SecProbe.io

CORRESP
 1
 filename1.htm

 PHIO PHARMACEUTICALS CORP.

 411 Swedeland Road, Suite 23-1080

 King of Prussia, PA 19406

 December 1, 2025

 VIA EDGAR

 Office of Life Sciences

 Division of Corporation Finance

 U.S. Securities and Exchange Commission

 100 F Street, N.E.

 Washington, D.C. 20549

 Attn: Alan Campbell

 Re: Phio Pharmaceuticals Corp.

 Registration Statement on Form S-3

 Filed November 20, 2025

 File No. 333-291667

 Request for Acceleration of Effective Date

 Dear Mr. Campbell:

 Pursuant to Rule 461 of the
General Rules and Regulations under the Securities Act of 1933, as amended, Phio Pharmaceuticals Corp. hereby requests that the Securities
and Exchange Commission accelerate the effective date of the above-referenced Registration Statement on Form S-3 and declare such Registration
Statement effective as of 4:00 p.m., Eastern Time, on December 3, 2025, or as soon thereafter as possible.

 Please direct any questions
or comments concerning this request to Lisa Carson of Phio Pharmaceuticals Corp. at (610) 310-1726. Also, please notify Ms. Carson when
this request for acceleration has been granted.

 Very truly yours,

 PHIO PHARMACEUTICALS CORP.

 By: /s/ Robert J. Bitterman

 Name: Robert
J. Bitterman

 Title: President and Chief Executive
Officer

 cc: Lisa Carson, Phio Pharmaceuticals
Corp.

CORRESP
 1
 filename1.htm

 PHIO PHARMACEUTICALS CORP.

 411 Swedeland Road, Suite 23-1080

 King of Prussia, PA 19406

 August 21, 2025

 VIA EDGAR

 Office of Life Sciences

 Division of Corporation Finance

 U.S. Securities and Exchange Commission

 100 F Street, N.E.

 Washington, D.C. 20549

 Attn: Jessica Dickerson

 Re:
 Phio Pharmaceuticals Corp.

 Registration Statement on Form S-3

 Filed August 15, 2025

 File No. 333-289621

 Request for Acceleration of Effective Date

 Dear Ms. Dickerson:

 Pursuant to Rule 461 of the
General Rules and Regulations under the Securities Act of 1933, as amended, Phio Pharmaceuticals Corp. hereby requests that the Securities
and Exchange Commission accelerate the effective date of the above-referenced Registration Statement on Form S-3 and declare such Registration
Statement effective as of 4:00 p.m., Eastern Time, on August 22, 2025, or as soon thereafter as possible.

 Please direct any questions
or comments concerning this request to Amanda Brown of Hogan Lovells US LLP at (267) 675-4683. Also, please notify Ms. Brown when this
request for acceleration has been granted.

 Very truly yours,

 PHIO PHARMACEUTICALS CORP.

 By: /s/ Robert J. Bitterman

 Name: Robert
J. Bitterman

 Title: President and Chief Executive
Officer

 cc: Amanda Brown, Hogan Lovells US LLP

<DOCUMENT>
<TYPE>TEXT-EXTRACT
<SEQUENCE>2
<FILENAME>filename2.txt
<TEXT>
 August 21, 2025

Robert Bitterman
Chief Executive Officer
Phio Pharmaceuticals Corp.
411 Swedeland Road, Suite 23-1080
King of Prussia, PA 19406

 Re: Phio Pharmaceuticals Corp.
 Registration Statement on Form S-3
 Filed August 15, 2025
 File No. 333-289621
Dear Robert Bitterman:

 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 Jessica Dickerson at 202-551-8013 with any questions.

 Sincerely,

 Division of
Corporation Finance
 Office of Life
Sciences
cc: Steven J. Abrams, Esq.
</TEXT>
</DOCUMENT>

CORRESP
1
filename1.htm

PHIO PHARMACEUTICALS CORP.

11 Apex Drive, Suite 300A, PMB 2006

Marlborough, MA 01752

January 27, 2025

VIA EDGAR

Office of Life Sciences

Division of Corporation Finance

U.S. Securities and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549

Attn: Tamika Sheppard

  Re:
  Phio Pharmaceuticals Corp.

  Registration Statement on Form S-1

  Filed January 21, 2025

  File No. 333-284381

  Request for Acceleration of Effective Date

Dear Ms. Sheppard:

Pursuant to Rule 461 of the
General Rules and Regulations under the Securities Act of 1933, as amended, Phio Pharmaceuticals Corp. hereby requests that the Securities
and Exchange Commission accelerate the effective date of the above-referenced Registration Statement on Form S-1 and declare such Registration
Statement effective as of 4:00 p.m., Eastern Time, on January 28, 2025, or as soon thereafter as possible.

Please direct any questions
or comments concerning this request to Amanda Brown of Hogan Lovells US LLP at (267) 675-4683. Also, please notify Ms. Brown when this
request for acceleration has been granted.

    Very truly yours,

    PHIO PHARMACEUTICALS CORP.

