers, BARDA and DoD, are uncertain and may be subject to
budget cuts as the U.S.  Congress and the President look to reduce the nation’s budget
deficit.   At the same time, however , we note that the Pandemic and All -Hazards
Preparedn ess Reauthorization Act of 2013  authorized appropriations of $2.8 billion for
the period of f iscal years 2014 to 2018 , a substant ial portion of which funding is allocated
to BARDA. Please expand y our disclosure to state how the Pandemic and All -Hazards
Preparedn ess Reauthorization Act of 2013  relates to  BARDA funding and  future
revenues that may be received  by Phar mAthene from BARDA, as well as  the impact of
the sequestration on the federal appropriations provided to BARDA under  the
Reauthorizat ion Act.

Opinion of Leerink Sw ann, page  94

3. We note your description of the  analysis performed by  Leerink Swann  in rendering  its
fairness opinion , which included an estimate of future revenues that PharmAthene may
derive  from  its pending litigation with SIGA Technologies .  We further note that Leerink
assumed  that such future revenues will be equal to the damages awarded to PharmAthene
by the Delaware Chancery Court in its j udgment dated  May 31, 2012 .  Please expand
your description  to disclose :

 the dollar amount of estimated damages attributed to this pending liti gation  for
purpose s of Leerink ’s analysis  and its valuation  of PharmAthene ; and

 the methodology used to derive the estimate  of damages , including , if applicable,
the val ue attributed to the net profits from sales of  SIGA ’s ArestvyrTM

We urge all persons who are responsible for the accuracy and adequacy of the disclosure
in the filing to be certain that the filing includes the information the Securities Act of 193 3 and
all applicable Securities  Act rules require.   Since the company and its management are in
possession of all facts relating to a company’s disclosure, they are responsible for the accuracy
and adequacy of the disclosures they have made.

Notwithstanding our comments, in the event you request acceleration of the effective date
of the pending registration statement please provide a written statement from the company
acknowledging that:

 should the Commission or the staff, acting pursuant to delegated authority, declare the
filing eff ective, it does not foreclose the Commission from taking any action with respect
to the filing;

Mr. Eric Richman
PharmAthene, Inc.
October 1, 2013
Page 3

  the action of the Commission or the staff, acting pursuant to delegated authority, in
declaring the filing effective, does not relieve the company from its fu ll responsibility for
the adequacy and accuracy of the disclosure in the filing; and

 the company may not assert staff comments and the declaration of effectiveness as a
defense in any proceeding initiated by the Commission or any person under the federal
securities laws of the United States.

Please refer to Rules 460 and 461 regarding requests for  acceleration .  We will consider a
written request for acceleration of the effective date of the registration statement as confirmation
of the fact that those r equesting acceleration are aware of their respective responsibilities under
the Securities Act of 1933 and the Securities Exchange Act of 1934 as they relate to the proposed
public offering of the securities specified in the above registration statement.  Please allow
adequate time  for us to review any amendment prior to the requested effective date of the
registration statement.

Please contact Matthew Jones  at (202) 551 -3786, Dan Greenspan at (202) 551 -3623, or
me at (202) 551 -3715  with any other questions.

Sincerely,

 /s/ Daniel Greenspan for

Jeffrey P. Riedler
Assistant Director

cc:  Jeffrey Baumel
 Dentons US LLP
 1221 Avenue of the Americas
 New York, New York 10020 -1089

Via Facsimile and U.S. Mail
Mail Stop 4720

        March 1, 2010

Charles A. Reinhart III
Chief Financial Officer
PharmAthene, Inc.
One Park Place,
Suite 450
Annapolis, MD

 Re: PharmAthene, Inc.
  Form 10-K for the Year Ended December 31, 2008
  Form 10-Q for the Period Ended September 30, 2009
  File No. 001-32587

Dear Mr. Reinhart:

 We have completed our review of your Forms 10-K and 10-Q and have no further
comments at this time.
        S i n c e r e l y ,
           J o e l  P a r k e r          A c c o u n t i n g  B r a n c h  C h i e f

CORRESP
1
filename1.htm

    [Pharmathene
Letterhead]

    February
26, 2010

              Jim
      B. Rosenberg

              Mary
      Mast

              Tabatha
      Akins

              Division
      of Corporation Finance

              United
      States Securities and Exchange Commission

              100
      F Street, N.E.

              Washington,
      D.C. 20549

              Re:

              PharmAthene,
      Inc.

    Form 10-K for the Year Ended December
31, 2008

    Form 10-Q for the Period Ended
September 30, 2009

    File No. 001-32587

    Dear Mr.
Rosenberg, Ms. Mast and Ms. Akins:

    By
letters dated December 22, 2009 and February 3, 2010, you provided comments on
the Annual Report on Form 10-K for the Year Ended December 31, 2008 (“2008
10-K”) and the Quarterly Report on Form 10-Q for the Period Ended September 30,
2009 (“Third Quarter 10-Q”) of PharmAthene, Inc. (the “Company”).  The
Company responded to your comments of December 22, 2009 by letter dated January
22, 2010.  This letter sets forth the Company’s responses to your
comments of February 3, 2010.  For your convenience, we have
reproduced below in italics each comment and have provided the Company’s
response immediately below the comment.

    Form
10-K for the Year Ended December 31, 2008

    Management’s Discussion and
Analysis of Financial Condition and Results of Operations, page
47

    Results of Operations, page
49

    Acquired In-Process Research
and Development, page 52

              1.

              As
      previously requested in part of our prior comment number one, please
      disclose the significant appraisal assumptions, such
  as:

              a.

              the
      period in which material net cash inflows from significant projects are
      expected to commence;

              b.

              material
      anticipated changes from historical pricing, margins and expense levels;
      and

              c.

              the
      risk adjusted discount rate applied to the project’s cash
      flows.

      February
26, 2010

      Page
2

    Response

    In response to parts (a) and (c) of
your comment, the Company proposes to include the following disclosure under
“Acquired In-Process Research and Development” in its annual report on Form 10-K
for the year ended December 31, 2009 (the “2009 10-K”):

    During
the year end December 31, 2008, the Company completed the Avecia
Acquisition.  The primary asset acquired in the Avecia Acquisition was
SparVax™, a second generation rPA anthrax vaccine.  The value of the
third generation anthrax vaccine acquired in the transaction was aggregated with
that of the second generation vaccine because success in developing the third
generation anthrax vaccine is contingent on the successful development of the
second generation vaccine.  At the acquisition date, the aggregate
fair value of the second and third generation vaccines was estimated at $16.1
million.  An income approach methodology was used to determine the
fair value of the acquired in-process research and development
asset.  This approach assessed the expected cash flows, net of
expected appropriate operating expenses, generated from the acquisition date in
April 2008 through the end of 2021 (the expected life of the vaccine) using a
risk adjusted discount rate of 51%, which the Company believes is commensurate
with an early stage biodefense product development opportunity of this
nature.  In connection with the transaction, the Company in 2008
recorded a charge to expense for acquired in-process research and development of
$16.1 million for these acquired research projects for which, at the acquisition
date, technological feasibility had not been established and no alternative
future use existed.  No such charge was recorded in 2009.

    Both
vaccines are in their early stages of development and significant remaining
research and development is required to establish the technological feasibility
of these vaccines.  The cost and time required to complete the
development of these vaccines and earn FDA marketing approval is highly
uncertain and can vary significantly.  During 2009, we provided the US
Government with a series of development plans for SparVax™, in response to their request
for proposal, which estimated that it would cost in excess of $300 million over
approximately 5 years to complete the development of SparVax™.  No such estimates
of the advanced development costs and timeline for the third generation vaccine
have been developed.

    As with
all development efforts in the biodefense industry, the development of our
second and third generation anthrax vaccines is subject to delays, as described
in “Risk Factors—Necessary
Reliance on the Animal Rule in Conducting Trials is Time-Consuming and
Expensive” and “—We
have not commercialized any products or recognized any revenues from
sales.  All of our product candidates are still under development, and
there can be no assurance of successful commercialization of any of our
products.”  Our development costs will increase substantially if we
experience material delays in any clinical trials or if we need to conduct more
or larger trials than planned.

        February
26, 2010

        Page
3

    In response to part (b) of your
comment, the Company respectfully advises the Staff that, since SparVax™ and the
Company’s third generation anthrax vaccine both represented early stage product
development opportunities at their time of acquisition, and therefore had not
yet reached the stage of commercialization, no historical pricing and margin
levels existed at the time of acquisition, nor do they presently
exist.  Furthermore, the Company does not have information on
historical expense levels that the vaccines’ previous owner, Avecia Biologics
Limited, incurred in connection with the vaccines and is therefore unable to
determine to what extent its own expense assumptions were different from
historical levels.

    Index to Consolidated
Financial Statements, page F-1

    Note 2 - Summary of
Significant Accounting Policies, F-10

    Revenue Recognition, page
F-14

              2.

              Please
      refer to your response to our prior comment number two.  It is
      still unclear what is meant by the statement “an estimate of the
      applicable fees.”  Please revise to clarify how the estimate of
      applicable fees is determined.  Further, you state “fixed fees
      under cost-plus-fee contracts to be earned in proportion to the allowable
      costs.”  Please revise to clarify what specific drivers of the
      allowable costs are used to estimate the proportion of revenues
      earned.

    Response

    In response to your comment, the
Company proposes to include the following disclosure under “Revenue Recognition”
in the 2009 10-K:

    The
Company generates its revenue from two different types of contractual
arrangements: cost-plus-fee contracts and cost reimbursable
grants.  Costs consist primarily of actual internal labor charges and
external sub-contractor costs incurred plus an allocation of applied fringe
benefits, overhead and general and administrative expenses as defined in the
contract.  Revenues on cost-plus-fee contracts are recognized in an
amount equal to the costs incurred during the period plus an estimate of the
applicable fee earned.  The estimate of the applicable fee earned is
determined by reference to the contract:  If the contract defines the fee in terms of risk-based
milestones and specifies the fees to be earned upon the completion of each
milestone, the fee income is recognized when the related milestones are
earned.  Otherwise, the Company
computes fee income earned in a given period by using a proportional performance method based on
costs incurred during the period as compared to total estimated project costs
and application of the resulting fraction to the total project fee specified in
the contract.

        February
26, 2010

        Page
4

    If you
have any questions, or if we may be of any assistance, please do not hesitate to
contact the undersigned at (410) 269-2600 or Jeffrey Baumel or Roland Chase at
our outside counsel, Sonnenschein Nath & Rosenthal LLP, at (973)
912-7100.

              Very
      truly yours,

              /s/ Charles A.
      Reinhart III

              Charles
      A. Reinhart III

              Senior
      Vice President and Chief Financial
  Officer

              Cc:

              Jordan
      P. Karp, Esq., PharmAthene, Inc.

CORRESP
1
filename1.htm

    Unassociated Document

              [SNR
      LETTERHEAD]

              101 JFK Parkway

              Short Hills, NJ 07078-2708

              973.912.7100

              973.912.7199 fax

              www.sonnenschein.com

      Roland
S. Chase

      973.912.7179

      rchase@sonnenschein.com

      February
18, 2010

      VIA
EDGAR

                Mr.
      Jim B. Rosenberg

                Ms.
      Mary Mast

                Ms.
      Tabatha Akins

                United
      States Securities and Exchange Commission

                Division
      of Corporation Finance

                Mail
      Stop 4720

                100
      F Street, N.E.

                Washington,
      DC  20549

                Re:

                PharmAthene,
      Inc.

                Form
      10-K For the Year Ended December 31, 2008

                Form
      10-Q For the Quarterly Period Ended September 30, 2009

                File
      No. 001-32587

      Dear Mr.
Rosenberg, Ms. Mast and Ms. Akins:

      By letter
dated February 3, 2010, you provided comments on the above-referenced filings of
PharmAthene, Inc. (the “Company”).  The Company is currently working
on the responses to your comments and expects to submit its response letter via
EDGAR on or before February 26, 2010.

      If you
have any questions, or if we may be of any assistance, please do not hesitate to
contact the undersigned or Jeffrey Baumel of Sonnenschein Nath & Rosenthal
LLP, the Company’s outside counsel, at (973) 912-7100.

      Sincerely,

      /s/
Roland S. Chase

      Roland S.
Chase

      Associate

                Cc:

                Jordan
      P. Karp, Esq., Senior Vice President and General
  Counsel

      Charles
A. Reinhart III, Senior Vice President and Chief Financial
Officer

      Brussels            Chicago            Dallas            Kansas
City            Los
Angeles            New
York            Phoenix            St.
Louis

      San
Francisco            Short
Hills,
N.J.            Silicon
Valley         Washington,
D.C.            Zurich

Via Facsimile and U.S. Mail
Mail Stop 4720

        February 3, 2010

Charles A. Reinhart III
Chief Financial Officer
PharmAthene, Inc.
One Park Place,
Suite 450
Annapolis, MD

 Re: PharmAthene, Inc.
  Form 10-K for the Year Ended December 31, 2008
  Form 10-Q for the Period Ended September 30, 2009
  File No. 001-32587

Dear Mr. Reinhart:

 We have reviewed your January 22, 2010 response to our December 22, 2009
comment letter and have the following comment s.  In our comments, we ask you to provide
us with information to better understand your disclosure.  Where a comment requests you
to revise disclosure, the information you provide should show us what the revised
disclosure will look like and identify the annua l or quarterly filing, as applicable, in which
you intend to first include it.  If you do not believe that revi sed disclosure is necessary,
please explain the reason in your response.  After reviewi ng the information provided, we
may raise additional comments and/or request that you amend your filings.

Form 10-K for the Year Ended December 31, 2008

Management’s Discussion and Analysis of Financial Condition and Results of
Operations, page 47
 Results of Operations, page 49

 Acquired In-Process Research and Development, page 52

1. As previously requested in part f our prior comment number one, please disclose
the significant appraisal assumptions, such as:

Charles A. Reinhart III
PharmAthene, Inc. February 3, 2010 Page 2
a. the period in which material net cash  inflows from signi ficant projects are
expected to commence;
b. material anticipated changes from hi storical pricing, margins and expense
levels; and
c. the risk adjusted discount rate a pplied to the project’s cash flows.
 Index to Consolidated Financial Statements, page F-1

 Note 2 - Summary of Significant Accounting Policies, F-10

 Revenue Recognition, page F-14

2. Please refer to your response to our prior comment number two.  It is still unclear
what is meant by the statement “an estimate of the applicable fees”.  Please revise
to clarify how the estimate of applicable fees is determined.  Further, you state
“fixed fees under cost-plus-fee contract s to be earned in proportion to the
allowable costs”.  Please re vise to clarify what specifi c drivers of the allowable
costs are used to estimate the proportion of revenues earned.

* * *

Please provide us the information requested within 10 business days  of the date of
this letter or tell us when you will provide a response prior to the expiration of the 10-day
period.  Please furnish a letter with your responses that keys your response to our
comments.  Detailed letters gr eatly facilitate our review.  You should furnish the letter on
EDGAR under the form type label CORRESP.

You may contact Tabatha Akins, Staff Accountant, at (202) 551-3658 or Mary
Mast, Senior Staff Accountant, at (202) 551-3613, if you have questions regarding the
comments.  In this regard, do not hes itate to contact me, at (202) 551-3679.

        S i n c e r e l y ,

        J i m  B .  R o s e n b e r g
Senior Assistant Chief
Accountant

CORRESP
1
filename1.htm

[Pharmathene Letterhead]

January 22, 2010

Jim
B. Rosenberg

Mary
Mast

Tabatha
Akins

Division
of Corporation Finance

United
States Securities and Exchange Commission

100
F Street, N.E.

Washington,
D.C. 20549

  Re:

  PharmAthene, Inc.

  Form 10-K
  for the Year Ended December 31, 2008

  Form 10-Q
  for the Period Ended September 30, 2009

  File
  No. 001-32587

Dear Mr. Rosenberg, Ms. Mast
and Ms. Akins:

By letter dated December 22, 2009, you provided
comments on the Form 10-K for the Year Ended December 31, 2008 (“2008
10-K”) and the Form 10-Q for the Period Ended September 30, 2009 (“Third
Quarter 10-Q”) of PharmAthene, Inc. (the “Company”).  This letter sets forth the Company’s
responses to such comments.  For your
convenience, we have reproduced below in italics each comment and have provided
the Company’s response immediately below the comment.

Form 10-K for the Year Ended December 31, 2008

Management’s Discussion and Analysis of Financial Condition and Results
of Operations, page 47

Results of Operations, page 49

Acquired In-Process Research and Development, page 52

1.              Please disclose the following information relating to the in-process
research and development acquired:

a.              Disclose the specific nature and fair value of each significant
in-process research and development project acquired.

b.              Disclose the completeness, complexity and uniqueness of the projects at
the acquisition date.

c.               Disclose the nature, timing and estimated costs of the efforts
necessary to complete the projects, and the anticipated completion dates.

d.              Explain the risks and uncertainties associated with completing
development on schedule, and consequences if it is not completed timely.

e.               Disclose what appraisal method was used to value the projects.

f.                  Disclose the significant appraisal assumptions, such as:

i.                 the period in which material net cash inflows from significant projects
are expected to commence;

ii.             material anticipated changes from historical pricing, margins and
expense levels; and

iii.         the risk adjusted discount rate applied to the project’s cash flows.

g.              In periods after a significant write-off, discuss the status of efforts
to complete the projects, and the impact of any delays on your expected
investment return, results of operations and financial condition.

Response

In
response to your comment, the Company proposes to replace the paragraph
appearing under “Acquired In-Process research and Development” on page 52
of the 2008 10-K with the following disclosure in its annual report on Form 10-K
for the year ended December 31, 2009 (the “2009 10-K”):

During
the year end December 31, 2008, the Company completed the Avecia
Acquisition.  The primary asset acquired
in the Avecia Acquisition was SparVax™, a second generation rPA anthrax
vaccine.  The value of the third
generation anthrax vaccine acquired in the transaction was aggregated with that
of the second generation vaccine because success in developing the third
generation anthrax vaccine is contingent on the successful development of the
second generation vaccine.  At the
acquisition date, the aggregate fair value of the second and third generation
vaccines was estimated at $16.1 million.
An income approach methodology was used to determine the fair value of
the acquired in-process research and development asset.  This approach assessed the expected cash
flows, net of expected appropriate operating expenses, generated from the
acquisition date through the end of 2021 (the expected life of the vaccine)
using a risk adjusted discount rate commensurate with an early stage,
bio-defense product development opportunity.
In connection with the transaction, the Company recorded a charge to
expense for acquired in-process research and development of $16.1 million for
these acquired research projects for which, at the acquisition date,
technological feasibility had not been established and no alternative future
use existed.

Both
vaccines are in their early stages of development and significant remaining
research and development is required to establish the technological feasibility
of these vaccines.  The cost and time
required to complete the development of these vaccines and earn FDA marketing
approval is highly uncertain and can vary significantly.  During 2009, we provided the US Government
with a series of development plans for SparVax™, in response to their
request for proposal, which estimated that it would cost in excess of $300
million over approximately 5 years to complete the development of SparVax™.

2

No
such estimates of the advanced development costs and timeline for the third
generation vaccine have been developed.

As
with all development efforts in the biodefense industry, the development of our
second and third generation anthrax vaccines is subject to delays, as described
in “Risk Factors—Necessary Reliance on the
Animal Rule in Conducting Trials is Time-Consuming and Expensive”
and “—We have not
commercialized any products or recognized any revenues from sales.  All of
our product candidates are still under development, and there can be no
assurance of successful commercialization of any of our products.”
Our development costs will increase substantially if we experience material
delays in any clinical trials or if we need to conduct more or larger trials
than planned.

Index to Consolidated Financial Statements, page F-1

Note 2 - Summary of Significant Accounting Policies, F-10

Revenue Recognition, page F-14

2.                                      Your disclosure of recognizing revenue from cost-plus-fee contracts “to
the extent of costs incurred plus an estimate of the applicable fees” is vague.
Please revise to clarify when revenue is recognized and how the amount is
determined. Also disclose how costs incurred under these agreements are
measured and how the applicable fees are estimated.

Response

In
response to your comment, the Company proposes to replace the first three
sentences of the first paragraph under the “Revenue Recognition” section on page F-14
of the 2008 10-K with the following disclosure in its annual report on Form 10-K
for the year ended December 31, 2009 (the “2009 10-K”):

The
Company generates its revenue from two different types of contractual
arrangements: cost-plus-fee contracts and cost reimbursable grants.  Costs consist primarily of actual internal
labor charges and external sub-contractor costs incurred plus an allocation of
applied fringe benefits, overhead and general and administrative expenses as
defined in the contract.  Revenues on
cost-plus-fee contracts are recognized in an amount equal to the costs incurred
during the period plus an estimate of the applicable fee earned (also as
defined in the contract).  The Company
considers fixed fees under cost-plus-fee contracts to be earned in proportion
to the allowable costs incurred in performance of the contract.

3

Form 10-Q for the Period Ended September 30, 2009

Item 2.  Management’s Discussion
and Analysis of Financial Condition and Results of Operations, page 13

Liquidity and Capital Resources, page 19

Operating Activities, page 20

3.                                      We note that your unbilled receivables increased $12.9 million between December 31,
2008 and September 30, 2009. Please revise to disclose the billing terms
and to explain why you believe that collectability of the unbilled receivable
is assured.

Response

In
response to your comment, the Company proposes to add the following disclosure
to the section “Liquidity and Capital Resources--Operating Activities” in the
2009 10-K:

During
2009, our development agreement for SparVax™, our second generation rPA anthrax
vaccine, was (1) transferred from NIH to BARDA, (2) novated from our
UK subsidiary to the U.S. parent corporation, PharmAthene, Inc., and (3) revised
with regard to the scope and timing of work under that agreement.  During the period that the changes to our
second generation rPA anthrax vaccine contract were being implemented, we
agreed with the U.S. Government to delay invoicing under that contract, which
resulted in a significant increase in “Other receivables (including unbilled
receivables)”. We believe that these unbilled receivables represent valid,
chargeable program expenses and expect them to be invoiced and collected during
2010.

*                                                                              *                                                                              *

The Company hereby acknowledges that:

·                  the Company is responsible for the adequacy
and accuracy of the disclosure in the filings;

·                  comments by the staff (the “Staff”) of the
Securities and Exchange Commission (the “Commission”) or changes to disclosure
in response to Staff comments do not foreclose the Commission from taking any
action with respect to the filings; and

·                  the Company may not assert Staff comments as
a defense in any proceeding initiated by the Commission or any person under the
federal securities laws of the United States.

4

If you have any questions, or if we may be of any
assistance, please do not hesitate to contact the undersigned at (410) 269-2600
or Jeffrey Baumel or Roland Chase at our outside counsel, Sonnenschein Nath &
Rosenthal LLP, at (973) 912-7100.

  Very
  truly yours,

  /s/
  Charles A. Reinhart III

  Charles
  A. Reinhart III

  Senior
  Vice President and Chief Financial Officer

  Cc:     Jordan
  P. Karp, Esq., PharmAthene, Inc.

5

CORRESP
1
filename1.htm

[PHARMATHENE LETTERHEAD]

January 5, 2010

VIA
EDGAR

Mr.
Jim B. Rosenberg

Ms.
Mary Mast

Ms.
Tabatha Akins

United
States Securities and Exchange Commission

Division
of Corporation Finance

Mail
Stop 4720

100
F Street, N.E.

Washington,
DC  20549

  Re:

  PharmAthene,
  Inc.

  Form 10-K
  For the Year Ended December 31, 2008

  Form 10-Q
  For the Quarterly Period Ended September 30, 2009

  File No. 001-32587

Dear Mr. Rosenberg, Ms. Mast
and Ms. Akins:

By letter dated December 22,
2009, you provided comments on the above-referenced filings of PharmAthene, Inc.
(the “Company”).  The Company is
currently working on the responses to your comments and expects to submit its
response letter via EDGAR on or before January 29, 2010.

If you have any questions,
or if we may be of any assistance, please do not hesitate to contact the
undersigned at (410) 269-2600 or Jeffrey Baumel or Roland Chase at our outside
counsel, Sonnenschein Nath & Rosenthal LLP, at (973) 912-7100.

  Sincerely,

  /s/
  Charles A. Reinhart III

  Charles
  A. Reinhart III

  Senior Vice President and Chief Financial Officer

Cc:   Jordan P. Karp, Esq.,
Senior Vice President and General Counsel

Via Facsimile and U.S. Mail
Mail Stop 4720

        December 22, 2009

Charles A. Reinhart III
Chief Financial Officer
PharmAthene, Inc.
One Park Place,
Suite 450
Annapolis, MD

 Re: PharmAthene, Inc.
  Form 10-K for the Year Ended December 31, 2008
  Form 10-Q for the Period Ended September 30, 2009
  File No. 001-32587

Dear Mr. Reinhart:

 We have reviewed your filings and have the following comments.  We have
limited our review of your filings to your fina ncial statements and related disclosures and
do not intend to expand our review to other por tions of your document.   In our comments,
we ask you to provide us with information to  better understand your disclosure.  Where a
comment requests you to revise disclosure, the information you provide should show us
what the revised disclosure will look like a nd identify the annual or quarterly filing, as
applicable, in which you intend to first incl ude it.  If you do not believe that revised
disclosure is necessary, please explain the reason in your re sponse.  After reviewing the
information provided, we may raise additiona l comments and/or request that you amend
your filings.

Please understand that the purpose of our re view process is to assist you in your
compliance with the applicable disclosure requirements and to enhance the overall
disclosure in your filings.  We look forward to working with you in these respects.  We
welcome any questions you may have about our  comments or any other aspect of our
review.  Feel free to call us at the telephone numbers listed at the end of this letter.

Charles A. Reinhart III
PharmAthene, Inc. December 22, 2009 Page 2
 Form 10-K for the Year Ended December 31, 2008

Management’s Discussion and Analysis of Financial Condition and Results of
Operations, page 47
 Results of Operations, page 49

 Acquired In-Process Research and Development, page 52

1. Please disclose the following information relating to the in-process research and
development acquired:
 a. Disclose the specific nature and fair  value of each significant in-process
research and development project acquired.

b. Disclose the completeness, complexity  and uniqueness of the projects at
the acquisition date.

c. Disclose the nature, timing and estimate d costs of the efforts necessary to
complete the projects, and the anticipated completion dates.

d. Explain the risks and uncertainties associated with completing
development on schedule, and conseque nces if it is not completed timely.

e. Disclose what appraisal method wa s used to value the projects.

f. Disclose the significant appr aisal assumptions, such as:

i. the period in which material net cash inflows fr om significant
projects are expected to commence;
ii. material anticipated changes from  historical pricing, margins and
expense levels; and
iii. the risk adjusted discount rate a pplied to the project’s cash flows.

g. In periods after a significant write-o ff, discuss the status of efforts to
complete the projects, and the impact of any delays on your expected investment return, results of ope rations and financial condition.

Charles A. Reinhart III
PharmAthene, Inc. December 22, 2009 Page 3
 Index to Consolidated Financial Statements, page F-1

 Note 2 - Summary of Significant Accounting Policies, F-10

 Revenue Recognition, page F-14

2. Your disclosure of recognizing revenue fr om cost-plus-fee contracts “to the extent
of costs incurred plus an estimate of the a pplicable fees” is vague. Please revise to
clarify when revenue is recognized and how the amount is determined.  Also
disclose how costs incurred under these agreements are measured and how the
applicable fees are estimated.

Form 10-Q for the Period Ended September 30, 2009

Item 2. Management’s Discussion and Analys is of Financial Condition and Results of
Operations, page 13
 Liquidity and Capital Resources, page 19

 Operating Activities, page 20

3. We note that your unbilled receiv ables increased $12.9 million between
December 31, 2008 and September 30, 2009.  Pleas e revise to disclose the billing
terms and to explain why you believe that collectability of the unbilled receivable
is assured.
* * *

Please provide us the information requested within 10 business days  of the date of
this letter or tell us when you will provide a response prior to the expiration of the 10-day
period.  Please furnish a letter with your responses that keys your response to our
comments.  Detailed letters gr eatly facilitate our review.  You should furnish the letter on
EDGAR under the form type label CORRESP.

 We urge all persons who are responsible for the accuracy and adequacy of the
disclosure in the filings to be certain that  the filings includes all information required
under the Securities Exchange Act of 1934 and that they have provided all information
investors require for an informed invest ment decision.  Since the company and its
management are in possession of all facts re lating to a company’s disclosure, they are
responsible for the accuracy and adequacy of the disclosures they have made.

 In connection with responding to our co mments, please provide, in your letter, a
statement from the company acknowledging that:

• the company is responsible for the adequacy  and accuracy of the disclosure in the
filings;

Charles A. Reinhart III
PharmAthene, Inc. December 22, 2009 Page 4
 • staff comments or changes to disclosure  in response to staff comments do not
foreclose the Commission from taking any action with respect to the filings; and
• the company may not assert staff comme nts as a defense in any proceeding
initiated by the Commission or any person under the federal secu rities laws of the
United States.

In addition, please be advise d that the Division of Enfo rcement has access to all
information you provide to the staff of the Divi sion of Corporation Fi nance in our review
of your filings or in response to our comments on your filings.

You may contact Tabatha Akins, Staff Accountant, at (202) 551-3658 or Mary
Mast, Senior Staff Accountant, at (202) 551-3613, if you have questions regarding the
comments.  In this regard, do not hes itate to contact me, at (202) 551-3679.

        S i n c e r e l y ,

        J i m  B .  R o s e n b e r g
Senior Assistant Chief
Accountant

CORRESP
1
filename1.htm

[PharmAthene, Inc.
Letterhead]

November 24, 2009

United States Securities
and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549

  Re:

  PharmAthene, Inc.

  Registration Statement on
  Form S-3,

  as amended on August 31,
  2009 and November 20, 2009

  File
  No. 333-161587

Ladies and Gentlemen:

PharmAthene, Inc.
(the “Company”) hereby acknowledges that:

·                  the Company is responsible for the
adequacy and accuracy of the disclosure in the filings;

·                  comments by the staff (the “Staff”) of
the Securities and Exchange Commission (the “Commission”) or changes to
disclosure in response to Staff comments in the filings reviewed by the Staff
do not foreclose the Commission from taking any action with respect to the
filing; and

·                  the Company may not assert Staff comments
as a defense in any proceeding initiated by the Commission or any person under
the federal securities laws of the United States.

Pursuant
to Rule 461(a) under the Securities Act of 1933, as amended, the
Company hereby requests acceleration of the effective date of its Registration
Statement on Form S-3, as amended (File No. 333-161587), under said Act,
so that the same will be declared effective on Wednesday, November 25,
2009 at noon, Washington, D.C. time, or as soon thereafter as practicable.

If you
have any questions or comments, please do not hesitate to contact Jeffrey A.
Baumel, Esq. at (973) 912-7189 or Roland S. Chase, Esq. at (973)
912-7179 at our counsel, Sonnenschein Nath & Rosenthal LLP.

  Very truly yours,

  PharmAthene, Inc.

  By:

  /s/ David Wright

  David Wright

  Chief
  Executive Officer

CORRESP
1
filename1.htm

Jeffrey A. Baumel

973.912.7189

jbaumel@sonnenschein.com

November 16, 2009

Jeffrey
Riedler

Scott
Foley

Division
of Corporation Finance

United
States Securities and Exchange Commission

100
F Street, N.E.

Washington,
D.C. 20549

  Re:

  PharmAthene, Inc.

  Amendment
  No. 1 to Registration Statement on Form S-3

  Filed
  August 31, 2009

  File
  No. 333-161587

Dear Messrs. Riedler
and Foley:

By letter dated September 17, 2009 (the “September Comment
Letter”), the staff (the “Staff”) of the Securities and Exchange Commission
(the “Commission”) provided comments on Amendment No. 1 to Registration
Statement on Form S-3 filed by PharmAthene, Inc. (the “Company”) with
the Commission on August 31, 2009 (File No. 333-161587) (the “Registration
Statement”).  The Company responded to
such comments by letter dated October 14, 2009 (the “October Response
Letter”).  By letter dated November 6,
2009 (the “November Comment Letter”), the Staff provided further comments
on Amendment No. 1 to the Registration Statement.

This letter sets forth the Company’s responses to
the Staff’s comments contained in the November Comment Letter.  For your convenience, we have reproduced
below in italics each comment and have provided the Company’s response
immediately below the comment.  Terms
used but not defined herein have the meaning specified in the October Response
Letter.

Form S-3

General

1.                                      We note your
response to comment 1.  After careful
consideration of your analysis, we are unable to concur with your conclusion
that your proposed transaction should be treated as a secondary offering.  We understand that the conversion price is
not a discount to the market price and that the conversion price does not
adjust relative to the market price of the underlying common stock.

Brussels            Chicago            Dallas            Kansas City            Los Angeles            New York            Phoenix            St. Louis

San Francisco            Short Hills, N.J.            Silicon Valley         Washington, D.C.            Zurich

Our conclusion that the offering is a primary
offering is due to the fact that you are registering the resale of shares
constituting 85.1% of your current public float.  Given the size relative to the number of
shares outstanding held by non-affiliates, the nature of the offering and the
selling security holders, the transaction appears to be a primary
offering.  Please revise your
registration statement onto a form you are eligible to use for a primary
offering, identify the selling shareholders as underwriters and set a price for
the offering.  Alternatively, reduce the
size of your offering.

Response:

In light of the November 25, 2009 deadline for
effectiveness of the Registration Statement imposed by the Registration Rights
Agreement, the Company will reduce the number of shares included in the
Registration Statement to an amount equal to one-third of the number of shares
outstanding immediately prior to the Financing that were held by non-affiliates
of the Company, by amending the Registration Statement in Amendment No. 2
(“Amendment No. 2”) to register for resale one-third of 13,747,978 shares,
which represented the Company’s public float immediately prior to the
Financing, or 4,582,659 shares.  We
understand that the Staff is considering whether it may be appropriate for the
Company to register a greater number of shares, and if such a determination is
made, the Company will either amend the Registration Statement or file a new
registration statement, as appropriate.

2.                                      We note your
responses to comments 4 and 5.  We
understand that the market price at the time of the transaction was less than
the conversion price and that a conversion at the time would have resulted in a
loss.  Please present the requested
information showing the loss the security holders would realize as a result of
a conversion.

Response:

In response to the Staff’s comment 2, the
Company proposes to add the disclosure appearing below to Amendment No. 2:

Possible Profit/(Loss) to
Selling Stockholders with Respect to Conversion or Exercise of Company
Securities

The tables below summarize the total possible
profit/(loss) that the selling stockholders or their affiliates could have
realized as a result of (a) the conversion of the 10% Convertible Notes, (b) the
exercise of the related warrants and (c) the exercise of any options to
purchase our

2

common stock, assuming
conversion or exercise on the date of sale or date of grant, as applicable:

  Security

  Market

  price per

  share on

  date of

  sale(1)

  Conversion

  price per

  share(2)

  Total

  number of

  underlying

  shares(3)

  Combined

  market price

  of total

  number of

  underlying

  shares

  Combined

  conversion

  price of total

  number of

  underlying

  shares

  Total

  possible

  profit/(loss)

  realizable by

  selling

  stockholders

  10%
  Convertible Notes

  $

  2.50

  $

  2.541667

  9,131,235

  $

  22,828,087.50

  $

  23,208,558.67

  $

  (380,471.17

  )

  (1)

  Represents the closing
  price per share of our common stock on the NYSE Amex on July 24, 2009,
  the trading day immediately preceding the time that we entered into the
  binding agreement to issue the 10% Convertible Notes and related warrants.

  (2)

  The conversion price is
  subject to customary antidilution adjustments, including in the event of a
  stock dividend, stock split or stock combination, recapitalization or
  reorganization, merger or consolidation, sale of all or substantially all of
  our assets, distribution of debt or assets to our stockholders and in
  connection with certain other dilutive equity issuances.

  (3)

  This amount includes (a) up to 7,591,790 shares
  issuable upon conversion of the aggregate principal amount of the 10%
  Convertible Notes, and (b) up to 1,539,445 shares issuable in respect of
  interest that has begun accruing and will continue to accrue throughout the
  term of the notes.

  Security

  Market
  price

  per share on

  date of sale(1)

  Exercise

  price per

  share (2)

  Total

  number of

  underlying

  shares

  Combined

  market price

  of total

  number of

  underlying

  shares

  Combined

  exercise

  price of total

  number of

  underlying

  shares

  Total

  possible

  profit/(loss)

  realizable by

  selling

  stockholders

  Warrants
  related to 10% Convertible Notes

  $

  2.50

  $

  2.50

  2,572,775

  $

  6,431,937.50

  $

  6,431,937.50

  $

  0.00

3

  (1)

  Represents the closing
  price per share of our common stock on the NYSE Amex on July 24, 2009,
  the trading day immediately preceding the time that we entered into the
  binding agreement to issue the 10% Convertible Notes and related warrants.

  (2)

  The exercise price is
  subject to customary antidilution adjustments, including in the event of a
  stock dividend, stock split or stock combination, recapitalization or
  reorganization, merger or consolidation, sale of all or substantially all of
  our assets, distribution of debt or assets to our stockholders and in
  connection with certain other dilutive equity issuances.

  Selling

  Stockholder

  Option

  Grant

  Date

  Market

  price

  per

  share on

  grant

  date

  Exercise

  price per

  share on

  grant

  date

  Total

  number of

  underlying

  shares

  Combined

  market

  price of

  total

  number of

  underlying

  shares

  Combined

  exercise

  price of

  total

  number of

  underlying

  shares

  Total
  possible

  profit/(loss)

  realizable by

  selling

  stockholder/

  affiliate

  1/4/2007

  $

  3.80

  $

  3.80

  44,172

  $

  167,854

  $

  167,854

  $

  0

  Chris
  Camut

  10/2/2007

  $

  5.20

  $

  5.20

  215,000

  $

  1,118,000

  $

  1,118,000

  $

  0

  1/21/2009

  $

  2.46

  $

  2.46

  25,308

  $

  62,258

  $

  62,258

  $

  0

  Healthcare
  Ventures VII, L.P.(1)

  9/11/2003

  $

  2.96

  $

  2.96

  1,655

  $

  4,899

  $

  4,899

  $

  0

  1/18/2006

  $

  3.80

  $

  3.80

  1,104

  $

  4,195

  $

  4,195

  $

  0

  10/9/2007

  $

  5.25

  $

  5.25

  20,000

  $

  105,000

  $

  105,000

  $

  0

  3/9/2009

  $

  2.53

  $

  2.59

  10,000

  $

  25,300

  $

  25,900

  $

  (600

  )

  8/5/2009

  $

  2.47

  $

  2.47

  20,000

  $

  49,400

  $

  49,400

  $

  0

  Joel
  McCleary

  9/11/2003

  $

  2.96

  $

  2.96

  1,655

  $

  4,899

  $

  4,899

  $

  0

  1/18/2006

  $

  3.80

  $

  3.80

  1,104

  $

  4,195

  $

  4,195

  $

  0

  10/9/2007

  $

  5.25

  $

  5.25

  20,000

  $

  105,000

  $

  105,000

  $

  0

  4/28/2008

  $

  2.97

  $

  2.97

  50,000

  $

  148,500

  $

  148,500

  $

  0

  3/9/2009

  $

  2.53

  $

  2.59

  10,000

  $

  25,300

  $

  25,900

  $

  (600

  )

  8/5/2009

  $

  2.47

  $

  2.47

  20,000

  $

  49,400

  $

  49,400

  $

  0

  MPM(2)

  1/18/2006

  $

  3.80

  $

  3.80

  1,104

  $

  4,195

  $

  4,195

  $

  0

  10/9/2007

  $

  5.25

  $

  5.25

  20,000

  $

  105,000

  $

  105,000

  $

  0

  3/9/2009

  $

  2.53

  $

  2.59

  10,000

  $

  25,300

  $

  25,900

  $

  (600

  )

  8/5/2009

  $

  2.47

  $

  2.47

  20,000

  $

  49,400

  $

  49,400

  $

  0

  Mary
  Pappajohn(3)

  10/9/2007

  $

  5.25

  $

  5.25

  20,000

  $

  105,000

  $

  105,000

  $

  0

  3/9/2009

  $

  2.53

  $

  2.59

  10,000

  $

  25,300

  $

  25,900

  $

  (600

  )

  8/5/2009

  $

  2.47

  $

  2.47

  20,000

  $

  49,400

  $

  49,400

  $

  0

  Eric
  Richman

  11/15/2003

  $

  2.96

  $

  2.96

  28,638

  $

  84,768

  $

  84,768

  $

  0

  1/18/2005

  $

  3.80

  $

  3.80

  11,043

  $

  41,963

  $

  41,963

  $

  0

  2/22/2006

  $

  3.80

  $

  3.80

  4,510

  $

  17,138

  $

  17,138

  $

  0

4

  Selling

  Stockholder

  Option

  Grant

  Date

  Market

  price

  per

  share on

  grant

  date

  Exercise

  price per

  share on

  grant

  date

  Total

  number of

  underlying

  shares

  Combined

  market

  price of

  total

  number of

  underlying

  shares

  Combined

  exercise

  price of

  total

  number of

  underlying

  shares

  Total
  possible

  profit/(loss)

  realizable by

  selling

  stockholder/

  affiliate

  1/4/2007

  $

  3.80

  $

  3.80

  8,282

  $

  31,472

  $

  31,472

  $

  0

  10/2/2007

  $

  5.20

  $

  5.20

  260,000

  $

  1,352,000

  $

  1,352,000

  $

  0

  1/21/2009

  $

  2.46

  $

  2.46

  30,573

  $

  75,210

  $

  75,210

  $

  0

  Derace
  Schaffer

  10/9/2007

  $

  5.25

  $

  5.25

  20,000

  $

  105,000

  $

  105,000

  $

  0

  3/9/2009

  $

  2.53

  $

  2.59

  10,000

  $

  25,300

  $

  25,900

  $

  (600

  )

  8/5/2009

  $

  2.47

  $

  2.47

  20,000

  $

  49,400

  $

  49,400

  $

  0

  David
  Wright

  7/15/2003

  $

  2.96

  $

  2.96

  82,714

  $

  244,833

  $

  244,833

  $

  0

  1/18/2005

  $

  3.80

  $

  3.80

  69,130

  $

  262,694

  $

  262,694

  $

  0

  2/22/2006

  $

  3.80

  $

  3.80

  13,803

  $

  52,451

  $

  52,451

  $

  0

  1/4/2007

  $

  3.80

  $

  3.80

  16,556

  $

  62,913

  $

  62,913

  $

  0

  8/30/2007

  $

  5.36

  $

  5.36

  780,000

  $

  4,180,800

  $

  4,180,800

  $

  0

  1/21/2009

  $

  2.46

  $

  2.46

  37,185

  $

  91,475

  $

  91,475

  $

  0

(1)                                  Dr. James Cavanaugh is a general
partner of the entity that serves as general partner of Healthcare Ventures
VII, L.P.

(2)                                  Dr. Steven St. Peter is an affiliate
of MPM.

(3)                                  Mary Pappajohn is the wife of John
Pappajohn, the chairman of our Board of Directors..

*  *  *

The Company respectfully advises the Staff that
there are no provisions for adjustment to the Conversion Price based upon
market price, with respect to the 10% Convertible Notes.

5

3.                                      Please revise
your response to comment 6 to include the one-time liquidated damages in the
line item “Payments Made or Required to be Made to Selling Shareholders and
Affiliates.”

The Company proposes to add the disclosure appearing
below to Amendment  No. 2:

Comparison of Proceeds:

  Gross Proceeds from the Sale of the 10%
  Convertible Notes and Warrants(1)

  $

  19,295,802

  Less Payments Made or Required to be Made to
  Selling Stockholders and Affiliates(2)

  $

  4,105,718

  Less Estimated Payments Made or Required to be
  Made to Counsel to MPM and Healthcare Ventures VII, L.P. for certain
  reasonable legal costs and expenses

  $

  75,000

  Resulting Net Proceeds from Sale of the 10%
  Convertible Notes and Warrants(1)

  $

  15,115,084

  Total Possible Discount to Market Price of Stock
  Registered Hereunder

  $

  0

(1)                                  Represents a
combination of canceled debt (8% convertible notes) and new cash. Does not
include $6,431,938 receivable by us upon the full exercise of all warrants.

(2)                                  This
amount reflects interest payments we would owe the selling stockholders assuming
they hold their 10% Convertible Notes through the maturity date, including a
one-time payment of $192,958.02, payable in the event the Company fails to meet
its registration obligations described above, but excluding monthly payments of
$192,958.02, payable each month during which the Company has not cured any
failure to meet its registration obligations. We are unable, at this time, to
estimate the amount of any other payments that may be required to be made to
the selling stockholders in the future.

The total amount of all possible payments payable to
the selling stockholders in connection with the sale of the 10% Convertible
Notes and warrants reflected in the table above, represents approximately 27.1%
of the resulting net proceeds to us from such sale, which is approximately
13.6% per annum averaged over the two-year term of such notes.

6

4.                                      Please revise
the table presented in response to comment 7 to present the requested
information for each selling shareholder rather than presenting the information
in the aggregate.

Response:

The Company proposes to add the disclosure appearing
below to Amendment No. 2:

Prior Securities Transactions

The following table and accompanying footnotes show
information with respect to the prior securities transactions effected between
Healthcare Acquisition Corp. (“HAQ”) and the selling stockholders named in this
prospectus (or their affiliates) since HAQ’s initial public offering in August 2005,
and do not include any grants of stock options or restricted stock made under
our 2007 Long-Term Incentive Compensation Plan, which we refer to as the “2007
Plan.”  Except for grants under the 2007
Plan and the sale of the 10% Convertible Notes and warrants in July 2009,
we have not effected any securities transactions with the selling stockholders
identified in this prospectus (or their affiliates) since merging with HAQ’s
wholly-owned subsidiary in August 2007.