    By:
    /s/ Robert J. Bitterman

    Name:

Title:
    Robert J. Bitterman
President and Chief Executive Officer

cc: Amanda
Brown, Hogan Lovells US LLP

January 24, 2025
Robert Bitterman
Chief Executive Officer
Phio Pharmaceuticals Corp.
11 Apex Drive, Suite 300A, PMB 2006
Marlborough, Massachusetts 01752
Re:Phio Pharmaceuticals Corp.
Registration Statement on Form S-1
Filed January 21, 2025
File No. 333-284381
Dear Robert Bitterman:
            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 Tamika Sheppard at 202-551-8346 with any questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:Amanda Brown, Esq.

CORRESP
1
filename1.htm

PHIO PHARMACEUTICALS CORP.

11 Apex Drive, Suite 300A, PMB 2006

Marlborough, MA 01752

July 30, 2024

VIA EDGAR

Office of Life Sciences

Division of Corporation Finance

U.S. Securities and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549

Attn: Tim Buchmiller

  Re:
  Phio Pharmaceuticals Corp.

  Registration Statement on Form S-1

Filed
July 26, 2024

  File No. 333-281052

  Request for Acceleration of Effective Date

Dear Mr. Buchmiller:

Pursuant to Rule 461 of the General Rules and Regulations
under the Securities Act of 1933, as amended, Phio Pharmaceuticals Corp. hereby requests that the Securities and Exchange Commission accelerate
the effective date of the above-referenced Registration Statement on Form S-1 and declare such Registration Statement effective as of
4:00 p.m., Eastern Time, on August 1, 2024, or as soon thereafter as possible.

Please direct any questions or comments concerning
this request to Amanda Brown of Hogan Lovells US LLP at (267) 675-4683. Also, please notify Ms. Brown when this request for acceleration
has been granted.

  Very truly yours,

  PHIO PHARMACEUTICALS CORP.

  By: /s/ Robert J. Bitterman

  Name:
  Robert
J. Bitterman

  Title:
  President and Chief Executive
Officer

cc: Amanda Brown, Hogan Lovells US LLP

July 29, 2024
Robert J. Bitterman
President and Chief Executive Officer
Phio Pharmaceuticals Corp.
11 Apex Drive, Suite 300A, PMB 2006
Marlborough, Massachusetts 01752
Re:Phio Pharmaceuticals Corp.
Registration Statement on Form S-1
Filed July 26, 2024
File No. 333-281052
Dear Robert J. Bitterman:
            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 Tim Buchmiller at 202-551-3635 with any questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:Steven J. Abrams, Esq.

CORRESP
1
filename1.htm

PHIO PHARMACEUTICALS CORP.

11 Apex Drive, Suite 300A, PMB 2006

Marlborough, MA 01752

June 27, 2024

VIA EDGAR

Office of Life Sciences

Division of Corporation Finance

U.S. Securities and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549

Attn: Tamika Sheppard

Re: Phio Pharmaceuticals Corp.

  Registration Statement on Form S-3

  Filed May 20, 2024

  File No. 333-279557

  Request for Acceleration of Effective Date

Dear Ms. Sheppard:

Pursuant to Rule 461 of the General Rules and Regulations
under the Securities Act of 1933, as amended, Phio Pharmaceuticals Corp. hereby requests that the Securities and Exchange Commission accelerate
the effective date of the above-referenced Registration Statement on Form S-3 and declare such Registration Statement effective as of
4:00 p.m., Eastern Time, on July 1, 2024, or as soon thereafter as possible.

Please direct any questions or comments concerning
this request to Brandon Kinnard of Hogan Lovells US LLP at (303) 454-2477. Also, please notify Mr. Kinnard when this request for acceleration
has been granted.

    Very truly yours,

    PHIO PHARMACEUTICALS CORP.

    By:
    /s/ Robert J. Bitterman

    Name:

        Title:

    Robert J. Bitterman
President and Chief Financial Officer

cc: Brandon Kinnard, Hogan Lovells US
LLP

United States securities and exchange commission logo
May 24, 2024
Caitlin Kontulis
Vice President, Finance and Administration
Phio Pharmaceuticals Corp.
11 Apex Drive, Suite 300A, PMB 2006
Marlborough, MA 01752
Re:Phio Pharmaceuticals Corp.
Registration Statement on Form S-3
Filed May 20, 2024
File No. 333-279557
Dear Caitlin Kontulis:
            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 Tamika Sheppard at 202-551-8346 with any questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:       Steve Abrams

CORRESP
1
filename1.htm

PHIO PHARMACEUTICALS CORP.

257 Simarano Drive, Suite 101

Marlborough, MA 01752

December 22, 2023

VIA EDGAR

Office of Life Sciences

Division of Corporation Finance

U.S. Securities and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549

Attn: Daniel Crawford

  Re:
  Phio Pharmaceuticals Corp.

  Registration Statement on Form S-1

  Filed December 19, 2023

  File No. 333-276146

  Request for Acceleration of Effective Date

Dear Mr. Crawford:

Pursuant to Rule 461 of the General Rules and Regulations
under the Securities Act of 1933, as amended, Phio Pharmaceuticals Corp. hereby requests that the Securities and Exchange Commission accelerate
the effective date of the above-referenced Registration Statement on Form S-1 and declare such Registration Statement effective as of
4:00 p.m., Eastern Time, on December 27, 2023, or as soon thereafter as possible.