  Selling

  Stockholder

  Common

  stock

  outstanding

  prior to

  transaction

  Common

  stock

  outstanding

  prior to

  transaction

  held by

  persons other

  than selling

  stockholders,

  their affiliates

  or our

  current

  affiliates

  Common

  stock issued

  or issuable

  in

  transaction

  Percentage

  of common

  stock issued

  in the

  transaction

  (based on

  non-

  affiliate

  holdings)(1)

  Closing

  market

  price per

  share of

  common

  stock

  immediately

  prior to

  transaction

  (2)

  Closing

  market

  price per

  share of

  co

Mail Stop 4720       November 6, 2009
Via Facsimile and U.S. Mail

David P. Wright Chief Executive Officer PharmAthene, Inc. One Park Place, Suite 450 Annapolis, Maryland 21401
 Re: PharmAthene, Inc.
  Amendment No. 1 to Registra tion Statement on Form S-3
  Filed August 31, 2009
  File No. 333-161587

Dear Mr. Wright:
We have reviewed your October 14, 2009 res ponse to our September 17, 2009 letter and
have the following comments. Where indicated, we think you should revise your document in
response to these comments. If you disagree, we will consider your explanation as to why our comment is inapplicable or a revision is unnecessa ry. Please be as detailed as necessary in your
explanation. After reviewing this information, we may or may not raise additional comments.
 Please understand that the purpose of our re view process is to assist you in your
compliance with the applicable disclosure requir ements and to enhance the overall disclosure in
your filing. We look forward to working with you in these respects. We welcome any questions
you may have about our comments or on any other as pect of our review. Feel free to call us at
the telephone numbers listed at the end of this letter.
 Form S-3

General

1. We note your response to comment 1. After caref ul consideration of your analysis, we are
unable to concur with your conclusion that your proposed transaction should be treated as
a secondary offering. We understand that the conversion price is not  a discount to the
market price and that the conve rsion price does not adjust re lative to the market price of
the underlying common stock. Our conclusion that the offering is a primary offering is
due to the fact that you are registering the resale of shares constituting 85.1% of your

David P. Wright
PharmAthene, Inc. November 6, 2009
Page 2
current public float. Given the size relative to the number of shar es outstanding held by
non-affiliates, the nature of the offering and the selling security holders, the transaction
appears to be a primary offering. Please revi se your registration statement onto a form
you are eligible to use for a primary offe ring, identify the selling shareholders as
underwriters and set a price for the offe ring. Alternatively, reduce the size of your
offering.

2. We note your responses to comments 4 and 5. We understand that the market price at the
time of the transaction was less than the conve rsion price and that a conversion at that
time would have resulted in a loss. Please pr esent the requested information showing the
loss the security holder s would realize as a result of a conversion.
 3. Please revise your response to comment 6 to  include the one-time liquidated damages in
the line item “Payments Made or Required to be Made to Selling Shareholders and
Affiliates.”

4. Please revise the table presented in res ponse to comment 7 to present the requested
information for each selling shareholder rather  than presenting the information in the
aggregate.

* * *
  As appropriate, please revise your information statement in response to these comments.
You may wish to provide us with marked copies of the revised document to  expedite our review.
Please furnish a response letter th at keys your responses to our co mments.  Detailed cover letters
greatly facilitate our review.  Please file your cover letter on EDGAR under the form type label
CORRESP.  Please understand th at we may have additional comments after reviewing your
amendment and response to our comment.   We urge all persons who are responsible for the accuracy and adequacy of the disclosure in the filings reviewed by the staff to be certain that they have provided all information investors require.  Since the compa ny and its management are in possession of all
facts relating to a company’s disclosure, they are responsible for the acc uracy and adequacy of
the disclosures they have made.   In connection with responding to our comme nts, please provide, in writing, a statement
from the company acknowledging that
• the company is responsible for the adequacy and accuracy of the disclo sure in the filings;

• staff comments or changes to disclosure in response to staff comments in the filings reviewed by the staff do not foreclose th e Commission from taking any action with
respect to the filing; and

David P. Wright
PharmAthene, Inc. November 6, 2009 Page 3
• the company may not assert staff comments as a defense in any proceeding initiated by
the Commission or any person under the federa l securities laws of  the United States.

 In addition, please be advi sed that the Division of En forcement has access to all
information you provide to the sta ff of the Division of Corporati on Finance in our review of your
filing or in response to our comments on your filing.
Please contact Scot Foley, Attorney-Advi sor, at (202) 551-3383, Suzanne Hayes,
Branch Chief, at (202) 551-3675 or me  at (202) 551-3715 with any questions.
        S i n c e r e l y ,            J e f f r e y  R i e d l e r         A s s i s t a n t  D i r e c t o r    cc: Jeffrey A. Baumel, Esq.  Roland S. Chase, Esq.
Sonnenschein Nath & Rosenthal LLP 1221 Avenue of the Americas  New York, New York 10020

CORRESP
1
filename1.htm

  1221 Avenue of the
  Americas

  New York, NY 10020-1089

  212.768.6700

  Jeffrey A. Baumel

  212.768.6800 fax

  973.912.7189

  www.sonnenschein.com

  jbaumel@sonnenschein.com

October 14, 2009

Jeffrey
Riedler

Scott
Foley

Division
of Corporation Finance

United
States Securities and Exchange Commission

100
F Street, N.E.

Washington,
D.C. 20549

Re:                             PharmAthene, Inc.

Amendment No. 1 to Registration Statement on Form S-3

Filed August 31, 2009

File No. 333-161587

Dear Messrs. Riedler
and Foley:

By letter dated September 17, 2009, the staff
(the “Staff”) of the Securities and Exchange Commission (the “Commission”)
provided comments on Amendment No. 1 to Registration Statement on Form S-3
filed by the Company with the Commission on August 31, 2009 (File No. 333-161587)
(the “Registration Statement”).

This letter sets forth the Company’s responses to
the Staff’s comments.  For your
convenience, we have reproduced below in italics each comment and have provided
the Company’s response immediately below the comment.

General

1.                                      We note that
you are registering the sale of 11,704,010 common shares. Given the size
relative to the number of shares outstanding held by non-affiliates, the nature
of the offering and the selling security holders, the transaction appears to be
a primary offering. Because you are not eligible to conduct a primary offering
on Form S-3 you are not eligible to conduct a primary at-the-market
offering under Rule 415(a)(4).

If you disagree with our analysis, please advise the
staff of the company’s basis for determining that the transaction is
appropriately characterized as a transaction that is eligible to be made under Rule 415(a)(1)(i).
In your analysis, please address the following among any other relevant
factors:

Brussels        Chicago        Dallas        Kansas
City        Los Angeles        New
York        Phoenix        St.
Louis

San
Francisco        Short Hills,
N.J.        Silicon Valley        Washington,
D.C.        Zurich

·                  The date on which and the manner in which
each selling shareholder received the shares and/or the overlying securities;

·                  The relationship of each selling shareholder
with the company, including an analysis of whether the selling shareholder is
an affiliate of the company;

·                  Any relationships among the selling
shareholders;

·                  The dollar value of the shares registered in
relation to the proceeds that the company received from the selling
shareholders for the securities, excluding amounts of proceeds that were
returned (or will be returned) to the selling shareholders and/or their
affiliates in fees or other payments;

·                  The discount at which the shareholders will
purchase the common stock underlying the convertible notes (or any related
security, such as a warrant or option) upon conversion or exercise; and

·                  Whether or not any of the selling
shareholders is in the business of buying and selling securities.

Response:

For the reasons set forth below, the Company
respectfully asserts that the offering of securities to be registered pursuant
to the Registration Statement is a valid secondary offering and is eligible to
be made under Rule 415(a)(1)(i) under the Securities Act of 1933 (the
“Act”) as contemplated by the Registration Statement.

Summary
Conclusion — This transaction is not of the type that raises concerns about a
disguised primary offering

The terms of the Financing, in which the Notes and
Warrants (all as defined under “Background” below) were issued, do not include
any price “resets”, floating price conversion rights or other “toxic” features
that have previously prompted the Staff’s concerns regarding “Extreme
Convertible” transactions.  Further, the
Notes and Warrants do not even provide for anti-dilution protection based on
the price of future issuances by the Company.
The only anti-dilution provisions in the Notes and Warrants are
customary “plain vanilla” structural anti-dilution protection provisions in the
event of fundamental organic changes in the Company’s capital structure, such
as stock splits.  These anti-dilution
adjustments are consistent with those that the Staff has previously indicated
on numerous occasions do not raise a concern with respect

2

to the Staff’s interpretation
of Rule 415(1).  As John White,
former Director of Corporation Finance, stated in a speech on February 23,
2007 in Dallas Texas, “I’ll be very clear about this — the staff’s view of PIPE
transactions has not changed; we have simply addressed the recent development
where convertible note transactions are structured in an abusive manner.”

Where a PIPE is not structured in an abusive manner,
the number of shares registered is not a central concern.  However, it bears noting that, while the
total number of shares registered under the Registration Statement represents
85.1% of the Company’s public float, the number of shares actually issuable
upon the closing of the Financing on July 28, 2009, not including the
shares representing interest on the Notes that had not yet accrued or shares
issuable upon exercise of the Warrants that are not exercisable for six months
from the closing, represents only 55.2% of the Company’s public float.  Since the investors would have to hold the
Notes over the long term in order to receive the shares that are issuable in
lieu of interest, and must hold the Warrants for six months in any event, and
the investors will bear full market risk on such securities since they contain
no toxic price reset provisions, the shares issuable in lieu of interest and
upon exercise of the Warrants do not raise the short-term flipping concerns
that might call into question the true nature of a secondary offering.

Additionally, in connection with the Financing, the
Company cancelled its previously issued 8% Notes (as defined below) convertible
into shares representing 5.5% of the Company’s public float, the resale of
which was previously registered. Less than a week after the closing of the
Financing, the remaining 8% Notes, representing another 3.5% of the Company’s
public float, matured and were repaid. As a result, the net addition of shares
issuable upon the closing and subject to registration represents only 46.3% of
the Company’s public float.

Finally, the Financing was priced as an “at-market” deal
for purposes of NYSE Amex rules, i.e., the conversion price of the Notes and
the exercise price of the Warrants are equal to or greater than the closing
price of the Company’s shares on the NYSE Amex immediately preceding the time
that the Company entered into the binding agreement to issue the Notes and
Warrants.  Such closing price also
represents the closing price of the Company’s shares on the NYSE Amex
immediately preceding the public announcement of the Financing by the
Company.  We refer to such closing price
as the “Date of Sale Price.”

At the time of the Financing, an investment bank
evaluated market conditions for financing alternatives and the only available
financing alternative was on terms significantly less favorable to the
Company.  Accordingly, not only does the
Financing not have the type of toxic price reset provisions that trigger a Rule 415
concern, the financial terms of the Financing were very reasonable.

(1) See Speech by John
W. White, Director, Division of Corporation Finance, February 23, 2007;
Keller, Stanley and Hicks, William, “Unblocking Clogged PIPEs: SEC Focuses on
Availability of Rule 415,” Insights, May 2007.

3

Since the Financing was not a toxic reset deal, the
number of shares issuable as of the closing was only 55.2% of the public float
(and 46.3% net of the shares underlying the cancelled and matured 8% Notes) and
the shares are not issuable at a discount, this deal is not the type of abusive
transaction that the Securities and Exchange Commission (the “SEC”) is
concerned about and the registration of the shares issuable under the Financing
should not be considered a primary offering by the Company.

Background

On July 28, 2009, the Company issued, in a
private placement (the “Financing”), the 10% convertible notes due July 28,
2011 (the “Notes”) and related warrants (the “Warrants”) to purchase up to
2,572,775 shares of the Company’s common stock, par value $0.0001 per share
(the Common Stock”) to (i) holders (the “Existing Noteholders”) of then
outstanding 8% senior unsecured convertible notes, due August 3, 2009 (the
“8% Notes”), in lieu of a cash payment covering principal and accrued interest
on the 8% Notes, in the aggregate amount of $8,767,606, and (ii) certain
other new investors (collectively with the Existing Noteholders, the “Investors”)
for $10,528,196 in cash.

The Notes mature on July 28, 2011 (the “Maturity
Date”) and are immediately convertible into shares of Common Stock at a
conversion price of $2.541667 per share (the “Conversion Price”).  Interest on each Note accrues over the term
of the Note at a rate of 10% per annum and, in the event of a conversion, is
converted into Common Stock along with the principal amount of such Note.  The Warrants are exercisable for shares of
Common Stock from January 28, 2010 through January 28, 2015, at an
exercise price of $2.50 per share (the “Exercise Price”).  The closing price of the Common Stock on the
NYSE Amex immediately preceding the time that the Company entered into the
binding agreement to issue the Notes and Warrants was $2.50 per share.

The maximum number of shares of Common Stock (the “Shares”)
into which the Notes and the Warrants can be converted or exercised, as
applicable, assuming conversion of all of the Notes on the Maturity Date, is
11,704,010.  Of that amount, up to
7,591,790 shares are issuable upon conversion of the aggregate principal amount
of the Notes, up to 1,539,445 shares are issuable in respect of interest that
has begun accruing and will continue to accrue throughout the term of the Notes
and up to 2,572,775 shares are issuable upon exercise of the Warrants.

In connection with the Financing, the Company and
the Investors entered into a note and warrant purchase agreement, dated as of July 24,
2009 and as amended as of July 26, 2009 and July 28, 2009 (as so
amended, the “Note and Warrant Purchase Agreement”).   The Company and the Investors also entered
into a registration rights agreement (the “Registration Rights

4

Agreement”), which provides
the Investors with, among other things, registration rights covering the
Shares.  The Registration Rights
Agreement requires the Company to file with the SEC a registration statement
covering such shares within 30 days after closing of the Financing and to use
its best efforts to cause the registration statement to become effective no
later than 90 days after closing, or 120 days in case the SEC reviews the
registration statement.

The Investors in the Financing were:

·                  Baker Bros. Investments II, L.P., Baker
Brothers Life Sciences, L.P. and 14159, L.P. (collectively, “Baker Brothers”);

·                  MPM Asset Management Investors 2004 BVIII
LLC, MPM Bioventures III, LP, MPM Bioventures III GmbH & Co.
Beteiligungs KG, MPM Bioventures III Parallel Fund, LP and MPM Bioventures
III-QP, LP. (collectively, “MPM”);

·                  Healthcare Ventures VII, LP (“HCV”);

·                  Ontario Teachers’ Pension Plan Board;

·                  Mary Pappajohn;

·                  Derace Schaffer;

·                  James Desnick;

·                  Edward Heil;

·                  Argyris (R.J.) Vassiliou;

·                  The Ann Vassiliou Children’s Trust;

·                  Jerome Parks;

·                  Joel McCleary;

·                  David Wright;

·                  Eric Richman; and

·                  Christopher Camut.

Of the $19,295,802 in aggregate principal amount of
Notes and Warrants to purchase 2,572,775 shares issued in the Financing, Notes
in the aggregate principal amount of $9,706,270 and Warrants to purchase
1,294,170 shares of Common Stock (representing approximately 50.3% of the
Financing and the Shares), were issued to persons that, as of the date of this
letter, are deemed to be “affiliates” of the Company (“Affiliates”), as that
term is defined in Rule 405 under the Act (“Rule 405”) and using the
definition of “beneficial ownership” in Rule 13d-3

5

under the Securities
Exchange Act of 1934, as amended (the “Exchange Act”).  The Investors deemed to be Affiliates(2) are:

·                  MPM, beneficial owner of 18.59% of the Common
Stock, has the right to designate a nominee for director on the Company’s Board
of Directors (the “Board”).  Dr. Steven
St. Peter, a director of the Company, is affiliated with MPM but is not a
member of the general partners and thus is not deemed to have beneficial
ownership of the shares of Common Stock owned by MPM.

·                  HCV, beneficial owner of 14.39% of the Common
Stock, has the right to designate a nominee for director on the Company’s board
of directors (the “Board”) as required by the Note and Warrant Purchase
Agreement.  Dr. James Cavanaugh, a
director of the Company, is a general partner of the general partner of HCV.

·                  Mary Pappajohn, the spouse of John Pappajohn,
the chairman of the Company’s Board.

·                  Derace Schaffer, director.

·                  Joel McCleary, director.

·                  David Wright, CEO and director.

·                  Eric Richman, Senior VP, Business Development
and Strategic Planning.

·                  Christopher Camut, CFO at the time of the
Financing and currently Vice President, Government Contracts and Special
Projects.

The Notes and Warrants were issued pursuant to the
exemption from registration provided by Section 4(2) of the
Securities Act of 1933, as amended (the “Act”) and Regulation D promulgated
thereunder.  In the Note and Warrant
Purchase Agreement, the Investors made representations and warranties regarding
their investment intent, including, among others, representations that they
were purchasing their securities for their own accounts, for investment
purposes and not with a view to distribution or resale of the securities except
in full compliance with all applicable provisions of the Act.  In addition, each of the Investors
represented that it had made its own independent decision to purchase
securities in the Financing.

(2) The Notes purchased by Baker
Brothers, if fully converted within 60 days of August 25, 2009 (the date as of
which information was provided in the Registration Statement) would amount to
approximately 11.7% of the Company’s outstanding Common Stock.  However, as disclosed in the Registration
Statement, the Notes and Warrants issued to Baker Brothers provide that such
Notes and Warrants are only convertible or exercisable to the extent that the
holders thereof and their affiliates would beneficially own no more than 9.999%
of the outstanding shares of Common Stock after such conversion or exercise and
that such limitations on conversion and exercise may not be waived.  In light of these provisions (and the fact
that Baker Brothers does not have any board representation), the Company does
not deem Baker Brothers to be an Affiliate.

6

As disclosed in the Company’s definitive proxy
statement filed with the Commission on September 29, 2009, as of September 11,
2009, the Company had an aggregate of 28,427,348 shares of Common Stock
outstanding.  Of the number of shares of
Common Stock outstanding, 13,747,978 shares, representing the “public float”,
were held by non-affiliates of the Company.
The number of shares outstanding on a fully diluted basis, i.e.,
assuming conversion or exercise of all outstanding notes, warrants or options
convertible or exercisable into Common Stock, was 47,528,366.

On August 31, 2009, the Company

Mail Stop 4720       September 17, 2009
Via Facsimile and U.S. Mail

David P. Wright Chief Executive Officer PharmAthene, Inc. One Park Place, Suite 450 Annapolis, Maryland 21401
 Re: PharmAthene, Inc.
  Amendment No. 1 to Registra tion Statement on Form S-3
  Filed August 31, 2009
  File No. 333-161587

Dear Mr. Wright:
This is to advise you that we  have limited our review of the above information statement
to the issues identified below.  We will make no further review of this filing.
Where indicated, we think you should revise  your document in response to these
comments.  If you disagree, we will consider your explanation as to why our comment is
inapplicable or a revision is unnecessary.  Please be as detailed as necess ary in your explanation.
After reviewing this information, we ma y or may not raise additional comments.
 Please understand that the purpose of our re view process is to assist you in your
compliance with the applicable disclosure requir ements and to enhance the overall disclosure in
your filing. We look forward to working with you in these respects. We welcome any questions
you may have about our comments or on any other as pect of our review. Feel free to call us at
the telephone numbers listed at the end of this letter.
 General

1. We note that you are registering the sale of 11,704,010 common shares. Given the size relative to the number of shares outstan ding held by non-affiliates, the nature of
the offering and the selling security holders , the transaction app ears to be a primary
offering. Because you are not eligible to conduct a primary offering on Form S-3 you
are not eligible to conduct a primary at-t he-market offering under Rule 415(a)(4).

David P. Wright
PharmAthene, Inc. September 17, 2009
Page 2
If you disagree with our analysis, please a dvise the staff of the company’s basis for
determining that the transaction is appropriately characterized as a transaction that is eligible to be made under Rule 415(a)(1)(i) .  In your analysis, please address the
following among any other relevant factors:

• The date on which and the manner in which each selling shareholder received the shares and/or the overlying securities;

• The relationship of each selling shareholder with the company, including an
analysis of whether the selling sharehol der is an affiliate of the company;

• Any relationships among th e selling shareholders;

• The dollar value of the shares registered in relation to the proceeds that the company received from the selling share holders for the securities, excluding
amounts of proceeds that were returned (or will be returned) to the selling
shareholders and/or their affiliates in fees or other payments;

• The discount at which the shareholders will purchase the common stock underlying the convertible notes (or any re lated security, such as a warrant or
option) upon conversion or exercise; and

• Whether or not any of the selling shareholders is in the business of buying and selling securities.

2. Please provide us, with a view toward disc losure in the prospectus, with the total
dollar value of the securitie s underlying the c onvertible notes and warrants that you
have registered for resale (using the number of underl ying securities that you have
registered for resale and the market price per share for those secu rities on the date of
the sale of the convertib le notes and warrants).

3. Please provide us, with a view toward disc losure in the prospectus, with tabular
disclosure of the dollar amount of each paym ent (including the value of any payments
to be made in common stock) in connecti on with the transaction that you have made
or may be required to make to any selling shareholder, any affiliate of a selling shareholder, or any person with whom any selling shareholder has a contractual relationship regarding the tr ansaction (including any interest payments, liquidated
damages, payments made to “finders” or “placement agents,” and any other payments or potential payments).  Please provide foot note disclosure of the terms of each such
payment.  Please do not include any repaymen t of principal on the convertible notes
in this disclosure.

Further, please provide us, with a view to ward disclosure in the prospectus, with
disclosure of the net proceeds to the issuer from the sale of the convertible notes and

David P. Wright
PharmAthene, Inc. September 17, 2009
Page 3
warrants and the total possible payments to all selling shareholders and any of their
affiliates in the first year following the sale of convertible notes.

4. Please provide us, with a view toward disc losure in the prospectus, with tabular
disclosure of:

• the total possible profit the selling share holders could realize as a result of the
conversion discount for the securitie s underlying the convertible notes,
presented in a table with the following  information disclosed separately:

o the market price per share of  the securities underlying the
convertible notes on the date of the sale of the convertible notes;

o the conversion price per share of  the underlying securities on the
date of the sale of the convertible notes, calculated as follows:

ƒ if the conversion price per share is set at a fixed price, use
the price per share established in the convertible notes; and

ƒ if the conversion price per shar e is not set at a fixed price
and, instead, is set at a floating rate in relationship to the market price of the underlying security, use the conversion
discount rate and the market ra te per share on the date of
the sale of the convertible  notes and determine the
conversion price per share as of that date;

• the total possible shares underlying the c onvertible notes (assuming no interest
payments and complete conversion th roughout the term of the notes);

• the combined market price of the total number of shares underlying the
convertible notes, calculated by using the market price per share on the date of
the sale of the convertible notes and the total possible shares underlying the
convertible notes;

• the total possible shares the selling shareholders may receive and the
combined conversion price of the to tal number of shares underlying the
convertible notes calculated  by using the conversion price on the date of the
sale of the convertible no tes and the total possible num ber of shares the selling
shareholders may receive; and

• the total possible discount to  the market price as of th e date of the sale of the
convertible notes, calculated by subtr acting the total conversion price on the
date of the sale of the convertible note s from the combined market price of the
total number of shares underlying th e convertible notes on that date.

David P. Wright
PharmAthene, Inc. September 17, 2009
Page 4
If there are provisions in th e convertible notes that coul d result in a change in the
price per share upon the occurrence of cer tain events, please provide additional
tabular disclosure as appropriate.  For exam ple, if the conversion price per share is
fixed unless and until the market price falls below a stated price, at which point the
conversion price per share drops to a lower price, please provide additional
disclosure.

5. Please provide us, with a view toward disclosure in the prospectus, with tabular
disclosure of:

• the total possible profit to be realized as a result of  any conversion discounts
for securities underlying any other warrants, options, notes, or other securities of the issuer that are held by the selling shareholders or any affiliates of the selling shareholders, presented in a table with the following information
disclosed separately:

o market price per share of the unde rlying securities on the date of
the sale of that other security;

o the conversion/exercise price per shar e as of the date of the sale of
that other security, cal culated as follows:

ƒ if the conversion/exercise pric e per share is set at a fixed
price, use the price per share on the date of the sale of that
other security; and

ƒ if the conversion/exercise pric e per share is not set at a
fixed price and, instead, is set at a floating rate in
relationship to the market pr ice of the underlying security,
use the conversion/exercise di scount rate and the market
rate per share on the date of th e sale of that other security
and determine the conversion price per share as of that date;

• the total possible shares  to be received under the particular securities
(assuming complete conversion/exercise);

• the combined market price of th e total number of underlying shares,
calculated by using the market price per sh are on the date of the sale of that
other security and the total possible shares to be received;

• the total possible shares to  be received and the comb ined conversion price of
the total number of shares underlying th at other security calculated by using
the conversion price on the date  of the sale of that ot her security and the total
possible number of underlying shares; and

David P. Wright
PharmAthene, Inc. September 17, 2009
Page 5
• the total possible discount to the market price as of the date of the sale of that
other security, calculated by subtracting the total conversion/exercise price on
the date of the sale of that other secu rity from the combined market price of
the total number of underly ing shares on that date.

6. Please provide us, with a view toward disclosure in the prospectus, with tabular
disclosure of:

• the gross proceeds paid or payable to  the issuer in the convertible note
transaction;

• all payments that have been made or that may be required to be made by the
issuer that are disclosed in response to Comment 3 above;

• the resulting net proceeds to the issuer; and

• the combined total possible profit to be realized as a result of any conversion
discounts regarding the secu rities underlying the c onvertible notes and any
other warrants, options, notes, or other s ecurities of the issuer that are held by
the selling shareholders or any affiliates of the sell ing shareholders that is
disclosed in response to Comm ent 4 and Comment 5 above.

Further, please provide us, with a view to ward disclosure in the prospectus, with
disclosure – as a percentage – of the total amount of all possible payments as
disclosed in response to Comment 3 and th e total possible discount to the market
price of the shares underlyi ng the convertible note as disclosed in response to
Comment 4 divided by the net proceeds to the issuer from the sale of the convertible
notes, as well as the amount of that resulting percentage averaged over the term of the
convertible notes.

7. Please provide us, with a view toward disclosure in the prospectus, with tabular
disclosure of all prior securities transact ions between the issuer (or any of its
predecessors) and the selling shareholders, any affiliates of the selling shareholders,
or any person with whom any selling shareholder has a contractual relationship regarding the transaction (or any predecesso rs of those persons), with the table
including the following information disclo sed separately for each transaction:

• the date of the transaction;

• the number of shares of the class of secu rities subject to the transaction that
were outstanding prior to the transaction;

• the number of shares of the class of secu rities subject to the transaction that
were outstanding prior to the transacti on and held by persons other than the

David P. Wright
PharmAthene, Inc. September 17, 2009
Page 6
selling shareholders, affiliates of th e company, or affiliates of the selling
shareholders;

• the number of shares of the class of secu rities subject to the transaction that
were issued or issuable in connection with the transaction;

• the percentage of total is sued and outstanding securiti es that were issued or
issuable in the transaction (assuming full issuance), with the percentage
calculated by taking the number of shar es issued and outstanding prior to the
applicable transaction and held by persons other than the selling shareholders,
affiliates of the company, or affiliates of the selling shareholders, and dividing
that number by the number of shares issued  or issuable in connection with the
applicable transaction;

• the market price per share of the class of  securities subject to the transaction
immediately prior to the tran saction (reverse split adju sted, if necessary); and

• the current market price per share of the class of securities subject to the
transaction (reverse split adjusted, if necessary).

8. Please provide us, with a view toward disclosure in the prospectus, with tabular
disclosure comparing:

• the number of shares outstanding prior to the convertible note transaction that
are held by persons other than the se lling shareholders, affiliates of the
company, and affiliates of the selling shareholders;

• the number of shares registered for re sale by the selling shareholders or
affiliates of the selling shareholders in prior registration statements;

• the number of shares registered for re sale by the selling shareholders or
affiliates of the selling shareholders that continue to be held by the selling
shareholders or affiliates of the selling shareholders;

• the number of shares that have been sold in registered resa le transactions by
the selling shareholders or affiliates of the selling shareholders; and

• the number of shares registered for resale  on behalf of the selling shareholders
or affiliates of the selling sharehol ders in the current transaction.
 In this analysis, the calculation of the number of outstanding shares should not
include any securities underl ying any outstanding convertib le securities, options, or
warrants.

David P. Wright
PharmAthene, Inc. September 17, 2009
Page 7
9. Please provide us, with a view toward disclosure in the prospectus , with the following
information:

• whether the issuer has the intention, and a reasonable basis to believe that it
will have the financial ability, to make all payments on the overlying securities; and

• whether – based on information obtained from the selling shareholders – any
of the selling shareholders have an existing short position in the company’s
common stock and, if any of the selling shareholders have an existing short
position in the company’s stock, the following additional information:

o the date on which each such selli ng shareholder entered into that
short position; and
 o the relationship of the date on which each such selling shareholder entered into that short position to the date of th e announcement of
the convertible note transaction a nd the filing of the registration
statement ( e.g., before or after the announ cement of the convertible
note transaction, before the fili ng or after the filing of the
registration statement, etc.).

10. Please provide us, with a view toward disclosure in the prospectus, with:

• a materially complete description of the relationships and arrangements that
have existed in the past three years or  are to be performed in the future
between the issuer (or any of its predecessors) and the selling shareholders,
any affiliates of the selling shareholders , or any person with whom any selling
shareholder has a contractual relationsh ip regarding the transaction (or any
predecessors of those persons) – the in formation provided should include, in
reasonable detail, a complete descripti on of the rights and obligations of the
parties in connection with the sale of the convertible notes; and

• copies of all agreements between the issuer (or any of its predecessors) and
the selling shareholders, any affiliates of the selling shareholders, or any person with whom any selling share holder has a contractual relationship
regarding the transaction (or any predece ssors of those persons) in connection
with the sale of the convertible notes.

If it is your view th at such a description of the relationships and arrangements
between and among those parties already

Mail Stop 6010         May 15, 2008  Mr. Christopher C. Camut Chief Financial Officer and Secretary PharmAthene, Inc. One Park Place, Suite 450 Annapolis, MD 21401
Re: PharmAthene, Inc.
  Preliminary Proxy Statement on Schedule 14A
  Filed on April 29, 2008   File Number 001-32587
Dear Mr. Camut:

We have completed our review of your proxy statement and have no further comments at
this time.  Please contact Sonia Barros at (202) 551-3655 with any questions.         S i n c e r e l y ,            J e f f r e y  R i e d l e r         A s s i s t a n t  D i r e c t o r   cc: Jeffrey A. Baumel, Esq.
Sonnenschein Nath & Rosenthal LLP 101 JFK Parkway Short Hills, NJ 07078

CORRESP
1
filename1.htm

Michele  Vaillant

Partner

T.
973.639.2011

F.
973.297.3826

mvaillant@mccarter.com

McCarter &
English, LLP

Four
Gateway Center

100
Mulberry Street

Newark,
NJ  07102

T.
973.622.4444

F.
973.624.7070

www.mccarter.com

May 7, 2008

VIA EDGAR

United States Securities and Exchange Commission

Office of Emerging Growth Companies

100 F Street, NE - Mail Stop 6010

Washington, D.C. 20549

  Attn: Mr. Jeffrey Riedler

  Ms. Sonia Barros

  Re:

  PharmAthene, Inc.

  Preliminary Proxy Statement on Schedule 14A

  Filed on April 29, 2008

  File No. 001-32587

Dear Sir and Madam:

On behalf of PharmAthene, Inc. (the “Company”), we hereby submit
the Company’s response to the Staff’s comment contained in the letter, dated May 2,
2008, from Jeffrey Riedler.  For
convenience, the comment is set forth below followed by the Company’s response.

Proxy Card

1.  Please provide for a mechanism enabling a
noteholder to vote for some nominees for director and vote against other
nominees for director.  See Rule 14a-4(b)(2).

The Noteholder Proxy Card has
been revised to provide a mechanism enabling a Noteholder to vote for some
nominees for director and vote against other nominees for director in
accordance with Rule 14a-4(b)(2).  A
clean and a marked version of the revised Noteholder Proxy Card are provided
together with this letter for consideration.
The Company’s representation letter is also provided.

Please contact the undersigned at 973-639-2011 to discuss any further
comments in this regard.  Thank you.

  Very truly
  yours.

  /s/ Michele
  F. Vaillant

  Michele F.
  Vaillant

cc:  David P. Wright, President

         and
CEO

PHARMATHENE, INC.

ANNUAL
MEETING OF STOCKHOLDERS

Friday, June 13,
2008

10:00 a.m. New York Time

THE BEAR
STEARNS COMPANIES, INC.

383 Madison Avenue

New York,
NY 10179

8% Convertible Notes issued August 3, 2007

  PharmAthene, Inc.

  One Park Place, Suite 450

  Annapolis, MD 21401

  proxy

For The
Annual Meeting To Be Held June 13, 2008

The undersigned hereby constitutes and appoints John
Pappajohn and David P. Wright, and each of them, attorneys and agents, with
full power of substitution, to vote as proxy all 8% Convertible Notes issued August 3,
2007 of PharmAthene, Inc.(the “Company”) standing in the name of the
undersigned at the Annual Meeting of Stockholders of the Company to be held at
the offices of The Bear Stearns Companies, Inc. located at 383 Madison
Avenue, New York, New York 10179 at 10:00 a.m., New York time, on Friday, June 13,
2008, and at any adjournment or postponement thereof, in accordance with the
instructions noted below, and with discretionary authority with respect to such
other matters as may properly come before such meeting or any adjournment or
postponement thereof. Receipt of notice of such meeting and the Proxy Statement
therefor dated May   , 2008 is hereby acknowledged.

This Proxy will be voted in
accordance with the Noteholder’s specifications hereon. In the absence of any
such specification, this Proxy will be voted:

  ·

  “FOR” James H. Cavanaugh, Ph.D.,
  Elizabeth Czerepak and Steven St. Peter as Directors of the Company.

The undersigned hereby revokes any
proxies heretofore given and directs said attorneys to act or vote as follows:

  1. Election of directors:

  01
  James H. Cavanaugh, Ph.D.

  02
  Elizabeth Czerepak

  o

  Vote
  FOR all

  nominees

  o

  Vote
  WITHHOLD

  AUTHORITY to vote

  03
  Steven St. Peter

  listed
  (except as marked)

   for all nominees

  listed

  FOR all nominees listed, except
  that authority to vote withheld for the following nominee(s): Write the
  number(s) of the nominee(s) in the box provided to the right.

  1. Proposal to elect James H. Cavanaugh,
  Ph.D., Elizabeth Czerepak and Steven St. Peter  to the Board of Directors of the Company.

  o

  For

  o

  Against

THIS PROXY IS SOLICITED ON BEHALF
OF THE HOLDERS OF THE COMPANY’S 8% CONVERTIBLE NOTES ISSUED AUGUST 3, 2007

  SIGN HERE EXACTLY AS NAME(S) APPEAR(S) ON
  THE CARD

  Date

  Signature(s)

  NOTE: When shares are held by joint tenants, both should sign. When
  signing as attorney, trustee, administrator, executor, guardian, etc., please
  indicate your full title as such. If a corporation, please sign in full
  corporate name by President or other authorized officer. If a partnership,
  please sign in full partnership name by authorized person.

  Please complete and date this proxy and return it
  promptly

  in the enclosed postage-prepaid envelope.

PHARMATHENE,
INC.

ANNUAL
MEETING OF STOCKHOLDERS

Friday, June 13,
2008

10:00 a.m.
New York Time

THE BEAR
STEARNS COMPANIES, INC.

383 Madison
Avenue

New York,
NY 10179

8% Convertible Notes issued August 3, 2007

  PharmAthene, Inc.

  One Park Place, Suite 450

  Annapolis, MD 21401

  proxy

For The
Annual Meeting To Be Held June 13, 2008

The undersigned hereby constitutes and appoints John
Pappajohn and David P. Wright, and each of them, attorneys and agents, with
full power of substitution, to vote as proxy all 8% Convertible Notes issued August 3,
2007 of PharmAthene, Inc.(the “Company”)
standing in the name of the undersigned at the Annual Meeting of Stockholders
of the Company to be held at the offices of The Bear Stearns Companies, Inc.
located at 383 Madison Avenue, New York, New York 10179 at 10:00 a.m., New
York time, on Friday, June 13, 2008, and at any adjournment or
postponement thereof, in accordance with the instructions noted below, and with
discretionary authority with respect to such other matters as may properly come
before such meeting or any adjournment or postponement thereof. Receipt of
notice of such meeting and the Proxy Statement therefor dated May     ,
2008 is hereby acknowledged.

This Proxy will be voted in accordance with the Noteholder’s
specifications hereon. In the absence of any such specification, this Proxy
will be voted:

  ·

  “FOR” James H. Cavanaugh, Ph.D., Elizabeth Czerepak
  and Steven St. Peter as Directors of the Company.

The undersigned hereby revokes any
proxies heretofore given and directs said attorneys to act or vote as follows:

  1. Election
  of directors:

  01 James H. Cavanaugh, Ph.D.

  03 Steven St. Peter

  02 Elizabeth Czerepak

  o

  Vote FOR all nominees listed (except as marked)

  o

  Vote WITHHOLD AUTHORITY to vote for all nominees

  listed

  FOR all nominees listed, except that authority to
  vote withheld for the following nominee(s): Write the number(s) of the
  nominee(s) in the box provided to the right.

THIS PROXY IS SOLICITED ON BEHALF OF THE HOLDERS OF
THE COMPANY’S 8% CONVERTIBLE NOTES ISSUED AUGUST 3, 2007

  SIGN HERE EXACTLY AS NAME(S) APPEAR(S) ON THE CARD

  Date

  Signature(s)

  NOTE: When shares are held by joint tenants, both should sign. When
  signing as attorney, trustee, administrator, executor, guardian, etc., please
  indicate your full title as such. If a corporation, please sign in full
  corporate name by President or other authorized officer. If a partnership,
  please sign in full partnership name by authorized person.

Please complete
and date this proxy and return it promptly

in the
enclosed postage-prepaid envelope.

PharmAthene, Inc.

One Park Place, Suite 450

Annapolis, Maryland  21401

May 5, 2008

VIA EDGAR

United States Securities and Exchange Commission

Office of Emerging Growth Companies

100 F Street, NE - Mail Stop 6010

Washington, D.C. 20549

Attn:            Mr. Jeffrey
Reidler

Ms. Sonia Barros

  Re:

  PharmAthene, Inc.

  Preliminary Proxy Statement

  Filed on April 29, 2008

  File No. 1-32587

Dear Sir and Madam:

Pursuant to the letter from the Staff, dated May 2, 2008,
PharmAthene, Inc. (the “Company”) acknowledges that:

·                 the Company is
responsible for the adequacy and accuracy of the disclosure in the filing;

·                 Staff comments or
changes to disclosure in response to staff comments do not foreclose the
Commission from taking any action with. respect to the filing; and

·                 the Company may
not assert Staff comments as a defense in any proceeding initiated by the
Commission or any person under the federal securities laws of the United
States.

In addition, we understand and acknowledgement that that the Division
of Enforcement has access to all information which we have provided to the
Staff of the Division of Corporation Finance in its review of our filing or in
response to SEC comments on our filing.

  Sincerely,

  PharmAthene, Inc.

  By:

  /s/David P. Wright

  David P. Wright

  President and Chief Executive Officer

Mail Stop 6010         May 2, 2008  Mr. Christopher C. Camut Chief Financial Officer and Secretary PharmAthene, Inc. One Park Place, Suite 450 Annapolis, MD 21401
Re: PharmAthene, Inc.
  Preliminary Proxy Statement on Schedule 14A
  Filed on April 29, 2008   File Number 001-32587
Dear Mr. Camut:

This is to advise you that we have limited our review of the above proxy statement to the
issues identified below.  We will make no further review of this filing.
Where indicated, we think you should revise your documents in response to these
comments.  If you disagree, we will consider your explanation as to why our comment is inapplicable or a revision is unnecessary.  Please be as detailed as necessary in your explanation.  In some of our comments, we may ask you to provide us with supplemental information so we may better understand your disclosure.  After reviewing this information, we may or may not raise additional comments.  Proxy Card

1. Please provide for a mechanism enabling a noteholder to vote for some nominees for director and vote against other nominees for director.  See Rule 14a-4(b)(2).
   As appropriate, please revise your proxy statement in response to this comment.  You may wish to provide us with marked copies of the revised document to expedite our review.  Please furnish a response letter that keys your responses to our comments.  Detailed cover letters greatly facilitate our review.  Please file your cover letter on EDGAR under the form type label CORRESP.  Please understand that we may have additional comments after reviewing your amendment and responses to our comments.

Mr. Christopher C. Camut
PharmAthene, Inc. May 2, 2008 Page 2   We urge all persons who are responsible for the accuracy and adequacy of the disclosure in the filings reviewed by the staff to be certain that they have provided all information investors require.  Since the company and its management are in possession of all facts relating to a company`s disclosure, they are responsible for the accuracy and adequacy of the disclosures they have made.   In connection with responding to our comments, please provide, in writing, a statement from the company acknowledging that
• the company is responsible for the adequacy and accuracy of the disclosure in the filings;

• staff comments or changes to disclosure in response to staff comments in the filings reviewed by the staff do not foreclose the Commission from taking any action with respect to the filing; and

• the company may not assert staff comments as a defense in any proceeding initiated by the Commission or any person under the federal securities laws of the United States.
  In addition, please be advised that the Division of Enforcement has access to all information you provide to the staff of the Division of Corporation Finance in our review of your filing or in response to our comments on your filing.
Please contact Sonia Barros at (202) 551-3655 with any questions.
        S i n c e r e l y ,            J e f f r e y  R i e d l e r         A s s i s t a n t  D i r e c t o r  cc:  Jeffrey A. Baumel, Esq.
McCarter & English, LLP  Four Gateway Center  100 Mulberry Street  Newark, NJ 07102

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549-7010

       DIVISION OF
CORPORATION FINANCE

Mail Stop 3561  July 13, 2007

Mr. John Pappajohn, Chairman of the Board Healthcare Acquisition Corp 2116 Financial Center 666 Walnut Street Des Moines, Iowa 50309
 Re: Healthcare Acquisition Corp
  Preliminary Proxy Statement   Filed on July 13, 2007   File No. 1-32587

Dear Mr. Pappajohn:
We have reviewed your filing and have the following comments.  Where
indicated, we think you should revise your document in response to these comments.  If you disagree, we will consider your explanation as to why our comment is inapplicable or a revision is unnecessary.  Please be as detailed as necessary in your explanation.  In some of our comments, we may ask you to provide us with supplemental information so we may better understand your disclosure.  After reviewing this information, we may or may not raise additional comments.
Please understand that the purpose of our review process is to assist you in your
compliance with the applicable disclosure requirements and to enhance the overall disclosure in your filing.  We look forward to working with you in these respects.  We welcome any questions you may have about our  comments or on any other aspect of our
review.  Feel free to call us at the telephone numbers listed at the end of this letter.  Future Cash Needs, page 112

1. Please briefly indicate the basis for the belief that PharmAthene will be the
recipient of all future grant funds to be received from the United States Government.
 Collaborations, page 122

2. We note the disclosure concerning your relationship with Medarex.  Please
revise to indicate the amount of the milestone payment PharmAthene is required to make to achieve a 50% profit share in the collaboration agreement.
General

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp July 13, 2007 Page 2

As appropriate, please amend your proxy statement in response to these
comments.  You may wish to provide us with marked copies of the amendment to expedite our review.  Please furnish a cover letter with your amendment that keys your responses to our comments and provides any requested supplemental information.  Detailed cover letters greatly facilitate our review.  Please understand that we may have additional comments after reviewing your amendment and responses to our comments.

  We urge all persons who are responsible for the accuracy and adequacy of the disclosure in the filing to be certain that the filing includes all information required under the Securities Exchange Act of 1934 and that they have provided all information investors require for an informed investment decision.  Since the company and its management are in possession of all facts relating to a company’s disclosure, they are responsible for the accuracy and adequacy of the disclosures they have made.     You may contact David Walz at (202)  551-3358 if you have questions regarding
comments on the financial statements and related matters.  Please contact Duc Dang at (202) 551-3386 or David Link, who supervised the review of your filing, at (202) 551-
3790 with any other questions.
Sincerely,

John Reynolds, Assistant Director Office of Emerging Growth Companies
  cc:  Brian Daughney        (212) 370-7889

CORRESP
1
filename1.htm

      Unassociated Document

    Healthcare
      Acquisition Corp

    2116
      Financial Center

    666
      Walnut Street

    Des
      Moines, Iowa 50309

    July
      13,
      2007

    VIA
      EDGAR

    United
      States Securities and Exchange Commission

    Office
      of
      Emerging Growth Companies

    100
      F
      Street, NE - Mail Stop 3561

    Washington,
      D.C. 20549

    Attn: Mr.
      Duc
      Dang

              Re:

              Healthcare
                Acquisition Corp

    Preliminary
      Proxy Statement Amendment No. 4

    Filed
      on July 12, 2007

    File
      No. 1-32587

    Mr.
      Dang:

    Pursuant
      to the comment letter from the Staff dated July 11, 2007, Healthcare Acquisition
      Corp. (the “Company”) acknowledges that:

              ·

              the
                Company is responsible for the adequacy and accuracy of the disclosure
                in
                the filing;

              ·

              staff
                comments or changes to disclosure in response to staff comments do
                not
                foreclose the Commission from taking any action with. respect to
                the
                filing; and

              ·

              the
                Company may not assert staff comments as a defense in any proceeding
                initiated by the Commission or any person under the federal securities
                laws of the United States.

    In
      addition, we understand and acknowledgement that that the Division of
      Enforcement has access to all information which we have provided to the staff
      of
      the Division of Corporation Finance in its review of our filing or in response
      to SEC comments on our filing.

              Sincerely,

              Healthcare
                Acquisition Corp.

              By:/S/
                Matthew
                Kinley

              Matthew
                Kinley

              President

CORRESP
1
filename1.htm

    Ellenoff
      Grossman & Schole LLP

    370
      Lexington Avenue - 19th
      Floor

    New
      York, New York 10017

    Tel.
      No.: 212-370-1300

    Fax
      No.: 212-370-7889

    July
      12,
      2007

    VIA
      EDGAR

    Mr.
      John
      Pappajohn, Chairman of the Board

    Healthcare
      Acquisition Corp

    2116
      Financial Center

    666
      Walnut Street

    Des
      Moines, Iowa 50309

              Re:

              Healthcare
                Acquisition Corp

    Preliminary
      Proxy Statement Amendment No. 3

    Filed
      on June 29, 2007

    File
      No. 1-32587

    Ladies
      and Gentlemen:

    On
      behalf
      of Healthcare Acquisition Corp. (the “Company”
or
      “HAQ”)
      we are
      submitting our response to the Staff’s comments in a letter from John Reynolds,
      Assistant Director, dated July 11, 2007 addressed to John Pappajohn, Chairman
      of
      the Board of the Company. Set forth below is the actual Staff comment and
      our  response.

    As
      we
      have indicated in our telephone conversations with the Staff, we appreciate
      any
      assistance that the Staff can provide to complete this review. As we have
      previously advised, HAQ must complete the acquisition before August 3, 2007
      or
      it will be required to liquidate. We must provide at least 10 days notice
      to stockholders of the meeting, and given the time necessary to print the
      proxy statement and mail, we must clear the review process by mid-morning on
      Friday in order to hold our meeting date on July 27th. We have also attached
      the
      actual pages which have changed in accordance with our responses below to assist
      you in your review.