Please direct any questions or comments concerning
this request to Brandon Kinnard of Hogan Lovells US LLP at (303) 454-2477. Also, please notify Mr. Kinnard when this request for acceleration
has been granted.

  Very truly yours,

  PHIO PHARMACEUTICALS CORP.

  By:
  /s/ Robert J. Bitterman

  Name:
  Robert
J. Bitterman

  Title:
  President and Chief Financial
Officer

United States securities and exchange commission logo
December 21, 2023
Robert Bitterman
President & CEO
Phio Pharmaceuticals Corp.
257 Simarano Drive, Suite 101
Marlborough, MA 01752
Re:Phio Pharmaceuticals Corp.
Registration Statement on Form S-1
Filed December 19, 2023
File No. 333-276146
Dear Robert Bitterman:
            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 Daniel Crawford at 202-551-7767 with any questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:       Brandon Kinnard, Esq.

CORRESP
1
filename1.htm

PHIO PHARMACEUTICALS CORP.

257 Simarano Drive, Suite 101

Marlborough, MA 01752

June 14, 2023

VIA EDGAR

Office of Life Sciences

Division of Corporation Finance

U.S. Securities and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549

Attn: Tyler Howes

  Re:
  Phio Pharmaceuticals Corp.

  Registration Statement on Form S-1

  Filed June 8, 2023

  File No. 333-272526

  Request for Acceleration of Effective Date

Dear Mr. Howes:

Pursuant to Rule 461 of the General Rules and Regulations
under the Securities Act of 1933, as amended, Phio Pharmaceuticals Corp. hereby requests that the Securities and Exchange Commission accelerate
the effective date of the above-referenced Registration Statement on Form S-1 and declare such Registration Statement effective as of
5:00 p.m., Eastern Time, on June 16, 2023, or as soon thereafter as possible.

Please direct any questions or comments concerning
this request to Steven Abrams of Hogan Lovells US LLP at (267) 675-4671. Also, please notify Mr. Abrams when this request for acceleration
has been granted.

    Very truly yours,

    PHIO PHARMACEUTICALS CORP.

    By:
    /s/ Robert
J. Bitterman

    Name: Robert
J. Bitterman
Title: President and Chief Financial
Officer

United States securities and exchange commission logo
June 14, 2023
Robert Bitterman
Chief Executive Officer
Phio Pharmaceuticals Corp.
257 Simarano Drive, Suite 101
Marlborough, Massachusetts 01752
Re:Phio Pharmaceuticals Corp.
Registration Statement on Form S-1
Filed June 8, 2023
File No. 333-272526
Dear Robert Bitterman:
            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:       Steven J. Abrams, Esq.

United States securities and exchange commission logo
May 5, 2023
Robert Bitterman
Chief Executive Officer
Phio Pharmaceuticals Corp.
257 Simarano Drive, Suite 101
Marlborough, MA 01752
Re:Phio Pharmaceuticals Corp.
Registration Statement on Form S-1
Filed April 28, 2023
File No. 333-271521
Dear Robert Bitterman:
            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 Doris Stacey Gama at 202-551-3188 with any questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:       Steven Abrams, Esq.

CORRESP
1
filename1.htm

PHIO PHARMACEUTICALS CORP.

257 Simarano Drive, Suite 101

Marlborough, MA 01752

May 5, 2023

VIA EDGAR

Office of Life Sciences

Division of Corporation Finance

U.S. Securities and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549

Attn: Doris Stacey Gama

  Re:
  Phio Pharmaceuticals Corp.

  Registration Statement on Form S-1

  Filed April 28, 2023

File No.
333-271521

  Request for Acceleration of Effective Date

Dear Ms. Gama:

Pursuant to Rule 461 of the General Rules and Regulations
under the Securities Act of 1933, as amended, Phio Pharmaceuticals Corp. hereby requests that the Securities and Exchange Commission accelerate
the effective date of the above-referenced Registration Statement on Form S-1 and declare such Registration Statement effective as of
4:00 p.m., Eastern Time, on May 9, 2023, or as soon thereafter as possible.

Please direct any questions or comments concerning
this request to Steven Abrams of Hogan Lovells US LLP at (267) 675-4671. Also, please notify Mr. Abrams when this request for acceleration
has been granted.

  Very truly yours,

  PHIO PHARMACEUTICALS CORP.

  By:
  /s/ Robert J. Bitterman

  Name:
  Robert
J. Bitterman

  Title:
  President and Chief Executive
Officer

CORRESP
1
filename1.htm

Phio Pharmaceuticals
Corp.

257 Simarano Drive, Suite 101 | Marlborough, MA
01752

May 19, 2021

VIA EDGAR

Securities and Exchange Commission

Division of Corporation Finance

100 F Street, N.E.

Washington, DC 20549

 Attn: Jeff Gabor

 Re: Phio Pharmaceuticals Corp.

    Registration Statement on Form S-3 (File No.
                                            333-256100)

Ladies and Gentlemen:

Pursuant to Rule 461 under the Securities Act of
1933, as amended, Phio Pharmaceuticals Corp. (the “Company”) hereby respectfully requests that the effective
date of the above-referenced registration statement on Form S-3 filed by the Company (the “Registration Statement”)
be accelerated so that it will be declared effective at 5:00 p.m., Eastern Time, on May 21, 2021, or as soon thereafter as practicable.