    General

              1.

              We
                note your response to comments seven and eight of our letter dated
                June
                26, 2007 and the additional disclosure on pages 66 and 68. The additional
                disclosure states that your management believes that the revenue
                projections provided by PharmAthene were prepared using similar criteria
                and methods considered by research analyst. Please revise to clarify
                the
                basis and confirm if the companies with drugs not yet marketable
                also rely
                on estimates of possible sales to SNS.

    We
      have
      revised the disclosure as requested. Specifically, we have added language
      at page 66 of the Proxy Statement to include the following
      statements:

    Management
      of HAQ reviewed several publicly available research reports prepared by third
      party analysts regarding the peer group companies and compared the criteria
      utilized in these reports to the criteria utilized by PharmAthene in its
      projections. At least two of the reports included discussions of estimates
      related to potential revenues of the peer group companies for product
      undertakings in the bio defense arena for their products to U.S. government
      agencies, including the United States Strategic National Stockpile. The analyst
      reports contained summaries of the businesses of the peer group
      companies, and their significant products under development,
      projections for existing and future products, potential grants and research
      contracts, pending research and development projects, potential financial
      milestones and related materials. HAQ’s management determined that the criteria
      utilized by PharmAthene in preparing its projections were similar to those
      considered by third party industry analysts for publicly traded companies within
      the peer group.

    As
      supplemental information in response to the Staff’s comment, we advise the Staff
      HAQ’s management reviewed the following research reports:

                ·

                a
                  research report on SIGA Technologies, Inc. dated November 22, 2006
                  prepared by Advent Financial;

                ·

                a
                  research report on Avi BioPharma, Inc. dated November 16, 2006
                  prepared by
                  Rodmen & Renshaw;

                ·

                two
                  research reports on BioCryst Pharmaceuticals dated February 17,
                  2006 and
                  August 10, 2006, respectively, prepared by C. E. Unterberg, Towbin
                  and
                  Rodman and Renshaw, respectively;
                  and

                ·

                a
                  research report on AVI BioPharma, Inc. dated August 9, 2006, prepared
                  by
                  Rodman and Renshaw.

              2.

              In
                connection with the preceding comment, please revise to clarify if
                you
                received any direct indication from SNS that they would purchase
                your
                products.

    We
      have
      revised the disclosure as requested. Specifically, we have added additional
      language at page 70 of the Proxy Statement to include the following
      statement:

    Although
      management of PharmAthene has engaged in discussions with the Department of
      Homeland Security and the Department of Health and Human Services regarding
      its
      products and their potential efficacy in addressing national bioterrorism
      concerns, PharmAthene has not received any definitive indications or statements
      or commitments from the SNS that it will make purchases from PharmAthene.

              3.

              We
                note the additional disclosure on page 69 in response to comment
                12 of our
                letter dated June 26, 2007. Please revise to clarify how you “tempered
                such consideration” because of the different rights and abilities of the
                private investors versus common stock holders. In that regard, reconcile
                the “tempering” with the fact that the target based the share price on the
                price of the preferred securities.

      We
        have revised the disclosure as requested. Specifically, we have added additional
        language at pages 71 to 72 to include the following
        statements:

    HAQ’s
      management
      recognized that although holders of preferred stock may allocate a greater
      value
      to preferred shares than common shares because of certain of their control
      provisions, they also recognized that such advantages generally are more
      important in allocating relative value among equity holders rather than as
      a
      factor in adjusting total valuation for a company. In addition, at the time
      of
      the Series C financing, the holders of Preferred Stock held more than 86% of
      the
      total as converted capitalization of PharmAthene, so that the relative
      preferential value that might ordinarily be ascribed to preferred stock is
      not
      as relevant in PharmAthene’s case. Therefore, HAQ’s Board believed that the
      valuation of PharmAthene established by the preferred stockholders provided
      a
      fair basis for evaluating valuation.

    We
      have
      also removed the word “tempering” and replaced it with “balancing”.

              4.

              We
                note the proposed disclosure concerning your relationship with Medarex.
                What you have disclosed does not appear to discuss the principal
                and
                material terms of the agreement. Please revise to disclose
                all
                material terms of your agreement with Medarex. Specifically address
                how
                profits will be shared with Medarex or provide us with an analysis
                why
                this information is not material to an investor. Please revise
                accordingly.

    In
      response to Staff's comment we have added to the discussion at pages 122 to
      123
      of the Proxy Statement disclosure of the material terms of the agreement with
      Medarex.

      PharmAthene
        entered into a collaboration agreement with Medarex in November 2004 to
        co-develop Valortim(tm) as a therapeutic for individuals infected with anthrax
        as well as for prophylactic treatment of individuals exposed to anthrax.
        In
        2004, under the terms of the collaboration agreement, Medarex received an
        initial payment of two million dollars ($2,000,000) from PharmAthene to fund
        planned development activities. Under the collaboration agreement, PharmAthene
        is responsible for funding all research and development and commercialization
        activities that exceed current and future government funding. The collaboration
        agreement provides that Medarex and PharmAthene will share operating profits
        according to a formula such that PharmAthene’s share of the operating profits
        could increase from an initial level of 20% to as high as 60% generally as
        follows: (i) upon execution of the collaboration agreement and the $2 million
        initial payment, PharmAthene’s profit share was 20%; (ii) in order to maintain
        its 20% profit share PharmAthene is required to contribute funding in an
        amount
        equivalent to the funding provided by the U.S. Government to Medarex via
        grants
        awarded to fund Valortim(tm) development work (approximately $7.2 million);
        (iii) PharmAthene’s share of operating profits will increase to 50% if a
        contract for the procurement of Valortim(tm) is entered into with the U.S.
        Government and PharmAthene has satisfied its obligation under (ii) above;
        and
        (iv) PharmAthene’s share of the operating profits can increase by 10% for every
        $5 million of funding provided by PharmAthene over and above the initial
        payment
        of $2 million and the amount that it provides as funding in excess of the
        matching by PharmAthene of funds provided to Medarex under (ii) above.
        PharmAthene’s aggregate share of the operating profits is capped at 50% if the
        condition under (iii) is not satisfied and 60% if it is satisfied. Should
        the
        parties enter into a contract for the procurement of Valortim(tm) with the
        U.S.
        Government prior to PharmAthene satisfying its obligation under (ii) above,
        PharmAthene is required to make a milestone payment to Medarex in order to
        achieve a 50% profit share in the program. Prior to distribution of operating
        profits, each party is entitled to reimbursement of research and development
        expenses incurred that were not otherwise covered by government
        funding

              5.

              Also
                in connection with your proposed revisions, clarify how you will
                obtain
                the funds to further the development of Valortim. On page 108 you
                disclose
                that you expect grants to fund the remaining development of Valortim™.
                Will those grants be received by you or Medarex? It would appear
                that
                grants received by Medarex would not aid in your ability to receive
                revenues from the sale of Valortim™.

    We
      have
      modified the language appearing at page 108 of the Proxy Statement in response
      to the Staff’s comment.
      It
      appears that a word was missing and together
      with the inserted language now appearing at page 108 we have clarified that
      PharmAthene, not Medarex, will be the recipient of all grant funds and together
      with its credit facility, possible sales of securities and the HAQ trust funds,
      it will have substantial and sufficient funds to develop its
      products.

    If
      you
      have any questions, please contact the undersigned at 212-370-1300, or Matthew
      P. Kinley, the Company’s President, at 515-244-5746.

              Very
                truly yours,

              ELLENOFF
                GROSSMAN & SCHOLE LLP.

              By:
                Brian
                C. Daughney

                Brian C. Daughney

              cc:

              Mr.
                Matthew P. Kinley

              Jeffrey
                Baumel, Esq.

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549-7010

       DIVISION OF
CORPORATION FINANCE

Mail Stop 3561

 July 11, 2007

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
2116 Financial Center
666 Walnut Street
Des Moines, Iowa 50309

 Re: Healthcare Acquisition Corp
  Preliminary Proxy Statement
  Filed on June 29, 2007
  File No. 1-32587

Dear Mr. Pappajohn:

We have reviewed your filing and have the following comments.  Where
indicated, we think you should revise your document in response to these comments.  If
you disagree, we will consider your explanation as to why our comment is inapplicable or a revision is unnecessary.  Please be as detailed as necessary in your explanation.  In some of our comments, we may ask you to provide us with supplemental information so we may better understand your disclosure.  After reviewing this information, we may or may not raise additional comments.

Please understand that the purpose of our review process is to assist you in your
compliance with the applicable disclosure requirements and to enhance the overall disclosure in your filing.  We look forward to working with you in these respects.  We welcome any questions you may have about our comments or on any other aspect of our review.  Feel free to call us at the telephone numbers listed at the end of this letter.

General

1. We note your response to comments seven and eight of our letter dated June 26, 2007 and the additional disclosure on pages 66 and 68.  The additional disclosure states that your management believes that the revenue projections provided by PharmAthene were prepared using similar criteria and methods considered by research analyst.  Please revise to clarify the basis and confirm if the companies with drugs not yet marketable also rely on estimates of possible sales to SNS.

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp July 11, 2007
Page 2

2. In connection with the preceding comment, please revise to clarify if you
received any direct indication from SNS that they would purchase your
products.

3. We note the additional disclosure on page 69 in response to comment 12 of our letter dated June 26, 2007.  Please revise to clarify how you “tempered such consideration” because of the different rights and abilities of the private investors versus common stock holders.  In that regard, reconcile the “tempering” with the fact that the target based the share price on the price of the preferred securities.

4. We note the proposed disclosure concerning your relationship with Medarex.  What you have disclosed does not appear to discuss the principal and material terms of the agreement.  Please revise to disclose
all material terms of your
agreement with Medarex.  Specifically address how profits will be shared with Medarex or provide us with an analysis why this information is not material to an investor.  Please revise accordingly.

5. Also in connection with your proposed revisions, clarify how you will obtain the funds to further the development of Valortim.  On page 108 you disclose that you expect grants to fund the remaining development of Valortim.  Will those grants be received by you or Medarex?  It would appear that grants received by Medarex would not aid in your ability to receive revenues from the sale of Valortim.

General

As appropriate, please amend your proxy statement in response to these
comments.  You may wish to provide us with marked copies of the amendment to expedite our review.  Please furnish a cover letter with your amendment that keys your responses to our comments and provides any requested supplemental information.  Detailed cover letters greatly facilitate our review.  Please understand that we may have additional comments after reviewing your amendment and responses to our comments.

  We urge all persons who are responsible for the accuracy and adequacy of the disclosure in the filing to be certain that the filing includes all information required under the Securities Exchange Act of 1934 and that they have provided all information investors require for an informed investment decision.  Since the company and its management are in possession of all facts relating to a company’s disclosure, they are responsible for the accuracy and adequacy of the disclosures they have made.

 In connection with responding to our comments, please provide, in writing, a statement from the company acknowledging that:

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp July 11, 2007
Page 3

‚ the company is responsible for the adequacy and accuracy of the disclosure in the
filing;

‚ staff comments or changes to disclosure in response to staff comments do not foreclose the Commission from taking any action with respect to the filing; and

‚ the company may not assert staff comments as a defense in any proceeding initiated by the Commission or any person under the federal securities laws of the United States.

In addition, please be advised that the Division of Enforcement has access to all
information you provide to the staff of the Di vision of Corporation Finance in our review
of your filing or in response to our comments on your filing.

You may contact David Walz at (202) 551-3358 if you have questions regarding
comments on the financial statements and related matters.  Please contact Duc Dang at (202) 551-3386 or David Link, who supervised the review of your filing, at (202) 551-
3790 with any other questions.

Sincerely,

John Reynolds, Assistant Director
Office of Emerging Growth Companies

cc:  Brian Daughney
       (212) 370-7889

CORRESP
1
filename1.htm

      Unassociated Document

    Ellenoff
      Grossman & Schole LLP

    370
      Lexington Avenue - 19th
      Floor

    New
      York, New York 10017

    Tel.
      No.: 212-370-1300

    Fax
      No.: 212-370-7889

    July
      10,
      2007

    VIA
      EDGAR

    United
      States Securities and Exchange Commission

    Office
      of
      Emerging Growth Companies

    100
      F
      Street, NE - Mail Stop 3561

    Washington,
      D.C. 20549

    Attn: Mr.
      Duc
      Dang

            Re:

              Healthcare
                Acquisition Corp. Preliminary Proxy Statement on Schedule
                14A

    Filed
      on
      February 9, 2007 as subsequently amended by

    Amendment
      No.1 to Preliminary Proxy Statement on Schedule 14A

    Filed
      April 20, 2007; and

    Amendment
      No. 2 to Preliminary Proxy Statement on Schedule 14A

    Filed
      June 8, 2007

    File
      No.
      001-32587

    Ladies
      and Gentlemen:

    On
      behalf
      of Healthcare Acquisition Corp. (the “Company”
or
      “HAQ”)
      we are
      supplementing our prior response of June 29th
      to the
      Staff’s comments in a letter from John Reynolds, Assistant Director, dated June
      26, 2007 addressed to John Pappajohn, Chairman of the Board of the Company.
      Specifically, we are providing further information related to Staff’s inquiry
      about the Medarex agreement with PharmAthene. Set forth below is the actual
      Staff comment and our supplemental response.

    As
      we
      have indicated in our telephone conversations with the Staff, we appreciate
      any
      assistance that the Staff can provide to complete this review. As we have
      previously advised, HAQ must complete the acquisition before August 3, 2007
      or
      it will be required to liquidate.

    Information
      About PharmAthene, page 111

              1.

              We
                note your response to comment 49 of our letter dated. June 1, 2007
                that
                the agreement you have in place with Medarex is confidential. We
                also note
                that you only have two drugs in production and one of them is in
                partnership with Medarex. As such, it appears that the terms of the
                target’s relationship with Medarex are material to investors’
                understanding of your business going forward. Also, upon consummation
                of
                the merger, material contacts will be filed with the Commission.
                Because
                of the material nature of this relationship, please advise us of
                the basis
                for not disclosing the material terms here.

    We
      would
      propose the following language be inserted into the proxy statement at page
      120:

              Mr.
                Duc Dang

              July
                10, 2008

              Page
                Two

    PharmAthene
      entered into a collaboration agreement with Medarex in November 2004 to
      co-develop Valortim(tm) as a therapeutic for individuals infected with anthrax
      as well as for prophylactic treatment of individuals exposed to anthrax. In
      2004, Medarex received an upfront payment from PharmAthene to fund initial
      development activities. Under the collaboration agreement, PharmAthene is
      responsible for funding all research and development and commercialization
      activities that exceed current and future government funding. Medarex and
      PharmAthene will share profits according to a formula that is affected by the
      following factors: (i) whether a contract for the procurement of Valortim(tm)
      is
      entered into with the U.S. Government; (ii) whether PharmAthene has contributed
      funding in an amount equivalent to the funding provided by the U.S. Government
      to Medarex via grants awarded to fund Valortim(tm) development work; and (iii)
      whether PharmAthene provides funding that exceeds the matching by PharmAthene
      of
      funds provided to Medarex under (ii) above. Under the formula, PharmAthene's
      share of operating profits could increase from its initial level of 20% to
      as
      high as 60%.

    If
      you
      have any questions, please contact the undersigned at 212-370-1300, or Matthew
      P. Kinley, the Company’s President, at 515-244-5746.

              Very
                truly yours,

              ELLENOFF
                GROSSMAN & SCHOLE LLP.

              By:

              Brian
                C. Daughney

              Brian
                C. Daughney

            cc:

              Mr.
                Matthew P. Kinley

    Jeffrey
      Baumel, Esq.

CORRESP
1
filename1.htm

      Unassociated Document

    June
      28,
      2007

    VIA
      FEDERAL EXPRESS AND EDGAR

    United
      States Securities and Exchange Commission

    Office
      of
      Emerging Growth Companies

    100
      F
      Street, NE - Mail Stop 3561

    Washington,
      D.C. 20549

    Attn: Mr.
      Duc
      Dang

            Re:

            Healthcare Acquisition Corp. Preliminary
              Proxy Statement on Schedule 14A

            Filed on February 9, 2007 as subsequently
              amended by

            Amendment No.1 to Preliminary Proxy
              Statement
              on Schedule 14A

            Filed April 20, 2007; and

            Amendment No. 2 to Preliminary Proxy
              Statement on Schedule 14A

            Filed June 8, 2007

            File No.
              001-32587

    Ladies
      and Gentlemen:

    On
      behalf
      of Healthcare Acquisition Corp. (the “Company”
or
      “HAQ”),
      we
      are electronically transmitting hereunder Amendment No. 3 (“Amendment
      No. 3”)
      to the
      Preliminary Proxy Statement (the “Proxy
      Statement”)
      filed
      with the Securities and Exchange Commission (the “Commission”)
      on
      February 9, 2007 and subsequently amended by filing of Amendment No. 1 filed
      on
      April 20, 2007 (“Amendment
      No. 1”)
      and
      Amendment No. 2 filed on June 8, 2007 (“Amendment
      No. 2”)
      together with this letter which responds to the Staff’s comments to Amendment
      No. 2 set forth in a letter from John Reynolds, Assistant Director, dated June
      26, 2007 addressed to John Pappajohn, Chairman of the Board of the Company.
      Marked courtesy copies of this filing are being sent via overnight courier
      to
      Messrs. John Reynolds, Duc Dang and David Walz.

    We
      are
      authorized by the Company to provide the responses contained in this letter
      on
      behalf of the Company. In this letter, we have recited the comments from the
      Staff in bold and have followed each comment with the Company’s response.
      .

    As
      we
      have indicated in our telephone conversations with the Staff, we appreciate
      any
      assistance that the Staff can provide to complete this review. As we have
      previously advised, HAQ must complete the acquisition before August 3, 2007
      or
      it will be required to liquidate. As a result, HAQ needs to be in a position
      to
      mail the Proxy Statement no later than July 9th
      to allow
      sufficient time for solicitation. As a consequence, in accordance with Rule
      14a-6(d) of the Securities Exchange Act of 1934, as amended, we have indicated,
      and hereby advise the Staff, that the Company intends to mail on July 9,
      2007.

    Interests
      of HAQ Directors and Officers in the Merger, page 20

            1.

              Please
                revise to clarify why the disclosure in the table of this subsection
                does
                not include the securities purchased in open market transactions.

      HAQ
        did
        not include disclosure in this table of the securities purchased in the open
        market transactions because this table is meant to illustrate the
        unrealized profits with respect to the securities held by HAQ’s officers and
        directors which, if the merger is not consummated, will be worthless. The
        securities purchased in the open market transactions under the 10b-5 plans
        may
        be sold in the open market and, if the merger is not consummated, will
        participate in the liquidation of the trust. The Proxy Statement has been
        revised at page 21 to clarify this point in accordance with
        Staff's comment.

    Risk
      Factors, page 32

    The
      Board of Directors of HAQ did not obtain any fairness opinion …, page 32

            2.

              We
                note the disclosure in this risk factor that "[c]urrent HAQ stockholders
                and prospective investors must rely on their own business and investment
                background, and their own investigation of PharmAthene ....” Please advise
                us of the basis for disclosing that your shareholders have to make
                their
                own investigation of PharmAthene. Clarify if you have provided all
                the
                material information needed for shareholders to make an informed
                decision.

      We
        have
        revised the Proxy Statement to remove the above-referenced disclosure. We
        have
        also included a statement that HAQ has provided in the Proxy Statement all
        material information. The revised disclosure appears on page 32 of the
        Proxy Statement.

    A
      stockholder may make a claim …, page 32

              3.

                We
                  note your response to comment 12 of our letter dated June 1, 2007.
                  We
                  continue to note that the specific language that your board “did not
                  determine a specific valuation of PharmAthene at the time it entered
                  into
                  the merger agreement" was removed in your first amendment. Please
                  revise
                  the subheading of this risk factor to highlight that you "did not
                  determine a specific valuation of PharmAthene at the time it entered
                  into
                  the merger
                  agreement.”

      We
        have
        revised the subheading of this risk factor to highlight the fact that HAQ’s
        Board did not determine a specific valuation at that time. The revised
        disclosure appears on page 32 of the Proxy Statement.

    Failure
      to consummate the Merger could negatively impact the market price …, page 32

            4.

              We
                note in the last bullet point in this risk factor that “charges will be
                made against earnings for this transaction-related expenses, which
                could
                be higher than expected.” Please revise to elaborate in this bullet point
                or later in the document. Clarify if these expenses were subject
                to the
                waivers discussed in your public offering prospectus. Also quantify
                the
                expenses so that investors can understand the magnitude of the risk.

        2

      We
        have
        revised the Proxy Statement to remove that bullet point and expand upon the
        disclosure to clarify and disclose that those expenses have not
        been waived and to quantify the liabilities which have not been waived, in
        consistent with prior disclosure elsewhere in the proxy statement. In fact
        the
        bullet point is not actually relevant to the risk factor because if we fail
        to
        consummate the merger we will liquidate and there will be no charges against
        earnings. The revised disclosure appears on page 32 of the Proxy
        Statement.

    Background
      of the Merger, page 57

            5.

              We
                note your response to comment 16 of our letter dated June 1, 2007.
                We also
                note the disclosure of the range in value of SIGA’s shares from $118.7 to
                $162.5 million. Considering the termination by SIGA of the merger
                agreement occurred as it was receiving progressively positive news
                regarding the advancement of its smallpox drug, it would appear that
                the
                price increase in SIGA’s shares was also result of such positive news. As
                such, it appears appropriate to disclose the value of the merger
                consideration only on the date the merger agreement was originally
                signed.
                Please revise to just disclose the value of the prior merger consideration
                on the date of the execution of the merger agreement or advise.

      We
        have
        revised the Proxy Statement to disclose the value of the merger consideration
        on
        the date the SIGA merger agreement was signed and to remove the range of
        values.
        The revised disclosure appears on page 60 of the Proxy
        Statement.

    HAQ’s
      Reasons for the Merger and Recommendation of the HAQ Board, page 66

            6.

              We
                note your response to comment 18 of our letter dated June 1, 2007.
                We also
                note disclosure on page 61 and page 67 that you used projections
                of
                revenue provided by the target. You disclose on page 61 that you
                did not
                assign a specific weight to them, however, you based your analysis
                on
                those projections. Please revise your disclosure to balance the noted
                disclosure that you did not assign a specific weight to them to highlight
                the fact that you used those projections in your valuation which
                lead to
                your determination to recommend the transaction to shareholders.

      We
        have
        revised the Proxy Statement to highlight the fact that HAQ in fact relied
        upon those projections in the overall analysis which lead to the
        determination to recommend the transaction to shareholders, without necessarily
        assigning any specific weight to them in its analysis. The revised disclosure
        appears on page 61 of the Proxy Statement.

            7.

              We
                note the revenue projections for 2008 and 2009 of $67.S and $168.8
                million, respectively. Please revise to clarify if this means you
                expect
                to have commercially viable products by 2008. If not, please clarify
                what
                type of revenues the projections encompass. As a general matter,
                please
                revise to disclose the reasonable basis for the projections. Please
                refer
                to Item 10(b) of Regulation S-K.

        3

    Considering
      the projections were provided by PharmAthene management and the MD&A
      disclosure is management's forward looking prospective of the target, please
      revise your MD&A disclosure of PharmAthene to discuss the progress of the
      target going forward pertaining to the development of the two drugs and the
      eventual commercial sales. In that regard, please clarify how management's
      forward looking prospective relates to its projections.

      We
        have
        revised the disclosure to indicate that PharmAthene currently estimates that
        it
        will not have an FDA approved product until at least 2012. As such,
        PharmAthene’s revenue projections for the years 2008 and 2009 contemplate that a
        commercially saleable product will not have received FDA approval at those
        times. The applicable sections have been revised to (i) provide additional
        information that established the reasonable basis for the projections and
        (ii)
        conform to Item 10 of Regulation S-K. We also revised the disclosure to clarify
        how PharmAthene derived its projections for 2008 and 2009. The revised
        disclosure appears on page 68 of the Proxy Statement. The MD&A has also
        been conformed at page 101 of the proxy statement.

            8.

              We
                note that you also used revenue projections for the “comparable companies”
                obtained from “equity research analyst reports.” Please revise to discuss
                the reason you had to use revenue projections instead of actual revenues
                for the comparable companies. Did those companies have no sales revenues
                also? Also, please revise to clarify if the projections provided
                by the
                target are comparable to the projections in the “equity research analyst
                reports.”

      In
        response to the Staff’s comment, we have revised the Proxy Statement to discuss
        why HAQ’s management used revenue projections rather than actual revenues for
        the comparable companies. In addition, we have revised the disclosure to
        clarify
        that the projections were prepared using similar methods and criteria as
        considered by research analysts in reviewing and providing revenue estimates
        for
        the peer group companies. The revised disclosure appears on page 66 of the
        Proxy Statement.

            9.

              Since
                you disclose the companies listed on page 67 as comparable, please
                revise
                to clarify if all of them have only products that are not yet on
                the
                market. Clarify the number of products those companies develop and
                sell.
                If known, discuss the stage at which the companies are at in their
                FDA
                approval process and compare it with your drugs.

      In
        response to the Staff’s comment, we have revised the Proxy Statement to clarify
        that two of the five peer companies have product revenues and have inserted
        a
        chart which sets forth the development of relevant products for each
        company and a comparison thereof to PharmAthene’s products. The revised
        disclosure appears on page 66 of the Proxy Statement.

            10.

              In
                your “multiple analysis,” we note that your calculation was based on the
                “enterprise value for HAQ on a post merger basis assuming various
                HAQ
                stock prices.” (Emphasis added.) It is not clear how it is appropriate and
                consistent with your public offering prospectus to use a “post merger
                basis” in your valuations. Please revise to clarify. Please note that a
                post merger basis appears to imply that the funds in the trust are
                taken
                into account when determining the value, which does not appear consistent
                with the disclosure in your prospectus.

        4

      In
        response to the Staff’s comment, we have revised the section in the Proxy
        Statement to clarify that the multiple analysis was simply an analysis conducted
        by management to "check" the other analysis conducted and to present to the
        Board certain hypothetical information. It was not necessarily the analysis
        used
        to establish the valuation, rather to provide additional background and
        confirmatory information to the Board. The revised disclosure appears on
        page 68 of the Proxy Statement.

            11.

              We
                note that the “multiple analysis” requires assumed share prices. Please
                revise to provide the basis for the assumed prices. It is not clear
                how an
                analysis that uses assumed stock prices is relevant to an investor’s
                evaluation of their vote, since the share price ultimately determines
                the
                value. Please clarify.

      In
        response to the Staff’s comment, we have revised the Proxy Statement to remove
        the table setting forth the multiple price analysis to avoid providing
        additional information that might not be relevant to an investor's evaluation
        of
        their vote.

            12.

              We
                note your

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549-7010

       DIVISION OF
CORPORATION FINANCE

Mail Stop 3561
 June 26, 2007

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
2116 Financial Center
666 Walnut Street
Des Moines, Iowa 50309

 Re: Healthcare Acquisition Corp
  Amendment No. 2 to Preliminary Proxy Statement on
  Schedule 14A
  Filed June 8, 2007
  File No. 001-32587

Dear Mr. Pappajohn:

We have reviewed your filing and have the following comments.  Where
indicated, we think you should revise your document in response to these comments.  If
you disagree, we will consider your explanation as to why our comment is inapplicable or a revision is unnecessary.  Please be as detailed as necessary in your explanation.  In some of our comments, we may ask you to provide us with supplemental information so we may better understand your disclosure.  After reviewing this information, we may or may not raise additional comments.

Please understand that the purpose of our review process is to assist you in your
compliance with the applicable disclosure requirements and to enhance the overall disclosure in your filing.  We look forward to working with you in these respects.  We welcome any questions you may have about our comments or on any other aspect of our review.  Feel free to call us at the telephone numbers listed at the end of this letter.

Interests of HAQ Directors and Officers in the Merger, page 20

1. Please revise to clarify why the disclosure in the table of this subsection does not include the securities purchased in open market transactions.

Risk Factors, page 32

The Board of Directors of HAQ did not obtain any fairness opinion. . . ., page 32

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp June 26, 2007
Page 2

2. We note the disclosure in this risk factor that “[c]urrent HAQ stockholders
and prospective investors must rely on their own business and investment background, and their own investigation of PharmAthene . . . .”  Please advise us of the basis for disclosing that your shareholders have to make their own investigation of PharmAthene.  Clarify if you have provided all the material information needed for shareholders to make an informed decision.

A stockholder may make a claim. . . ., page 32

3. We note your response to comment 12 of our letter dated June 1, 2007.  We continue to note that the specific language that your board “did not determine a specific valuation of PharmAthene at the time it entered into the merger agreement” was removed in your first amendment.  Please revise the subheading of this risk factor to highlight that you “did not determine a specific valuation of PharmAthene at the time it entered into the merger agreement.”

Failure to consummate the Merger could negatively impact the market price. . . ., page 32

4. We note in the last bullet point in this risk factor that “charges will be made against earnings for this transaction-related expenses, which could be higher than expected.”  Please revise to elaborate in this bullet point or later in the document.  Clarify if these expenses were subject to the waivers discussed in your public offering prospectus.  Also quantify the expenses so that investors can understand the magnitude of the risk.

Background of the Merger, page 57

5. We note your response to comment 16 of our letter dated June 1, 2007.  We also note the disclosure of the range in value of SIGA’s shares from $118.7 to $162.5 million.  Considering the termination by SIGA of the merger agreement occurred as it was receiving progressively positive news regarding the advancement of its smallpox drug, it would appear that the price increase in SIGA’s shares was also result of such positive news.  As such, it appears appropriate to disclose the value of the merger consideration only on the date the merger agreement was originally signed.  Please revise to just disclose the value of the prior merger consideration on the date of the execution of the merger agreement or advise.

HAQ’s Reasons for the Merger and Recommendation of the HAQ Board, page 66

6. We note your response to comment 18 of our letter dated June 1, 2007.  We also note disclosure on page 61 and page 67 that you used projections of revenue provided by the target.  You disclose on page 61 that you did not

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp June 26, 2007
Page 3

assign a specific weight to them, however, you based your analysis on those
projections.  Please revise your disclosure to balance the noted disclosure that you did not assign a specific weight to them to highlight the fact that you used those projections in your valuation which lead to your determination to recommend the transaction to shareholders.

7. We note the revenue projections for 2008 and 2009 of $67.5 and $168.8 million, respectively.  Please revise to clarify if this means you expect to have commercially viable products by 2008.  If not, please clarify what type of revenues the projections encompass.  As a general matter, please revise to disclose the reasonable basis for the projections.  Please refer to Item 10(b) of Regulation S-K.

Considering the projections were provided by PharmAthene management and the MD&A disclosure is management’s forward looking prospective of the target, please revise your MD&A disclosure of PharmAthene to discuss the progress of the target going forward pertaining to the development of the two drugs and the eventual commercial sales.  In that regard, please clarify how management’s forward looking prospective relates to its projections.

8. We note that you also used revenue projections for the “comparable companies” obtained from “equity research analyst reports.”  Please revise to discuss the reason you had to use revenue projections instead of actual revenues for the comparable companies.  Did those companies have no sales revenues also?  Also, please revise to clarify if the projections provided by the target are comparable to the projections in the “equity research analyst reports.”

9. Since you disclose the companies listed on page 67 as comparable, please revise to clarify if all of them have only products that are not yet on the market.  Clarify the number of products those companies develop and sell.  If known, discuss the stage at which the companies are at in their FDA approval process and compare it with your drugs.

10. In your “multiple analysis,” we note that your calculation was based on the “enterprise value for HAQ on a
post merger basis  assuming various HAQ
stock prices.”  (Emphasis added.)  It is not clear how it is appropriate and consistent with your public offering prospectus to use a “post merger basis” in your valuations.  Please revise to clarify.  Please note that a post merger basis appears to imply that the funds in the trust are taken into account when determining the value, which does not appear consistent with the disclosure in your prospectus.

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp June 26, 2007
Page 4

11. We note that the “multiple analysis” requires assumed share prices.  Please
revise to provide the basis for the assumed prices.  It is not clear how an analysis that uses assumed stock prices is relevant to an investor’s evaluation of their vote, since the share price ultimately determines the value.  Please clarify.

12. We note your response to comment 39 and the disclosure in the first bullet point on page 69 that the “historical investments by recognized venture capital investors” is a factor you considered in making the decision to enter into the merger agreement and recommend a vote “for” the merger.  Please revise to clearly disclose what these investments were and clarify how they are relevant.  You refer to the investors’ valuations.  Please revise to elaborate on their valuation as you convey their relevance to shareholders here.  Also, please revise to clarify how the valuations by private investors would also take into account the fact that they are able to place members on the board of directors.

13. We note the disclosure in the last paragraph on page 69 that the target is a “leading company” based on it having “possible” products.  Please tell us the basis for the disclosure that the target company is a leading company based on possible products.  Also, you disclose that the two contracts are the basis for describing the company as a leading company.  Please tell us why it is appropriate to base such promotional disclosure on contracts that are not fully funded.

14. Please revise to elaborate on the negative factors disclosed on page 70.  For instance, please quantify the “significant amount of capital needed to be competitive” and the liabilities of the target that will be assumed.  Also, please compare the targets assets to its liabilities.

Management’s Discussion and Analysis, page 101

15. We note the additional disclosure in response to comment 50 that you did not receive any of the funds awarded to Medarex.  In the subsection captioned “future cash needs,” please revise to discuss how the target will be able to fund your development of both Valortim and Protexia.  We note the revised disclosure throughout this document that the contract with the DoD was for $35 million.  Please revise to discuss the timeline and how the $35 million will be earned considering Protexia has not yet been approved and is still in development.

Information About Pharmathene, page 111

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp June 26, 2007
Page 5

16. We note your response to comment 49 of our letter dated June 1, 2007 that the
agreement you have in place with Medarex is confidential.  We also note that you only have two drugs in production and one of them is in partnership with Medarex.  As such, it appears that the terms of the target’s relationship with Medarex are material to investors’ understanding of your business going forward.  Also, upon consummation of the merger, material contacts will be filed with the Commission.  Because of  the material nature of this
relationship, please advise us of the basis for not disclosing the material terms here.

Beneficial ownership following the merger, page 153

17. Please revise to identify the natural person that is considered the beneficial holder of the securities held by QVT Financial LP.

* * * *

As appropriate, please amend your proxy statement in response to these
comments.  You may wish to provide us with marked copies of the amendment to expedite our review.  Please furnish a cover letter with your amendment that keys your responses to our comments and provides any requested supplemental information.  Detailed cover letters greatly facilitate our review.  Please understand that we may have additional comments after reviewing your amendment and responses to our comments.

  We urge all persons who are responsible for the accuracy and adequacy of the disclosure in the filing to be certain that the filing includes all information required under the Securities Exchange Act of 1934 and that they have provided all information investors require for an informed investment decision.  Since the company and its management are in possession of all facts relating to a company’s disclosure, they are responsible for the accuracy and adequacy of the disclosures they have made.

You may contact David Walz at (202) 551-3358 if you have questions regarding
the financial statements and related matters.  Please contact Duc Dang at (202) 551-3386 with any other questions.

Sincerely,

John Reynolds, Assistant Director
Office of Emerging Growth Companies

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp June 26, 2007
Page 6

cc:  Brian Daughney
       (212) 370-1300

CORRESP
1
filename1.htm

      Unassociated Document

      June
        8,
        2007

    VIA
      FEDERAL EXPRESS AND EDGAR

    United
      States Securities and Exchange Commission

    Office
      of
      Emerging Growth Companies

    100
      F
      Street, NE - Mail Stop 3561

    Washington,
      D.C. 20549

    Attn: Mr.
      Duc
      Dang

                Re:

                Healthcare
                  Acquisition Corp. Preliminary Proxy Statement on Schedule
                  14A

                Filed
                  on February 9, 2007 as subsequently amended by

                Amendment
                  No.1 to Preliminary Proxy Statement on Schedule 14A

                Filed
                  April 20, 2007

                File
                  No. 001-32587

    Ladies
      and Gentlemen:

    On
      behalf
      of Healthcare Acquisition Corp. (the “Company”
or
      “HAQ”),
      we
      are electronically transmitting hereunder Amendment No. 2 (“Amendment
      No. 2”)
      to the
      Preliminary Proxy Statement (the “Proxy
      Statement”)
      filed
      with the Securities and Exchange Commission (the “Commission”)
      on
      February 9, 2007 and subsequently amended by filing of Amendment No. 1 filed
      on
      April 20, 2007 (“Amendment
      No. 1”)
      together with this letter which responds to the Staff’s comments to Amendment
      No. 1 set forth in a letter from John Reynolds, Assistant Director, dated June
      1, 2007 addressed to John Pappajohn, Chairman of the Board of the Company.
      Marked courtesy copies of this filing are being sent via overnight courier
      to
      Messrs. John Reynolds, Duc Dang, David Link and David Walz.

    We
      are
      authorized by the Company to provide the responses contained in this letter
      on
      behalf of the Company. In this letter, we have recited the comments from the
      Staff in bold and have followed each comment with the Company’s response. Please
      note that the entire filing has been modified and updated to reflect the
      inclusion of unaudited financial statements for each of HAQ and PharmAthene,
      Inc. at March 31, 2007, as well as the corresponding management’s discussion and
      analysis.

      As
        we
        have indicated in our telephone conversations with the Staff, we appreciate
        any
        assistance that the Staff can provide to complete this review. As we have
        previously advised, HAQ must complete the acquisition before August 3, 2007
        or
        it will be required to liquidate. As a result, HAQ needs to be in a position
        to
        mail the Proxy Statement no later than June 22nd
        to allow
        sufficient time for solicitation. As a consequence, in accordance with Rule
        14a-6(d) of the Securities Exchange Act of 1934, as amended, we have indicated,
        and hereby advise the Staff, that the Company intends to mail on June 22,
        2007.

    General
      Response

    As
      an
      overall response to the Staff’s comment letter, we note that a substantial
      number of the Staff’s comments relate to the issue of the valuation analysis
      undertaken by the HAQ Board of Directors and its determination of fairness
      of
      the transaction from a financial point of view. We appreciate that the amount
      of
      the merger consideration actually being paid may not always be reflective of
      the
      value of the target. We further acknowledge that disclosures in the prior
      filings of the Proxy Statement may have been insufficient disclosure regarding
      the valuation analysis that was undertaken. As we briefly discussed in our
      telephone conference with the Staff on Tuesday June 5th,
      there
      appears to have been lack of clarity in the prior filings regarding the value
      determination process and the factors analyzed by the HAQ Board of Directors
      in
      determining that the 80% net asset value requirement had been satisfied. We
      have, therefore, revised the disclosure in the discussion of the valuation
      process undertaken by the Board of Directors in several sections throughout
      the
      Proxy Statement to clarify that, while a specific dollar value was not ascribed
      to PharmAthene, a value range was determined.

    However,
      as previously noted, the HAQ Board of Directors neither sought nor obtained
      any
      third party valuation analysis or fairness opinion, nor undertook the type
      of
      valuation analyses which might have otherwise been included in a third party
      fairness opinion. We have expanded disclosure in this regard and highlighted
      this fact in a number of sections of Amendment No. 2 to the Proxy Statement
      to
      fully apprise stockholders and investors of the limitations of the review and
      analyses undertaken by the HAQ Board.

    For
      example, we have included the following disclosure (or variations thereof)
      in
      the Notice of Meeting and letter to stockholders and Summary section, as well
      as
      in a Risk Factor:

    “No
      fairness opinion or valuation analysis from an independent third party was
      obtained with respect to the Merger Proposal or the value of PharmAthene. The
      Board of Directors of HAQ has determined that the fair market value of
      PharmAthene exceeds 80% of HAQ’s net assets and that the terms of the Merger are
      in the best interest of and fair to the stockholders. Such determination with
      respect to the proposed Merger and the consideration being paid for PharmAthene
      was based upon various factors as described in the enclosed proxy statement
      including the Board’s internal analyses of PharmAthene’s business, technology
      and future prospects, PharmAthene’s management and historical investments by
      third parties into PharmAthene.”

      We
        have
        also included disclosure in the Question and Answer section and similar
        disclosure in the discussions under the headings “Background of the Merger” at
        pages 57 to 66 and “HAQ’s Reasons for the Merger and Recommendation of the
        HAQ Board” at pages 66 to 70.

    General

              1.

              We
                note your response to comment one of our letters dated March 20,
                2007
                concerning the disclosure that your board did not determine a specific
                value for the target. Please revise the letter and notice to your
                stockholders and summary section to highlight the fact that you did
                not
                determine the value of the target when you decided to enter into
                the
                business combination agreement. Please note that a determination
                of value
                and the purchase price are different issues.

      The
        letter to stockholders and Notice of Meeting and Summary of the Terms at
        page 2
        and the Summary section at page 18 have been revised to clarify the extent
        to
        which, rather than determining a specific value for the target prior to
        execution of the letter of intent, HAQ undertook analyses to establish a
        value
        range. Conforming disclosure has been included under the sections entitled
        “Background of the Merger” at pages 57 through 66 and “HAQ’s Reasons for the
        Merger and Recommendation of the HAQ Board” at pages 66 through
        70.

              2.

              We
                note your response to comment 41 of our letter dated March 20, 2007
                that
                you determined that the price negotiated by the parties reflected
                the
                value of the target. Based on your previous disclosure, you did not
                determine the value of the target prior to entering into the merger
                agreement. If so, please revise the appropriate section to clarify
                that
                you determined the consideration to offer the sellers without first
                determining the value of the target. Also, please clearly explain
                how you
                negotiated the consideration without first determining a value for
                the
                target.

      We
        have
        included two new paragraphs at the bottom of page 61 in order to clarify
        that a value, within a range, was established by the HAQ Board prior to the
        submission of the initial letter of intent even though no specific value
        was
        assigned to PharmAthene. We have further expanded upon the negotiation process
        throughout the "Background of the Merger" section at pages 57 to 66.

              3.

              Please
                revise to include management compensation disclosure in the document
                for
                the target’s management during the past year. The CD&A disclosure
                needs to include appropriate disclosure regarding the plan going
                forward
                after the merger to include any employment agreements or other
                compensation arrangements entered into or amended as a result of
                the
                merger. Please refer to Item 402 of Regulation S-K. Additionally,
                revise
                to include Item 404 of Regulation S-K disclosure for PharmAthene.

      We
        have
        provided compensation disclosure regarding PharmAthene’s last fiscal year as
        well as CD&A disclosure for PharmAthene commencing at page 124 of the
        Proxy Statement. Additionally, CD&A relating to compensation plans for the
        combined company going forward after the merger is included at page 146 of
        the Proxy Statement.

    Notice
      of Special Meeting

              4.

              We
                note your statement that “[i]f the Merger Proposal is not approved,
                it
                is likely that HAQ will have insufficient time and resources to seek
                another suitable business combination
                and will have to commence the winding up, dissolution and liquidation
                of
                HAQ ...” (emphasis added). We also note your statements in the Form S-1
                that “If we enter into either a letter of intent, an agreement in
                principle or a definitive agreement to complete a business combination
                prior to the expiration of 18 months after the consummation of this
                offering, but are unable to complete the business combination within
                the
                18-month period, then we will have an additional six months in which
                to
                complete the business combination contemplated by the letter of intent,
                agreement in principle or definitive agreement. If we are unable
                to do so
                by the expiration of the 24-month period from the consummation of
                this
                offering, we will then liquidate.” Please revise to clarify throughout the
                proxy that if the merger proposal is not approved then HAQ will have
                to
                commence the winding up, dissolution and liquidation of
                HAQ.

      We
        have
        revised the disclosure throughout the Proxy Statement to clarify that if
        the
        Merger Proposal is not approved, HAQ will have to commence the winding up,
        dissolution and liquidation of HAQ; please see, in particular, the Notice
        to
        Stockholders and pages 4, 8, 9, 15, 72 and 135.

    Summary
      of the Material Terms of the Merger, page 1

              5.

              Here
                and where you discuss the basis for the consideration being offered
                to
                PharmAthene, please revise to quantify, to the extent practicable,
                the
                value of such
                consideration.

      We
        have
        revised the disclosure throughout the Proxy Statement to include reference
        to
        the potential aggregate value of the merger consideration; please see in
        particular, the letter to stockholders, Notice of Meeting holders and pages
        2,
        7, and 18, and 57.

              6.

              Please
                revise to clarify in the penultimate bullet point on page two that
                the
                board also did not make a determination as to the value of the target.

    As
      noted
      in the general response above, we have provided revised disclosure on this
      issue
      in various sections of the Proxy Statement including in the penultimate bullet
      point on page 2 to indicate that the Board reviewed information relating to
      a
      value range for PharmAthene.

    What
      happens if the Merger is not consummated, page 9

              7.

              We
                note your response to comment 17 of our letter dated March 20, 2007.
                We
                reissue the comment. Please revise to quantify your current outstanding
                liability and disclose the amount covered by waivers.

    We
      have
      modified the disclosure at pages 9 and 132 to provide more extensive disclosure
      in response to the Staff’s comment to detail the exact amounts of any
      outstanding liabilities and the amount of liabilities covered by waivers.

    Summary
      of the Proxy Statement, page 11

              8.

              We
                note your response to comment 18. Please revise to clarify that the
                combination must be with a target business or for assets
                whose
                fair market value
                is at least equal to 80% of the net assets of HAQ at the time of
                such
                acquisition.

    We
      have
      provided revised disclosure at page 11 in accordance with the Staff’s comment to
      address the 80% requirement.

              9.

              We
                note the disclosure on page 12 that “stockholders holding an aggregate of
                up to 2,328,835 shares of common stock could convert such shares
                and the
                merger may still be consummated.” It is not clear how you arrived at that
                figures since it appears to be greater than 20% of the shares issued
                in
                your initial public offering. Your disclosure on page 16 indicates
                that if
                1,880,000 or more shares exercise conversion the merger will not
                be
                consummated. Please revise to clarify.

      We
        note
        the Staff’s comment and advise the Staff that the reference to 2,328,835 shares
        was a typographical error; this has been corrected at page 15 of the Proxy
        Statement.

              10.

              We
                note the additional disclosure on page 16 concerning the open market
                purchases by your officers and directors. In the appropriate sections,
                please revise to discuss the parameters of these purchase plans.

      We
        have
        added footnote disclosure to detail the stock purchase plans adopted by certain
        members of the HAQ Board and management team. The disclosure is repeated
        on
        pages 17, 55, 56, 149 and 152 of the Proxy Statement.

    Risk
      Factors

              11.