  Very truly yours,

  PHIO PHARMACEUTICALS CORP.

  /s/ Gerrit Dispersyn

  Gerrit Dispersyn, Dr. Med. Sc.

  President and Chief Executive Officer

cc: Ryan A. Murr, Gibson, Dunn & Crutcher LLP

United States securities and exchange commission logo
May 19, 2021
Gerrit Dispersyn, Dr. Med. Sc
President and Chief Executive Officer
Phio Pharmaceuticals Corp.
257 Simarano Drive, Suite 101
Marlborough, MA 01752
Re:Phio Pharmaceuticals Corp.
Registration Statement on Form S-3
Filed May 13, 2021
File No. 333-256100
Dear Dr. Dispersyn:
            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 Jeffrey Gabor at 202-551-2544 with any questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:       Ryan A. Murr, Esq.

CORRESP
1
filename1.htm

Phio Pharmaceuticals
Corp.

257 Simarano Drive, Suite 101 | Marlborough,
MA 01752

February 5, 2021

VIA EDGAR

Securities and Exchange Commission

Division of Corporation Finance

100 F Street, N.E.

Washington, DC 20549

Attn: Ada Sarmento

    Re:
    Phio Pharmaceuticals Corp.

        Registration Statement on Form S-3

        (File No. 333-252588)

Ladies and Gentlemen:

Pursuant to Rule 461 under the Securities
Act of 1933, as amended, Phio Pharmaceuticals Corp. (the “Company”) hereby respectfully requests that
the effective date of the above-referenced registration statement on Form S-3 filed by the Company on January 29, 2021, as amended
by Amendment No. 1 filed by the Company on February 4, 2021 (the “Registration Statement”), be accelerated
so that the Registration Statement will be declared effective at 5:00 p.m., Eastern Time, on February 8, 2021, or as soon thereafter
as practicable.

    Very truly yours,

    PHIO PHARMACEUTICALS CORP.

    /s/ Gerrit Dispersyn

    Gerrit Dispersyn, Dr. Med. Sc.

    President and Chief Executive Officer

cc: Ryan A. Murr, Gibson, Dunn & Crutcher LLP

United States securities and exchange commission logo
February 2, 2021
Gerrit Dispersyn, Dr. Med. Sc.
Chief Executive Officer
Phio Pharmaceuticals Corp.
257 Simarano Drive, Suite 101
Marlborough, MA 01752
Re:Phio Pharmaceuticals Corp.
Registration Statement on Form S-3
Filed January 29, 2021
File No. 333-252588
Dear Dr. Dispersyn:
            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,
Division of Corporation Finance
Office of Life Sciences
cc:       Ryan A. Murr, Esq.

CORRESP
1
filename1.htm

Phio
Pharmaceuticals Corp.

257 Simarano Drive, Suite 101 | Marlborough,
MA 01752

July 15, 2020

VIA EDGAR

Securities and Exchange Commission

Division of Corporation Finance

100 F Street, N.E.

Washington, DC 20549

 Attn: Paul Fischer

    Re:
    Phio Pharmaceuticals Corp.

    Registration Statement on Form S-1 (File No. 333-239779)

Ladies and Gentlemen:

Pursuant to Rule 461 under the Securities
Act of 1933, as amended, Phio Pharmaceuticals Corp. (the “Company”) hereby respectfully requests that
the effective date of the above-referenced registration statement on Form S-1 filed by the Company (the “Registration
Statement”) be accelerated so that it will be declared effective at 4:30 p.m., Eastern Time, on July 17, 2020, or
as soon thereafter as practicable.

    Very truly yours,

    PHIO PHARMACEUTICALS CORP.

    /s/ Gerrit Dispersyn

    Gerrit Dispersyn, Dr. Med. Sc.

    President and Chief Executive Officer

cc: Ryan A. Murr, Gibson, Dunn & Crutcher LLP

United States securities and exchange commission logo
July 15, 2020
Gerrit Dispersyn
President & CEO
Phio Pharmaceuticals Corp.
257 Simarano Drive, Suite 101
Marlborough, Massachusetts 01752
Re:Phio Pharmaceuticals Corp.
Registration Statement on Form S-1
Filed July 9, 2020
File No. 333-239779
Dear Mr. Dispersyn:
            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 Margaret Schwartz at 202-551-7153 with any questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences

CORRESP
1
filename1.htm

Phio Pharmaceuticals
Corp.

257 Simarano Drive, Suite 101 | Marlborough,
MA 01752

May 29, 2020

VIA EDGAR

Securities and Exchange Commission

Division of Corporation Finance

100 F Street, N.E.

Washington, DC 20549

 Attn: Paul Fischer

 Re: Phio Pharmaceuticals Corp.

    Registration Statement on Form S-1 (File
                                         No. 333-238204)

Ladies and Gentlemen:

Pursuant to Rule 461 under the Securities
Act of 1933, as amended, Phio Pharmaceuticals Corp. (the “Company”) hereby respectfully requests that
the effective date of the above-referenced registration statement on Form S-1 filed by the Company (the “Registration
Statement”) be accelerated so that it will be declared effective at 4:30 p.m., Eastern Time, on June 1, 2020, or
as soon thereafter as practicable.

    Very truly yours,

    PHIO PHARMACEUTICALS CORP.

    /s/ Gerrit Dispersyn

    Gerrit Dispersyn, Dr. Med. Sc.

    President and Chief Executive Officer

cc: Ryan A. Murr, Gibson, Dunn & Crutcher LLP

CORRESP
1
filename1.htm

May 28, 2020

VIA EDGAR AND ELECTRONIC MAIL

U.S. Securities and Exchange Commission

Division of Corporation Finance

Office of Life Sciences

100 F Street, N.E.

Washington, D.C. 20549-4561

    Re:
    Phio Pharmaceuticals Corp.

    Registration Statement on Form S-1

    Filed May 12, 2020

    File No. 333-238204

Ladies and Gentlemen:

On behalf of Phio
Pharmaceuticals Corp. (“Phio” or the “Company”) and in response to the comment of the staff
(the “Staff”) of the U.S. Securities and Exchange Commission (the “Commission”) to the Company’s
Registration Statement on Form S-1 filed with the Commission on May 12, 2020 (the “Registration Statement”)
contained in your letter dated May 21, 2020 (the “Comment Letter”), we submit this letter containing the Company’s
response to the Comment Letter. In connection with this letter, the Company is filing an amendment to the Registration Statement
(“Amendment No. 1”) on the date hereof. We are separately sending to the Staff a copy of this letter and a version
of Amendment No. 1 marked to show the changes made to the Registration Statement.

For your convenience,
we have set out the text in bold of the comment from the Comment Letter followed by our response in regular typeface. The page
number referenced in the response refers to the page number in Amendment No. 1.

Registration Statement on Form
S-1

General

 1. We note that the exclusive jurisdiction provision in your amended and restated certificate of incorporation identifies the
Court of Chancery of the State of Delaware as the exclusive forum for certain litigation, including any “derivative action.”
Please revise to describe this provision and disclose whether this provision applies to actions arising under the Securities Act
or Exchange Act. If this provision does not apply to actions arising under the Securities Act or Exchange Act, please also tell
us how you will inform investors in future filings that the provision does not apply to any actions arising under the Securities
Act or Exchange Act. With respect to your future filings, we refer to counsel's September 25, 2019 correspondence relating to your
Form S-1 filed on August 30, 2019 (File No. 333-233584). We note the representation that you would include disclosure in your next
annual report on Form 10-K to reflect that the forum selection provisions do not apply to actions arising under the Exchange Act,
Securities Act, or for any other claim for which the federal courts have exclusive jurisdiction; however, we do not see this disclosure
in your Form 10-K for the fiscal year ended December 31, 2019.

May 28, 2020

Page 2

Response:

In response to the Staff’s comment,
the disclosure in the Registration Statement on page 4 has been revised to confirm that the forum selection provisions in the Company’s
amended and restated certificate of incorporation will not apply to actions arising under the Exchange Act, Securities Act, or
for any other claim for which the federal courts have exclusive jurisdiction. The Company will add similar disclosure to its next
Quarterly Report on Form 10-Q and in its Annual Report on Form 10-K for the year ending December 31, 2020.

*      *      *

If you have any questions concerning the
foregoing, please do not hesitate to contact the undersigned at (415) 393-8373.

    Very truly yours,

/s/ Ryan A. Murr

Ryan A. Murr

Enclosures

cc:   Gerrit Dispersyn, Chief Executive Officer, Phio Pharmaceuticals
Corp.

United States securities and exchange commission logo
May 21, 2020
Geritt Dispersyn, Dr.Med.Sc.
Chief Executive Offficer
Phio Pharmaceuticals Corp.
257 Simerano Drive, Suite 101
Marlborough, MA 01752
Re:Phio Pharmaceuticals Corp.
Registration Statement on Form S-1
Filed May 12, 2020
File No. 333-238204
Dear Dr. Dispersyn:
            We have limited our review of your registration statement to those issues we have
addressed in our comment.  Please respond to this letter by amending your registration statement
and providing the requested information.  If 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 reviewing any amendment to your registration statement and the information you
provide in response to this comment, we may have additional comments.
Registration Statement on Form S-1, filed on May 12, 2020
General
1.We note that the exclusive jurisdiction provision in your amended and restated certificate
of incorporation identifies the Court of Chancery of the State of Delaware as the exclusive
forum for certain litigation, including any “derivative action.” Please revise to describe
this provision and disclose whether this provision applies to actions arising under the
Securities Act or Exchange Act. If this provision does not apply to actions arising under
the Securities Act or Exchange Act, please also tell us how you will inform investors in
future filings that the provision does not apply to any actions arising under the Securities
Act or Exchange Act.  With respect to your future filings, we refer to counsel's September
25, 2019 correspondence relating to your Form S-1 filed on August 30, 2019 (File
No. 333-233584).  We note the representation that you would include disclosure in your
next annual report on Form 10-K to reflect that the forum selection provisions do not
apply to actions arising under the Exchange Act, Securities Act, or for any other claim for
which the federal courts have exclusive jurisdiction; however, we do not see this

 FirstName LastNameGeritt  Dispersyn, Dr.Med.Sc.
 Comapany NamePhio Pharmaceuticals Corp.
 May 21, 2020 Page 2
 FirstName LastName
Geritt  Dispersyn, Dr.Med.Sc.
Phio Pharmaceuticals Corp.
May 21, 2020
Page 2
disclosure in your Form 10-K for the fiscal year ended December 31, 2019.