              We
                note your revisions to risk factor 2. Please reinsert your discussion
                addressing your first product Dominate Negative Inhibitor and that

Mail Stop 3561

 June 1, 2007

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
2116 Financial Center
666 Walnut Street
Des Moines, Iowa 50309

 Re: Healthcare Acquisition Corp
  Preliminary Proxy Statement
  Filed on February 9, 2007
  File No. 1-32587

Dear Mr. Pappajohn:

We have reviewed your filing and have the following comments.  Where
indicated, we think you should revise your document in response to these comments.  If
you disagree, we will consider your explanation as to why our comment is inapplicable or a revision is unnecessary.  Please be as detailed as necessary in your explanation.  In some of our comments, we may ask you to provide us with supplemental information so we may better understand your disclosure.  After reviewing this information, we may or may not raise additional comments.

Please understand that the purpose of our review process is to assist you in your
compliance with the applicable disclosure requirements and to enhance the overall disclosure in your filing.  We look forward to working with you in these respects.  We welcome any questions you may have about our comments or on any other aspect of our review.  Feel free to call us at the telephone numbers listed at the end of this letter.

General

1. We note your response to comment one of our letter dated March 20, 2007 concerning the disclosure that your board did not determine a specific value for the target.  Please revise the letter and notice to your stockholders and summary section to highlight the fact that you did not determine the value of the target when you decided to enter into the business combination agreement.  Please note that a determination of value and the purchase price are different issues.

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
June 1, 2007 Page 2

2. We note your response to comment 41 of our letter dated March 20, 2007 that you determined that the price negotiated by the parties reflected the value of the target.  Based on your previous disclosure, you did not determine the value of the target prior to entering into the merger agreement.  If so, please revise the appropriate section to clarify that you determined the consideration to offer the sellers without first determining the value of the target.  Also, please clearly explain how you negotiated the consideration without first determining a value for the target.

3. Please revise to include management compensation disclosure in the document for the target’s management during the past year.  The CD&A disclosure needs to include appropriate disclosure regarding the plan going forward after the merger to include any employment agreements or other compensation arrangements entered into or amended as a result of the merger.  Please refer to Item 402 of Regulation S-K.  Additionally, revise to include Item 404 of Regulation S-K disclosure for PharmAthene.

Notice of Special Meeting

4. We note your statement that “[i]f the Merger Proposal is not approved, it is
likely that HAQ will have insufficient time and resources to seek another
suitable business combination  and will have to commence the winding up,
dissolution and liquidation of HAQ ….” (e mphasis added). We also note your
statements in the Form S-1 that “If we enter into either a letter of intent, an agreement in principle or a definitive agreement to complete a business combination prior to the expiration of 18 months after the consummation of this offering, but are unable to complete the business combination within the 18-month period, then we will have an additional six months in which to complete the business combination contemplated by the letter of intent, agreement in principle or definitive agreement. If we are unable to do so by the expiration of the 24-month period from the consummation of this offering, we will then liquidate.”  Please revise to clarify throughout the proxy that if the merger proposal is not approved then HAQ will have to commence the winding up, dissolution and liquidation of HAQ.

Summary of the Material Terms of the Merger, page 1

5. Here and where you discuss the basis for the consideration being offered to PharmAthene, please revise to quantify, to the extent practicable, the value of such consideration.

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
June 1, 2007 Page 3

6. Please revise to clarify in the penultimate bullet point on page two that the board also did not make a determination as to the value of the target.

What happens if the Merger is not consummated, page 9

7. We note your response to comment 17 of our letter dated March 20, 2007.  We reissue the comment.  Please revise to quantify your current outstanding liability and disclose the amount covered by waivers.

Summary of the Proxy Statement, page 11

8. We note your response to comment 18.  Please revise to clarify that the combination must be with a target business or for assets whose
fair market
value  is at least equal to 80% of the net assets of HAQ at the time of such
acquisition.

9. We note the disclosure on page 12 that “stockholders holding an aggregate of up to 2,328,835 shares of common stock could convert such shares and the merger may still be consummated.”  It is not clear how you arrived at that figures since it appears to be greater than 20% of the shares issued in your initial public offering.  Your disclosure on page 16 indicates that if 1,880,000 or more shares exercise conversion the merger will not be consummated.  Please revise to clarify.

10. We note the additional disclosure on page 16 concerning the open market purchases by your officers and directors.  In the appropriate section, please revise to discuss the parameters of these purchase plans.

Risk Factors

11. We note your revisions to risk factor 2.  Please reinsert your discussion addressing your first product Dominate Negative Inhibitor and that the program was subsequently terminated.

12. We note the revision in the first risk factor on page 39 removing the language that your board “did not determine a specific valuation of PharmAthene at the time it entered into the merger agreement.”  Please advise why the noted disclosure has been removed.  Also, please revise to clarify that you determined the price to be fair without first determining the value of the

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
June 1, 2007 Page 4
target, if true.

13. We note your response to comment 39.  We continue to believe that you should more prominently disclose the risk factors “There was no independent valuation of PharmAthene undertaken by HAQ …” and “A stockholder may make a claim against HAQ for taking actions inconsistent with the IPO prospectus ….”

Conversion Rights, page 48

14. We note your response to comment six of our letter dated March 20, 2007 and the revised disclosure on page 48.  Please revise to specifically disclose the deadline which shareholders have to tender their shares in order to receive a pro-rata portion of the trust account if they exercise conversion.

Background of the Merger, page 51

15. We note your response to comment 52 of our letter dated March 20, 2007 that you have revise page 52 to highlight 18 month deadline you were required to locate a target.  We are not able to locate your response on page 52 of the proxy.  It appears you instead disclosed the 24 month deadline.  When discussing your negotiations with the target, please revise to highlight the proximity of the 18 month deadline by which you were required to at least locate a target.

16. We note the additional disclosure on page 54 that the consideration value for the target offered by SIGA would have increased to $414.5 million following SIGA’s announcement of news about one of its products.  It is not clear how the increase in the SIGA consideration to $414.5 million is relevant given that announcement occurred after the termination of the merger agreement.  Please clarify.

17. We note that you deleted your prior disclosure indicated that “there were no pre-existing relationships between any of our initial stockholders and any insiders of PharmAthene.”  Revise to include that disclosure or clarify the pre-existing relationships.

18. We note that on October 12, 2006 PharmAthene provided Mr. Kinley and Dr. Schaffer certain financial information which included projections and cash flow analyses.  Advise us who prepared the projections.  Supplementally provide us with these projections.  In addition, please provide us with a

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
June 1, 2007 Page 5
detailed analysis for any conclusion that the non-public information is not material and therefore need not be disclosed.  We may have further comment.

19. We note the revised disclosure on page 55 that on October 24, 2006, Mr. Kinley spoke with Messrs. Berger, Schellhammer, Pappajohn and Dr. Schaffer to review “the proposed valuation.”  Please revise to identify the party that performed the valuation.

20. We note your response to comment 55 that The Maxim Group prepared no reports or presentations to the board members prior to the board’s determination on January 16, 2007 to approve the merger.  We cannot locate your disclosure that there were no presentations or reports prepared by The Maxim Group prior to the board’s determination on January 16, 2007 to approve the merger.   Additionally, address whether any presentations or reports were prepared by the company’s management concerning PharmAthene’s valuation that were presented to board members.

21. We note your response to comment 53.  Revise to indicate that The Maxim Group did not provide any written or formal analysis in determining the consideration to be paid to the PharmAthene security holders.  Additionally, we note that the Maxim Group was consulted on numerous occasions regard to the valuation of PharmAthene.  Discuss in detail the services provided by The Maxim Group in connection with the valuation of PharmAthene.

22. We note your response to comment 53.  Revise to indicate the valuation analyses performed by the Board of Directors prior to or during the merger negotiations until the Board approved the merger on January 16, 2007.

23. Please revise to clarify if the “draft letter of intent” included the consideration you would pay for the target.  If the draft letter included the consideration, please revise to discuss how the consideration changed, if any, as the draft letter was revised.

24. On page 56, we note the revised disclosure that you discussed the valuation with “Messrs. Wright and Richman.”  If the valuation was internal, please revise to discuss the reasons you would discuss such valuation with the target.

25. Please revise to indicate the subjects discussed at the December 12, 2006 meeting.

26. Please revise to briefly indicate the services provided by Mr. Kaufman.

27. We note the additional disclosure that BDR Research Group (BDR) provided

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
June 1, 2007 Page 6
you with a written report.  Please revise to discuss the material content of the report.

HAQ’s Reasons for the Merger and Recommendation of the HAQ Board, page 59

28. We note your statement that “Management of HAQ undertook a financial analysis of PharmAthene in order to determine that the value of the consideration to be issued by HAQ in connection with the Merger is fair and reasonable.”  Please revise to indicate, in this section, that the board of directors of HAQ determined that the consideration to be issued was fair from a financial point of view.

29. We note your prior statement that the HAQ Board of Directors determined that the consideration to be paid by HAQ is fair from a financial point of view.  We also you’re your revisions in this section in response to comment 41.  Please revise this section to specifically address how the Board of Directors of HAQ determined that the consideration was fair from a financial point of view.  Address in detail the specific valuations of PharmAthene performed which lead to the conclusion that the merger consideration to be paid by HAQ is fair from a financial point of view.  We may have further comment.

30. We note the revised disclosure on page 60 that you undertook a financial analysis of the target.  Please revise to provide more detail regarding that financial analysis performed.  In doing so, disclose the method(s) of analysis and the figures used in such analysis.  If projections or estimates were used, please provide the basis for such numbers.  Also clarify when the financial analysis took place.

31. We note the additional disclosure on page 60 that management also considered the value of the “intellectual property position.”  Please revise to discuss how management valued the “intellectual property position.”  In that regard, also clarify the meaning of the noted phrase.  Clarify how it is different than the value of the intellectual property itself.

32. On page 60, we note you disclose that you “recognized” historical valuations of “MPM Capital, HealthCare Ventures and Bear Stearns Health Innoventures.”  As management considered those valuations material to its determination of consideration, please revise to elaborate on those here.  Also, please revise to clarify if it is a generally accepted by the financial community to base a company’s value by its private placements.

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
June 1, 2007 Page 7
33. It is not clear how the “significant advances” by PharmAthene executives was considered as part of your valuation of the equity interest in PharmAthene.  Please revise to clarify.  Also, please clarify your use of the term “significant” in the noted disclosure.

34. We note the additional disclosure that “in each instance, HAQ management determined that the valuation for PharmAthene was, in fact equal or greater than the value of the consideration ascribed for PharmAthene.”  We also note disclosure in your initial proxy that you did not determine a value for the target.  Please revise to clarify when you made the determination in the noted disclosure on page 60.

35. We note the additional disclosure concerning the industry recognition you enjoy on page 60.  Please revise to disclose if you quantified this factor in determining the value of the target.

36. Revise your disclosure under Industry Presence to clarify that the contract with the Department of Defense for Protexia is for $35 million.

37. We note the disclosure concerning the valuation of comparable companies on page 61.  Please revise to fully discuss this analysis.  Identify the six companies deemed comparable and disclose their revenues, profits and market capitalization so that investors understand management’s considerations.

38. We note the disclosure of the government awarded contracts on page 61 as a reason for recommending the merger.  Please revise to clarify if those are funded or non-funded contracts.

39. We note the reference to the involvement of the target’s security holders on page 61 as a positive for this transaction.  Please revise to identify those security holders and discuss their involvement.

40. We note your response to comment 66.  We can not locate the discussion regarding PharmAthene’s business strategy in determining to recommend the merger.  Please advise or revise.

41. We note your response to comment 65 of our letter dated March 20, 2007 that you have discuss the aspect of the target’s financial results that the company considered on pages 60 and 61.  We are not able to locate such disclosure.  Please advise.

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
June 1, 2007 Page 8
Satisfaction of 80% requirement, page 61

42. Please revise to discuss in detail the analysis performed by the board of directors in determining that the fair market value of assets

CORRESP
1
filename1.htm

      Unassociated Document

        April
          20,
          2007

        VIA
          FEDERAL EXPRESS AND EDGAR

        United
          States Securities and Exchange Commission

        Office
          of
          Emerging Growth Companies

        100
          F
          Street, NE - Mail Stop 3561

        Washington,
          D.C. 20549

        Attn: Mr.
          Duc
          Dang

                  Re:

                  Healthcare
                    Acquisition Corp.

                  Preliminary
                    Proxy Statement

                  Filed
                    on February 9, 2007

                  File
                    No. 1-32587

        Ladies
          and Gentlemen:

        On
          behalf
          of Healthcare Acquisition Corp. (the “Company”
or
          “HAQ”), we are electronically transmitting hereunder of Amendment No. 1
          (“Amendment
          No. 1”)
          to the
          Preliminary Proxy Statement filed with the Securities and Exchange Commission
          (the “Commission”) on February 9, 2007 (the “Proxy
          Statement”)
          together with this letter which responds to the Staff’s comments to the
          Preliminary Proxy Statement set forth in a letter from John Reynolds, Assistant
          Director dated March 20, 2007, addressed to John Pappajohn, Chairman of
          the
          Board.

        We
          are
          authorized by the Company to provide the response contained in this letter
          on
          behalf of the Company. In this letter, we have recited the comments from
          the
          Staff in bold and have followed each comment with the Company’s response. Please
          note that the entire filing has been modified and updated to reflect the
          inclusion of financial statements for each of Healthcare Acquisition and
          PharmAthene, Inc.  at December 31, 2006.  Marked courtesy copies of
          this filing are being sent via overnight courier to Messrs. John Reynolds,
          Duc
          Dang and David Link.

        General

                1.

                  We
                    note
                    the
                    disclosure in the first risk factor on page 38 that your board
                    did not
                    determine a specific value for the target. Please revise your
                    letter and
                    notice to stockholders and summary section to highlight this
                    fact.
                    Further, in the appropriate section, please revise to clarify
                    how such
                    conduct is consistent with the disclosure in your IPO prospectus.
                    Clarify
                    how the board determined the merger to be fair, without determining
                    the
                    value of the target.

        We
          have
          revised the letter and notice to stockholders and summary section to clarify
          that the aggregate consideration being paid to the PharmAthene stockholders
          and
          noteholders is reflective of the price determined by the Board of Directors
          as
          the value of PharmAthene. We have revised the Preliminary Proxy Statement
          to
          clarify how such conduct is consistent with the disclosure in our IPO
          prospectus. Further, we have substantially modified and enhanced the Background
          of the Merger discussion and related topics at pages 51 through 59 to disclose
          the analytical bases for the Board’s reasons for the Merger with PharmAthene. We
          have cross referenced their discussions in the letter and notice to
          stockholders.

                2.

                  We
                    note the boldfaced disclosure in the forepart that shareholders
                    must
                    present their physical stock certificate on the business day
                    prior to the
                    date of the special meeting. On page 48, you disclose that shareholders
                    “will only be entitled to receive cash for these shares if you
                    continue to
                    hold these shares through the closing date of the merger and
                    then tender”
                    the certificate to you. The noted disclosures are not consistent.
                    Please
                    revise to reconcile your disclosure.

        We
          have
          revised this discussion to reflect that the shareholders who demand their
          portion of the trust fund have until 5:00 p.m. on the business day following
          closing of the merger to deliver their share certificates to the transfer
          agent.
          This modification removes, we believe, any confusion regarding the physical
          possession of the share certificates and voting rights (even though record
          holders as of the record date would retain all voting rights absent an
          agreement
          with a transferee otherwise). Please see page 46.

                3.

                  We
                    note the disclosure that tendering of the physical stock certificate,
                    please revise to clarify how shareholders will vote such shares
                    in the
                    special meeting if they no longer hold such shares, in street
                    name or
                    otherwise.

        Holders
          of record as of a record date are accorded voting rights under general
          corporate
          law (absent some agreement by the record holder to sell or transfer his
          voting
          rights) and physical possession of a share certificate is not required.
          However,
          as we have modified the discussion of the surrender of share certificates
          as
          outlined under our response to Comment 2 above, we believe that this issue
          has
          been resolved.

                  4.

                    In
                      connection with comment two, please revise to disclose the
                      rationale for
                      requiring the tendering before the meeting when the conversion
                      is
                      predicated on the merger getting approved, which may not occur.

        We
          have
          revised the Preliminary Proxy Statement to reconcile our disclosure and,
          therefore, we believe that this Comment is no longer applicable. Please see
          our response to Comment 2 above.

            2

                5.

                  In
                    connection with comment two, please revise in appropriate locations
                    to
                    clearly disclose the minimum amount of time that will be provided
                    to
                    shareholders to tender their shares for the conversion rights.
                    Clarify if
                    shareholders who tender their shares are still entitled to attend
                    the
                    meeting.

        We
          have
          revised the Preliminary Proxy Statement in appropriate locations to clearly
          disclose that shareholders will hold their shares until after closing of
          the
          Merger before they are required to tender their shares for the conversion
          rights. Please see page 48.

                6.

                  In
                    your disclosure discussing the conversion of shares, please revise
                    to
                    provide a step by step procedure, including the timing of the
                    tendering of
                    shares.

        We
          have
          revised the Preliminary Proxy Statement to provide a step by step procedure,
          including the timing of the tendering of shares for each conversion. Please
          see
          page 48.

                  7.

                    In
                      the appropriate sections, please revise to clearly discuss
                      the costs
                      associated with obtaining physical possession of the stock
                      certificates by
                      shareholders who hold their shares in street name. If possible,
                      in the
                      appropriate section, please revise to disclose the percentage
                      of your
                      shares that are held in street name.

        We
          have
          revised the Preliminary Proxy Statement to disclose that there may be costs
          associated with obtaining physical possession of the stock certificates
          by
          shareholders who hold their shares in street name. Based upon the Company’s
          discussion with its transfer agent and with general discussions with broker
          dealer firms, the costs are assessed by the broker dealer firm (or its
          clearing
          agent) and differ from firm to firm. Therefore, we cannot include a
          definitive cost in the discussion. Please see pages 5 and 48.

        We
          have
          also included disclosure regarding the percentage of our common stock held
          in street name.

        Proxy
          Card

                8.

                  Please
                    revise to highlight the entire sentence which indicates “If no direction
                    is made, this proxy will be voted “FOR” Proposals 1, 2 and 3”.

        We
          have
          revised the Proxy Card to highlight the entire sentence which indicates
“If no
          direction is made, this proxy will be voted “FOR” Proposals 1, 2, and 3. Please
          see the Proxy Card.

        Notice
          of Special Meeting of Stockholders

                  9.

                    In
                      the second paragraph after the caption “your vote is important” we note
                      the disclosure that you will not have sufficient time or resources
                      to find
                      another target should this one fail. We also note the disclosure
                      here and
                      elsewhere that you will commence the winding up, dissolution
                      and
                      liquidation “in accordance with the terms” of your certificate of
                      incorporation and the trust agreement. Instead, please revise
                      to disclose
                      the actual amount of time you will wait after a failure to
                      approve the
                      merger has taken place to initiate the winding up, dissolution
                      and
                      liquidation of your company.

            3

        We
          have
          revised the Preliminary Proxy Statement to disclose the actual amount of
          time
          that the Company will wait after a failure to approve the merger has taken
          place
          to initiate the winding up, dissolution and liquidation of the Company.
          The
          Company believes that it will be able to commence the dissolution process
          within
          5 business days of the vote, assuming the merger is not approved and has
          included such disclosure. Please see the Notice of Special Meeting of
          Stockholders.

                  10.

                    Also
                      here and in the appropriate section, please revise to clarify
                      what actions
                      you will take if a vote for dissolution is rejected.

        We
          have
          revised the Preliminary Proxy Statement to clarify that the Company will
          continue to seek approval of dissolution if a vote for dissolution is rejected,
          but that there can be no assurance that such approval would ever be obtained.
          Please see the Notice of Special Meeting of Stockholders and pages 41-43,
          63 and
          122.

        Summary
          of the Material Terms of the Merger, page 1

                11.

                  Please
                    revise to disclose the exchange ratio of your securities to those
                    of the
                    target.

        We
          have
          revised the Preliminary Proxy Statement to disclose the exchange ratio
          of the
          securities to those of the target. Please see pages 66-67. We also included
          the
          disclosure under the section regarding the terms of the merger at page
          1.

        Questions
          and Answers, page 2

                12.

                  In
                    question and answer 15 on page 5, we note that a “portion of the proceeds”
                    will be used to “finance the merger”. Please revise to clarify if that
                    means cash will be used as consideration for the merger or if
                    it
                    is
                    just being used to
                    pay expenses.

        We
          have
          revised the disclosure to clarify how the merger consideration is being
          paid and
          how expenses and conversion of shares are being paid. As disclosed in numerous
          sections of the Preliminary Proxy Statement, the actual merger consideration
          includes no cash other than the milestone payments, which are
          contingent and deferred underwriter costs, expenses related to the
          transaction and possible conversion of trust funds for shareholders so
          electing;
          substantially all of the amounts held in the trust fund, assuming the
          merger is completed, will be used for working capital of the post merger
          company. Please see page 9.

                13.

                  We
                    note the disclosure at the bottom of page five that you did not
                    obtain a
                    valuation or fairness opinion. Please revise to include a question
                    and
                    answer to clarify the value that your officers and directors
                    assigned to
                    the target and not just the fact that it exceeds 80% of your
                    net assets.

            4

        We
          have
          revised the disclosure to include a question and answer to clarify that
          the
          value that the management of the Company assigned to the target is based
          upon
          the purchase price as negotiated by the parties and not just the fact that
          it
          exceeds 80% of the net assets. As stated elsewhere in this letter, we have
          significantly modified the discussion of the Merger and submit that we
          have
          included disclosure which provides stockholders with a full discussion
          of the
          reasons for the Merger and valuation analysis of the Board. Please see
          pages 7
          and 60-61.

                    14.

                      We
                        note the inclusion of the public warrants to determine the
                        36.7% amount of
                        aggregate ownership by PharmAthene security holders. Since
                        you have
                        included the public warrants, please disclose the ownership
                        percentages
                        taking into account the possible conversion of the convertible
                        notes.

        We
          have
          revised the Preliminary Proxy Statement to disclose the ownership percentages
          taking into account the possible conversion of the convertible notes. Please

Mail Stop 3561

 May 20, 2007

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
2116 Financial Center
666 Walnut Street
Des Moines, Iowa 50309

 Re: Healthcare Acquisition Corp
  Preliminary Proxy Statement
  Filed on February 9, 2007
  File No. 1-32587

Dear Mr. Pappajohn:

We have reviewed your filing and have th e following comments.  Where indicated, we
think you should revise your document in response to these comments.  If you disagree, we will
consider your explanation as to why our commen t is inapplicable or a revision is unnecessary.
Please be as detailed as necessary  in your explanation.  In some of our comments, we may ask you
to provide us with supplemental information so we may better understand your disclosure.  After
reviewing this information, we may or  may not raise additional comments.

Please understand that the purpose of our review process is to  assist you in your compliance
with the applicable disclosure requirements and to enhance the ove rall disclosure in your filing.
We look forward to working with you in these re spects.  We welcome any questions you may have
about our comments or on any other aspect of our review.  Feel free to call us at the telephone
numbers listed at the end of this letter.

General

1. We note the disclosure in the first risk factor on page 38 that your board did not
determine a specific value fo r the target.  Please revi se your letter and notice to

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
March 20, 2007 Page 2
stockholders and summary section to highlight this fact.  Further,  in the appropriate
section, please revise to clarify how such conduct is consiste nt with the disclosure in
your IPO prospectus.  Clarify how the board de termined the merger to be fair, without
determining the value of the target.