            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 Paul Fischer, Staff Attorney, at 202-551-3415, or Joe McCann, Legal
Branch Chief, at 202-551-6262, with any questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:       Ryan Murr, Esq.

CORRESP
1
filename1.htm

Phio Pharmaceuticals Corp.

257 Simarano Drive, Suite 101

Marlborough, MA 01752

(508) 767-3861

February 7, 2020

VIA EDGAR

Securities and Exchange Commission

Division of Corporation Finance

100 F Street, N.E.

Washington, DC 20549

Attn: Joseph McCann

 Re: Phio Pharmaceuticals Corp.

    Registration Statement on
Form S-1

    Filed October 1, 2019

    File No. 333-234032

Ladies and Gentlemen:

Pursuant to Rules 460
and 461 promulgated under the Securities Act of 1933, as amended, Phio Pharmaceuticals Corp., a Delaware corporation (the
“Company”), hereby respectfully requests that the effective time of the above referenced Registration Statement on
Form S-1 filed by the Company (the “Registration Statement”) be accelerated to 9:00 a.m., Eastern Daylight Time, on,
February 11, 2020 or as soon thereafter as practicable.

    Very truly yours,

    Phio Pharmaceuticals Corp.

    /s/ Gerrit Dispersyn

    Gerrit Dispersyn

    President and Chief Executive Officer

cc:	Ryan A. Murr, Gibson, Dunn & Crutcher LLP

CORRESP
1
filename1.htm

February 7, 2020

VIA EDGAR

U.S. Securities and Exchange Commission

Division of Corporation Finance

100 F Street, N.E.

Washington, D.C. 20549

 Re: Phio
Pharmaceuticals Corp.

    Registration
Statement on Form S-1 (Registration No. 333-234032)

    Concurrence
in Acceleration Request

Ladies and Gentlemen:

H.C. Wainwright &
Co., LLC (“Wainwright”), as underwriter for the referenced offering, hereby concurs in the request by Phio Pharmaceuticals
Corp. that the effective date of the above-referenced registration statement be accelerated to 9:00 a.m. (Eastern Time),
or as soon as practicable thereafter, on February 11, 2020 pursuant to Rule 461 under the Securities Act. Wainwright affirms that
it is aware of its obligations under the Securities Act in connection with this offering.

    Very truly yours,

    H.C. WAINWRIGHT & CO., LLC

    By:
    /s/
Edward D. Silvera

    Name:
    Edward D. Silvera
 Title: Chief Operating Officer

October 8, 2019
Gerrit Dispersyn
President & Chief Executive Officer
Phio Pharmaceuticals Corp.
257 Simarano Drive, Suite 101
Marlborough, MA 01752
Re:Phio Pharmaceuticals Corp.
Registration Statement on Form S-1
Filed October 1, 2019
File No. 333-234032
Dear Dr. Dispersyn:
            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 Joseph McCann at (202) 551-6262 with any questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences

CORRESP
1
filename1.htm

Phio Pharmaceuticals
Corp.

257 Simarano Drive, Suite 101 | Marlborough,
MA 01752

September 27, 2019

VIA EDGAR

Securities and Exchange Commission

Division of Corporation Finance

100 F Street, N.E.

Washington, DC 20549

 Attn:      Donald Field

 Re: Phio Pharmaceuticals Corp.

    Registration Statement on Form S-1 (File
                                         No. 333-233584)

Ladies and Gentlemen:

Pursuant to Rule 461 under the Securities
Act of 1933, as amended, Phio Pharmaceuticals Corp. (the “Company”) hereby respectfully requests that
the effective date of the above-referenced registration statement on Form S-1 filed by the Company (the “Registration
Statement”) be accelerated so that it will be declared effective at 5:00 p.m., Eastern Time, on October 1, 2019,
or as soon thereafter as practicable.

    Very truly yours,

    PHIO PHARMACEUTICALS CORP.

    /s/ Gerrit Dispersyn

    Gerrit Dispersyn, Dr. Med. Sc.

    President and Chief Executive Officer

cc: Ryan A. Murr, Gibson, Dunn & Crutcher LLP

CORRESP
1
filename1.htm

Gibson, Dunn & Crutcher LLP

555 Mission
Street

San Francisco,
CA 94105-0921

Tel 415-393-8200

www.gibsondunn.com

Ryan A. Murr

Direct: +1
415.393.8373

Fax: +1 415.374.8430

RMurr@gibsondunn.com

September 25, 2019

VIA EDGAR AND ELECTRONIC MAIL

U.S. Securities and Exchange Commission

Division of Corporation Finance

Office of Healthcare & Insurance

100 F Street, N.E.

Washington, D.C. 20549-4561

    Re:
    Phio Pharmaceuticals Corp.