2. We note the boldfaced disclosure in the forepa rt that shareholders must present their
physical stock certificate on the business day pr ior to the date of the special meeting.
On page 48, you disclose that shareholders “will only be entitled to receive cash for these shares if you continue to hold these shares through the closing date of the merger
and then tender” the certificate to you.  The noted disclosures are not  consistent.  Please
revise to reconcile  your disclosure.

3. We note the disclosure that te ndering of the physical stock ce rtificate, please revise to
clarify how shareholders will vote such shares  in the special meeting if they no longer
hold such shares, in street name or otherwise.

4. In connection with comment two, please revise to disclose the rationale for requiring the
tendering before the meeting when the convers ion is predicated on the merger getting
approved, which may not occur.

5. In connection with comment two, please revi se in appropriate lo cations to clearly
disclose the minimum amount of time that w ill provided to shareholders to tender their
shares for the conversion rights.  Clarify if shareholders who tender their shares are still
entitled to attend the meeting.

6. In your disclosure discussing the conversion of  shares, please revise to provide a step by
step procedure, including the timing of the tendering of shares.

7. In the appropriate sections, please revise to  clearly discuss the costs associated with
obtaining physical possession of the stock ce rtificates by shareholders who hold their
shares in street name.  If po ssible, in the appropriate sec tion, please revise to disclose
the percentage of your shares th at are held in street name.

Proxy Card

8. Please revise to highlight the entire senten ce which indicates “If no direction is made,
this proxy will be voted “FOR” Proposals 1, 2 and 3.

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
March 20, 2007 Page 3
Notice of Special Meeting of Stockholders

9. In the second paragraph af ter the caption “your vote is  important,” we note the
disclosure that you will not have sufficient time or resour ces to find another target
should this one fail.  We also note the di sclosure here and elsewhere that you will
commence the winding up, dissolution and liquida tion “in accordance with the terms” of
your certificate of inco rporation and the trust agreement.   Instead, please revise to
disclose the actual amount of time you will wait  after a failure to approve the merger has
taken place to initiate the winding up, di ssolution and liquidation of your company.

10. Also here and in the appropriate section, please revise to clarif y what actions you will
take if a vote for di ssolution is rejected.

Summary of the Material Terms of the Merger, page 1

11. Please revise to disclose the exchange ratio of your securities to those of the target.

Questions and Answers, page 2

12. In question and answer 15 on page 5, we note that a “portion of the proceeds” will be
used to “finance the merger.”  Please revise to clarify if that means cash will be used as
consideration for the merger or if it is  just being used to pay expenses.

13. We note the disclosure at the bottom of page five that you did not obtain a valuation or
fairness opinion.  Please revise to include a que stion and answer to cl arify the value that
your officers and directors assigned to the target  and not just the fact  that it exceeds 80%
of your net assets.

14. We note the inclusion of the public warra nts to determine the 36.7% amount of
aggregate ownership by PharmAthene security holders.  Since you have included the public warrants, please disclose the owne rship percentages taking into account the
possible conversion of the convertible notes.

15. Please revise to quantify the amount of cash th at will be issued in  lieu of fractional
shares when answering the second question on page six.

16. In answering question 25, please revise to  break down the post merger management
group to highlight who is currently asso ciated with you and with the target.

17. In response to question 26, please revise th e answer to quantify your current outstanding
liabilities and indicate the amount of thos e that are covered and not covered by waivers.

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
March 20, 2007 Page 4

Summary of the Proxy Statement, page 9

18. We note your statement that HAQ was formed to acquire “a business whose net assets
are at least 80% of the net assets of HAQ.”  Your Form S-1 stat ed that the business
combination must be for assets or with a ta rget business whose fair market value is at
least equal to 80% of our net assets at the time of such ac quisition.  Please revise as
appropriate.

19. Please revise to define your use of th e term “commercial stage” on page nine.

20. Please revise to clarify here that PharmAth ene has incurred losse s since inception, if
true.

21. Based on the disclosure on page 10 about the possible upward adjustment due to
conversions, please revise to disclose the maximum possible upward adjustment so that investors can understand the full possible exte nt of the dilution they could experience.

22. On page 10, we note that the preferred securities  of the target will be terminated.  Please
revise to clarify if the holders of such secu rities will receive anything in exchange due to
the terminations.

23. We note the disclosure on page 12 that holders of PharmAthene common stock may be entitled to dissenter’s or appraisal rights, however 80%  of the outstanding common
stock has voted in favor of the merger.  In the appropriate secti on, please revise to
clarify if PharmAthene’ security holders have  dissenter’s or apprai sal rights.  Also, in
the appropriate section, please revise to clarify if the Ph armAthene security holders
voted or consented to the merger.  Did the target hold a stockholders’ meeting?

24. In disclosing the interest of your directors and officers in the merger throughout this document, please revise to quantify the financia l interest they have in this transaction.
Quantify the total price they paid for their sh ares and the market price of such shares.
Also, disclose the total warra nts purchased and the paid and current price of such
warrants.  If there are any arrangements cont emplated for your initial shareholders to act
as consultants or any other role, please disclose also.

25. We note that the beneficial ownership ta ble on page 13 does not include common stock
issuable upon the exercise of warrants when the warrants are exercisable upon the
consummation of the business combination.  Advise us of the legal basis why the
warrants are not included in the beneficial ownership table.

26. Please revise to indicate the control pers ons for Sapling, LLC and Fir Tree Recovery
Master Fund, LP.

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
March 20, 2007 Page 5
27. Please fill in the table at the top of page 15.

28. Please revise to fill in the percentage bla nks under the caption “interest of PharmAthene
directors and officers in  the merger” on page 15.

Selected Historical Fina ncial Information, page 19

29. Revise your table of operati ng results included at page 19 to indicate PharmAthene’s
results for the nine months ended September 30, 2006 are unaudited.

Market Price Information, page 23

30. On this page, please revise to  highlight the current market price and how it compares to
the conversion price.

Risk Factors, page 24

31. As they are currently written, your risk factor subheadings only highlight facts and not
the risks associated with the materialization of the facts.  Please re vise your subheadings
to highlight the risk and harm to be suffe red should the disclosed facts materialize.

32. Please revise risk factor two to briefly discuss the risk you are attempting to convey and
include more detailed disclosure later in the document if material.

33. Risk factors six and seven appear to address the same risk.  Please revise to clarify how
they are separate risks.

34. Risk factor five addressing the expensive and uncertain development process appears very similar to risk factor nine addressing delays in clinical trials and development cost.  Please revise to clarify how they are separate risks.

35. Risk factor 15, the risk associat ed with retention of personnel,  appears to be a risk that
affects companies in and outside of your indus try.  Please revise to clarify how the risk
is specific to you.

36. Risk factor 16, the risk associated with “managing growth” is a risk that affects companies in and outside of your industry.  In addition the risk factor  appears generic.
Please revise to clarify how the risk is specific to you.

37. In risk factor 17, please revi se to disclose the number of patents you rely upon and the
ownership of such patents.

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
March 20, 2007 Page 6

38. Your risk factors 17 and 19 app ear to address similar risks.  Please revise to combine the
relevant portions of these fact ors into a single risk factor.

39. The risk factors need to be set forth in the order of materiality.  In  this regard, you must
more prominently disclose that there was no independent valuation of PharmAthene undertaken in connectio n with the Merger.

40. In the risk factor on page 39, please revise to quantify the total amount of liabilities
outstanding.  Also identify the entities which have not waived their rights, interests or
claims to the funds held in the trust account.

The HAQ Special Meeting of  Stockholders, page 45

41. We note your statement that “the HAQ Board of Directors … has determined that the
consideration to be paid by HAQ in connect ion with the Merger is fair … from a
financial point of view and the fair market value of PharmAthene is equal to or greater
than 80% of the value of th e net assets of HAQ.”   We also note your statement that
HAQ did not determine a specific valuation of  PharmAthene at the time it entered into
the merger agreement.  Revise to specifica lly address how the Board of Director of
HAQ determined that the consideration was fair from a financial point of view when it did not determine a specific valuation of Phar mAthene when it entered into the merger
agreement.  We may have further comment.

Solicitation Costs, page 48

42. We note that directors and officers of H ealthcare Acquisition may call or personally
solicit proxies from the stockholde rs.  You must file any script s, outlines, instructions or
other written materials you will furnish to individuals soliciting proxies.  You must also file materials furnished to assist in the answ ering of stockholder inquir ies.  Refer to Rule
14a-6(c) of Regulation 14A.

The Merger Proposal, page 50

43. Briefly indicate the amount of additional shares which maybe issued if the maximum
numbers of shareholders exer cise their conversion rights.

Background of the Merger, page 50

44. Please revise to address the criteria used in your search for target companies.

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
March 20, 2007 Page 7
45. Please indicate the time frame of your di scussions with the 10 potential target
companies.  Revise to provide a detailed time line concerning Healthcare’s contacts
with prospective targets.

46. Please revise to address in more detail the ne gotiations with the target that resulted in a
signed letter of intent.  Briefly describe th e business conducted by the target that signed
the letter of intent.  Address the reasons w hy an agreement with that target was not
reached.

47. Briefly describe the business c onducted by SIGA Acquisition Corp.

48. Revise to address the reasons why the merger agreement was terminated by SIGA Acquisition Corp.

49. Please revise to disclose the purchase pric e Siga was going to pay for PharmAthene and
compare it to the consideration to be  offered in this transaction.

50. We note that counsel to PharmAthene serv es as counsel to a company on which John
Pappajohn and Derace Schaffer, MD serv e as directors and of which Wayne
Schellhammer is President and CEO.  Please revise to clarify whether there were any
discussions between counsel to PharmAth ene and John Pappajohn, Derace Schaffer or
Wayne Schellhammer prior to October 5, 2006 concerning the acquisition of
PharmAthene by Healthcare Acquisition.

51. Describe, in greater detail , discussions during the peri od between October 5, 2006 and
January 16, 2007.  Discuss each meeting in de tail.  Describe the substance of all
material discussions.

52. In this section, please revise to highli ght the 18 month deadline by which you were
required to at least locate a target.

53. Discuss the negotiations of the merger in greater deta il.  Clarify how the final
consideration was determined.  Discuss wh ether any valuation of PharmAthene was
conducted prior to or during the merger negotia tions.  Indicate whet her any valuation of
PharmAthene was presented to the Healthcare board of directors prior to their approval
of the merger on January 16, 2007.  Discu ss whether and/or how The Maxim Group
participated in determining the consideration to be paid to PharmAthene.

54. Please clarify when The Maxim Group was retained to assist on the merger transaction.  Indicate the services  performed by The Maxim Group in connection with the merger
negotiations.
55. Any presentations or reports prepared by ma nagement or The Maxim Group, prior to the
board’s determination on January 16, 2007 to approve the merger, should be described

Mr. John Pappajohn, Chairman of the Board
Healthcare Acquisition Corp
March 20, 2007 Page 8
in reasonable detail, by date, indicating th e nature of the presentation, information
presented, recommendations and conclusions .  Any materials, including reports,
analyses, projections, talking pa pers and similar items which were prepared or presented
at the board meetings should be supplementa lly provided to the staff.  The disclosure
should not be conclusory and should

<DOCUMENT>
<TYPE>LETTER
<SEQUENCE>1
<FILENAME>filename1.txt
<TEXT>

MAIL STOP 3561

								July 25, 2005

Matthew P. Kinley
President
Healthcare Acquisition Corp.
2116 Financial Center
666 Walnut Street
Des Moines, Iowa  50309

RE:	Healthcare Acquisition Corp.
	Registration Statement on Form S-1
	File No. 333-124712
Amendment No. 2 Filed July 12, 2005

Dear Mr. Kinley:

      We have reviewed your filing and have the following
comments.
Where indicated, we think you should revise your document in
response
to these comments.  If you disagree, we will consider your
explanation as to why our comment is inapplicable or a revision is
unnecessary.  Please be as detailed as necessary in your
explanation.
In some of our comments, we may ask you to provide us with
supplemental information so we may better understand your
disclosure.
After reviewing this information, we may or may not raise
additional
comments.

      Please understand that the purpose of our review process is
to
assist you in your compliance with the applicable disclosure
requirements and to enhance the overall disclosure in your filing.
We look forward to working with you in these respects.  We welcome
any questions you may have about our comments or on any other
aspect
of our review.  Feel free to call us at the telephone numbers
listed
at the end of this letter.

Commitments and Contingencies, page F-10

1. We have reviewed your response to our prior comment 7 regarding
the underwriter purchase option and believe that Note 7 to the
financial statements should be expanded to disclose the major
assumptions used by management in determining fair value.  We note
management`s conclusion, as disclosed on page F-8, that the option
had no value at April 30, 2005.  In regards to the assumptions, we
believe that a volatility assumption should be used that is in
accordance with the principle outlined in paragraph 23 of FAS
123R,
and that the use of a minimum value method would not be
appropriate.
Please clarify in the notes to the financial statements the
expected
timing for issuance of the purchase option in relation to
effectiveness of the registration statement and sale of the stock
and
warrants.  Please indicate whether the purchase option will be
issued
in the event that the Form S-1 is not declared effective.  We note
that the purchase option is expected to be effective for the
interval, from the later of the consummation of a business
combination or one year from the date of the prospectus, to its
expiration in five years.  As applicable, please expand MD&A to
discuss the transaction and the likely future effect on your
financial condition and results of operations.

Exhibit 23.1

2. The accountants consent should be revised to refer to their
dual
dated report of May 6 and July 8, 2005.

Closing Comments

      As appropriate, please amend your registration statement in
response to these comments.  You may wish to provide us with
marked
copies of the amendment to expedite our review.  Please furnish a
cover letter with your amendment that keys your responses to our
comments and provides any requested supplemental information.
Detailed cover letters greatly facilitate our review.  Please
understand that we may have additional comments after reviewing
your
amendment and responses to our comments.

      We direct your attention to Rules 460 and 461 regarding
requesting acceleration of a registration statement.  Please allow
adequate time after the filing of any amendment for further review
before submitting a request for acceleration.  Please provide this
request at least two business days in advance of the requested
effective date.

You may contact Maureen Bauer at (202) 551-3237 if you have
questions
regarding comments on the financial statements and related
matters.
Questions on other disclosure issues may be directed to John Zitko
at
(202) 551-3399.

      Sincerely,

John Reynolds
Assistant Director

cc: 	Stuart Neuhaser (by facsimile)
      	(212) 370-7889
??

??

??

??

Matthew P. Kinley
Healthcare Acquisition Corp.
July 25, 2005
Page 1

</TEXT>
</DOCUMENT>

<DOCUMENT>
<TYPE>CORRESP
<SEQUENCE>1
<FILENAME>filename1.txt
<TEXT>
<PAGE>

                         ELLENOFF GROSSMAN & SCHOLE LLP
                                370 Lexington Ave
                               New York, NY 10017
                            Telephone: (212) 370-1300
                               Fax: (212) 370-7889

                                                                   July 28, 2004

VIA FACSIMILE

United States Securities and Exchange Commission
Mail Stop 3561
Washington, D.C. 20549

Attn:    John Reynolds
         Assistant Director

Re:      HEALTHCARE ACQUISITION CORP.
         AMERICAN STOCK EXCHANGE LISTING STANDARDS
         SEC FILE NO. 333-124712

Dear Sir:

         On behalf of Healthcare Acquisition Corp., a Delaware corporation (the
"REGISTRANT") we hereby notify you that the American Stock Exchange has notified
the Registrant that it has met Initial Listing Standards 3 and 4 of the American
Stock Exchange Company Guide, to wit:

INITIAL LISTING STANDARD 3

         Size:
         Stockholders' equity of at least $4,000,000.

         THE REGISTRANT WILL HAVE A POST OFFERING STOCKHOLDERS' EQUITY OF
         $53,592,998.

         Total Value of Market Capitalization:
         $50,000,000.

         THE REGISTRANT WILL HAVE A POST OFFERING TOTAL MARKET CAPITALIZATION OF
         $90,000,000.

         Aggregate Market Value of Publicly Held Shares:
         $15,000,000.

         THE REGISTRANT'S PUBLICLY-HELD SECURITIES WILL HAVE $72,000,000 OF
         AGGREGATE MARKET VALUE, POST OFFERING.

         Distribution:
         Minimum public distribution of 500,000 shares, together with a minimum
         of 800 public shareholders or minimum public distribution of 1,000,000
         shares together with a minimum of 400 public shareholders.
<PAGE>

         PLEASE SEE RESPONSE CONTAINED IN THE LAST PARAGRAPH OF THIS LETTER.

INITIAL LISTING STANDARD 4

         Total Value of Market Capitalization:
         $75,000,000.

         THE REGISTRANT WILL HAVE A POST OFFERING TOTAL MARKET CAPITALIZATION OF
         $90,000,000.

         Aggregate Market Value of Publicly Held Shares:
         $20,000,000.

         THE REGISTRANT'S PUBLICLY-HELD SECURITIES WILL HAVE $72,000,000 OF
         AGGREGATE MARKET VALUE, POST OFFERING.

         Distribution:
         Minimum public distribution of 500,000 shares, together with a minimum
         of 800 public shareholders or minimum public distribution of 1,000,000
         shares together with a minimum of 400 public shareholders.

         With respect to the "Distribution" criteria of standards 3 and 4 above,
please note that the American Stock Exchange has been advised by the
representative of the underwriters in this offering, Maxim Group LLC, that the
distribution requirement of a minimum public distribution of 1,000,000 shares
together with a minimum of 400 public shareholders will be satisfied or
exceeded. The representative of the underwriters stated that it was confident
that such criteria could be met using its own retail sales offices and the
institutional departments of the underwriting syndicate being organized (which
includes approximately 3-7 firms to underwrite and distribute the offering). In
fact, the representative of the underwriters has advised this firm that there
are currently more than 1,100 accounts on their "indications of interest" list.
Please note further that Maxim Group LLC has agreed to provide written notice to
the American Stock Exchange within five days of the commencement of trading that
this requirement has been satisfied.

         If you have any questions, please feel free to contact me at your
earliest convenience.

                                                          Very truly yours,

                                                          /s/ Stuart Neuhauser
                                                          --------------------
                                                          Stuart Neuhauser

cc:      Mr. Matthew P. Kinley
         Steven Skolnick, Esq.

</TEXT>
</DOCUMENT>

<DOCUMENT>
<TYPE>CORRESP
<SEQUENCE>1
<FILENAME>filename1.txt
<TEXT>
<PAGE>

                                 MAXIM GROUP LLC
                              405 LEXINGTON AVENUE
                            NEW YORK, NEW YORK 10174

                                  July 26, 2005

Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C.  20549

         RE:      HEALTHCARE ACQUISITION CORP. (THE "COMPANY")
                  REGISTRATION STATEMENT ON FORM S-1 (FILE NO. 333-124712)
                  --------------------------------------------------------

Ladies and Gentlemen:

         In connection with the above-captioned registration statement, and
pursuant to Rule 461 under the Securities Act of 1933, as amended (the "Act"),
the undersigned, as representative of the underwriters, hereby joins in the
request of the Company that the effective date of such registration statement be
accelerated to 4:30 p.m. (NYT) on Thursday, July 28, 2005, or as soon thereafter
as practicable.

         In accordance with Rule 460 under the Act and in connection with the
foregoing, please note that the undersigned have effected from July 12, 2005
through the date hereof approximately the following distribution of:

         Preliminary Prospectus dated July 12, 2005

         6,200 copies to prospective institutional investors, dealers and others

         Preliminary Prospectus dated July 25, 2005

         3,200 copies to prospective institutional investors, dealers and others

<PAGE>

         The undersigned confirms that it has complied with and will continue to
comply with, and it has been informed or will be informed by participating
dealers that they have complied with or will comply with, Rule 15c2-8 under the
Securities Exchange Act of 1934, as amended, in connection with the
above-referenced issue.

                                      Very  truly yours,

                                      MAXIM GROUP LLC, as representative
                                               of the underwriters

                                      By: /s/ Cliff Teller
                                          -------------------------------------

</TEXT>
</DOCUMENT>

<DOCUMENT>
<TYPE>CORRESP
<SEQUENCE>1
<FILENAME>filename1.txt
<TEXT>
<PAGE>

                          HEALTHCARE ACQUISITION CORP.
                              2116 FINANCIAL CENTER
                                666 WALNUT STREET
                             DES MOINES, IOWA 50309

                                                              July 26, 2005

VIA EDGAR AND FACSIMILE
-----------------------

United States Securities and Exchange Commission
Mail Stop 3561
Washington, D.C. 20549

Attn: John Reynolds
      Assistant Director

Re:   HEALTHCARE ACQUISITION CORP.
      REGISTRATION STATEMENT ON FORM S-1 FILED MAY 6, 2005
      AMENDMENT NO. 1 TO REGISTRATION STATEMENT ON FORM S-1 FILED JUNE 9, 2005
      AMENDMENT NO. 2 TO REGISTRATION STATEMENT ON FORM S-1 FILED JULY 12, 2005
      AMENDMENT NO. 3 TO REGISTRATION STATEMENT ON FORM S-1 FILED JULY 25, 2005
      FILE NO. 333-124712
      -------------------------------------------------------------------------

Dear Sir:

         Pursuant to Rule 461 under the Securities Act of 1933, the Registrant
hereby requests acceleration of effectiveness of its Registration Statement so
that it will become effective at 4:30 P.M. on July 28, 2005 or as soon as
thereafter practicable.

         Please note that we acknowledge the following:

         should the Securities and Exchange Commission (the "Commission") or the
         staff, acting pursuant to delegated authority, declare the filing
         effective, it does not foreclose the Commission from taking any action
         with respect to the filing;

         the action of the Commission or the staff, acting pursuant to delegated
         authority, in declaring the filing effective, does not relieve the
         company from its full responsibility for the adequacy and accuracy of
         the disclosure in the filing; and

         the company may not assert staff comments and the declaration of
         effectiveness as a defense in any proceeding initiated by the
         Commission or any person under the federal securities laws of the
         United States.

<PAGE>

         If you have any questions or comments, please feel free to contact me
at your earliest convenience.

                                                       Very truly yours,

                                                       /s/ Matthew P. Kinley
                                                       ---------------------
                                                       Matthew P. Kinley
                                                       President

cc: Stuart Neuhauser, Esq.
    Steven Skolnick, Esq.
</TEXT>
</DOCUMENT>

<DOCUMENT>
<TYPE>CORRESP
<SEQUENCE>1
<FILENAME>filename1.txt
<TEXT>
<PAGE>

                          HEALTHCARE ACQUISITION CORP.
                              2116 FINANCIAL CENTER
                                666 WALNUT STREET
                             DES MOINES, IOWA 50309

                                                              July 26, 2004

VIA EDGAR AND FACSIMILE

United States Securities and Exchange Commission
Mail Stop 3561
Washington, D.C. 20549

Attn:    John Reynolds
         Assistant Director

Re:      HEALTHCARE ACQUISITION CORP. (THE "REGISTRANT")
         REGISTRATION STATEMENT ON FORM S-1, AS AMENDED
         SEC FILE NO. 333-124712

Dear Sir:

         Pursuant to Rule 461 under the Securities Act of 1933, as amended, the
Registrant hereby requests acceleration of effectiveness of the above-referenced
Registration Statement so that it will become effective at 4:30 P.M. on
Thursday, July 28, 2005, or as soon as thereafter practicable.

                                                     Very truly yours,

                                                     /s/ Matthew P. Kinley
                                                     ---------------------
                                                     Matthew P. Kinley
                                                     President

cc:      Stuart Neuhauser, Esq.

</TEXT>
</DOCUMENT>