    Registration Statement on Form S-1

    Filed August 30, 2019

    File No. 333-233584

Dear Division of Corporation Finance:

On behalf of Phio
Pharmaceuticals Corp. (“Phio” or the “Company”) and in response to the comment of the staff
(the “Staff”) of the U.S. Securities and Exchange Commission (the “Commission”) to the Company’s
Registration Statement on Form S-1 filed with the Commission on August 30, 2019 (the “Registration Statement”)
contained in your letter dated September 10, 2019 (the “Comment Letter”), we submit this letter containing the
Company’s response to the Comment Letter. In connection with this letter, the Company is filing an amendment to the Registration
Statement (“Amendment No. 1”) on the date hereof. We are separately sending to the Staff a copy of this letter
and a version of Amendment No. 1 marked to show the changes made to the Registration Statement.

For your convenience,
we have set out the text in bold of the comment from the Comment Letter followed by our response in regular typeface. The page
number referenced in the response refers to the page number in Amendment No. 1.

Registration Statement on Form
S-1

General

1. We note that your exclusive jurisdiction provision in your amended and restated certificate of incorporation identifies
the Court of Chancery of the State of Delaware as the exclusive forum for certain litigation, including any “derivative action.”
Please revise to describe this provision and disclose whether this provision applies to actions arising under the Securities Act
or Exchange Act. In that regard, we note that Section 27 of the Exchange Act creates exclusive federal jurisdiction over all suits
brought to enforce any duty or liability created by the Exchange Act or the rules and regulations thereunder, and Section 22 of
the Securities Act creates concurrent jurisdiction for federal and state courts over all suits brought to enforce any duty or liability
created by the Securities Act or the rules and regulations thereunder. If the provision applies to Securities Act claims, please
also revise your prospectus to state that there is uncertainty as to whether a court would enforce such provision and that investors
cannot waive compliance with the federal securities laws and the rules and regulations thereunder. If this provision does not apply
to actions arising under the Securities Act or Exchange Act, please also tell us how you will inform investors in future filings
that the provision does not apply to any actions arising under the Securities Act or Exchange Act.

September 25, 2019

Page 2

 Response:

In response to the Staff’s comment,
and as discussed telephonically with the Staff, the disclosure in the Registration Statement on page 2 has been revised to confirm
that the forum selection provisions in the Company’s amended and restated certificate of incorporation will not apply to
actions arising under the Exchange Act, Securities Act, or for any other claim for which the federal courts have exclusive jurisdiction.
The Company will add similar disclosure to its next Annual Report on Form 10-K.

*       *       *

If you have any questions concerning the
foregoing, please do not hesitate to contact the undersigned at (415) 393-8373.

    Very truly yours,

    /s/ Ryan A. Murr

    Ryan A. Murr

Enclosures

cc:       Gerrit Dispersyn, Chief Executive Officer, Phio Pharmaceuticals
Corp.

September 10, 2019
Gerrit Dispersyn
Chief Executive Officer
Phio Pharmaceuticals Corp.
257 Simarano Drive, Suite 101
Marlborough, MA 01752
Re:Phio Pharmaceuticals Corp.
Registration Statement on Form S-1
Filed August 30, 2019
File No. 333-233584
Dear Dr. Dispersyn:
            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 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.
Registration Statement on Form S-1
General
1.We note that your exclusive jurisdiction provision in your amended and restated
certificate of incorporation identifies the Court of Chancery of the State of Delaware as
the exclusive forum for certain litigation, including any “derivative action.”  Please revise
to describe this provision and disclose whether this provision applies to actions arising
under the Securities Act or Exchange Act.  In that regard, we note that Section 27 of the
Exchange Act creates exclusive federal jurisdiction over all suits brought to enforce any
duty or liability created by the Exchange Act or the rules and regulations thereunder, and
Section 22 of the Securities Act creates concurrent jurisdiction for federal and state courts
over all suits brought to enforce any duty or liability created by the Securities Act or the
rules and regulations thereunder.  If the provision applies to Securities Act claims, please

 FirstName LastNameGerrit Dispersyn
 Comapany NamePhio Pharmaceuticals Corp.
 September 10, 2019 Page 2
 FirstName LastName
Gerrit Dispersyn
Phio Pharmaceuticals Corp.
September 10, 2019
Page 2
also revise your prospectus to state that there is uncertainty as to whether a court would
enforce such provision and that investors cannot waive compliance with the federal
securities laws and the rules and regulations thereunder.  If this provision does not apply
to actions arising under the Securities Act or Exchange Act, please also tell us how you
will inform investors in future filings that the provision does not apply to any actions
arising under the Securities Act or Exchange Act.
            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 Donald Field at 202-551-3680 or Justin Dobbie at 202-551-3469 with
any questions.
Sincerely,
Division of Corporation Finance
Office of Healthcare & Insurance

CORRESP
1
filename1.htm

September 28, 2018

VIA EDGAR

U.S. Securities and Exchange Commission

Division of Corporation Finance

100 F Street, N.E.

Washington, D.C. 20549

    Re:
    RXi Pharmaceuticals Corporation

    Registration Statement on Form S-1 (Registration No. 333-227173)

    Concurrence in Acceleration Request

Ladies and Gentlemen:

H.C. Wainwright &
Co., LLC (“Wainwright”), as underwriter for the referenced offering, hereby concurs in the request by RXi Pharmaceuticals
Corporation that the effective date of the above-referenced registration statement be accelerated to 5:00 p.m. (Eastern Time),
or as soon as practicable thereafter, on September 28, 2018, pursuant to Rule 461 under the Securities Act. Wainwright affirms
that it is aware of its obligations under the Securities Act in connection with this offering.

    Very truly yours,

    H.C. WAINWRIGHT & CO., LLC

    By:
    /s/ Mark W. Viklund

    Name: Mark W. Viklund

Title: Chief Executive Officer

CORRESP
1
filename1.htm

RXi Pharmaceuticals Corporation

257 Simarano Drive, Suite 101

Marlborough, MA 01752

(508) 767-3861

September 28, 2018

VIA EDGAR

Securities and Exchange Commission

Division of Corporation Finance

100 F Street, N.E.

Washington, DC 20549

Attn: Dorrie Yale

 Re: RXi Pharmaceuticals Corporation

Registration Statement on
Form S-1

Filed August 31, 2018

File No. 333-227173

Ladies and Gentlemen:

Pursuant to Rules 460
and 461 promulgated under the Securities Act of 1933, as amended, RXi Pharmaceuticals Corporation, a Delaware corporation
(the “Company”), hereby respectfully requests that the effective time of the above referenced Registration Statement
on Form S-1 filed by the Company (the “Registration Statement”) be accelerated to 5:00 p.m., Eastern Daylight Time,
on, September 28, 2018 or as soon thereafter as practicable.

Very truly yours,

RXi Pharmaceuticals Corporation

/s/ Geert Cauwenbergh

Geert Cauwenbergh

President, Chief Executive Officer and acting Chief Financial Officer

cc:                      Ryan A. Murr, Gibson, Dunn & Crutcher LLP

September 10, 2018
Geert Cauwenbergh
President and Chief Executive Officer
RXi Pharmaceuticals Corporation
257 Simarano Drive, Suite 101
Marlborough, MA 01752
Re:RXi Pharmaceuticals Corporation
Registration Statement on Form S-1
Filed August 31, 2018
File No. 333-227173
Dear Dr. Cauwenbergh:
            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 Dorrie Yale at 202-551-8776 with any questions.
Sincerely,
Division of Corporation Finance
Office of Healthcare & Insurance
cc:       Ryan Murr

CORRESP
1
filename1.htm

CORRESP

 RXi Pharmaceuticals Corporation

257 Simarano Drive, Suite 101

Marlborough, MA 01752

 (508) 767-3861

 May 31, 2018

VIA EDGAR

 Securities and Exchange Commission

Division of Corporation Finance

 100 F Street, N.E.

Washington, DC 20549

 Attn: Irene Paik

Re:
RXi Pharmaceuticals Corporation

 Registration Statement on
Form S-1

 Filed May 9, 2018

File No. 333-224799

Ladies and Gentlemen:

 Pursuant to Rules 460
and 461 promulgated under the Securities Act of 1933, as amended, RXi Pharmaceuticals Corporation, a Delaware corporation (the “Company”), hereby respectfully requests that the effective time of the above referenced Registration
Statement on Form S-1 filed by the Company (the “Registration Statement”) be accelerated to 4:00 p.m., Eastern Daylight Time, on, May 31, 2018 or as soon thereafter as practicable.

[Signature page follows]

Very truly yours,

RXi Pharmaceuticals Corporation

 /s/ Geert Cauwenbergh

Geert Cauwenbergh

President, Chief Executive Officer and acting Chief Financial Officer

cc:
Ryan A. Murr, Gibson, Dunn & Crutcher LLP

CORRESP
1
filename1.htm

CORRESP

 RXi Pharmaceuticals Corporation

257 Simarano Drive, Suite 101

Marlborough, MA 01752

 (508) 767-3861

 May 23, 2018

VIA EDGAR

 Securities and Exchange Commission

Division of Corporation Finance

 100 F Street, N.E.

Washington, DC 20549

 Attn: Irene Paik

Re:
RXi Pharmaceuticals Corporation

 Registration Statement on Form S-1

 Filed May 9, 2018

File No. 333-224799

Ladies and Gentlemen:

 Pursuant to Rules 460
and 461 promulgated under the Securities Act of 1933, as amended, RXi Pharmaceuticals Corporation, a Delaware corporation (the “Company”), hereby respectfully requests that the effective time of the above referenced Registration
Statement on Form S-1 filed by the Company (the “Registration Statement”) be accelerated to 4:00 p.m., Eastern Daylight Time, on, May 25, 2018 or as soon thereafter as practicable.

[Signature page follows]

Very truly yours,

RXi Pharmaceuticals Corporation

/s/ Geert Cauwenbergh

Geert Cauwenbergh

President, Chief Executive Officer and acting Chief

Financial Officer

cc:
Ryan A. Murr, Gibson, Dunn & Crutcher LLP

May 16, 2018
Geert Cauwenbergh
President
RXi Pharmaceuticals Corporation
257 Simarano Drive, Suite 101
Marlborough, Massachusetts 01752
Re:RXi Pharmaceuticals Corporation
Registration Statement on Form S-1
Filed May 9, 2018
File No. 333-224799
Dear Dr. Cauwenbergh:
            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.
Division of Corporation Finance
Office of Healthcare & Insurance
cc:       Ryan A. Murr - Gibson, Dunn & Crutcher LLP

April 5, 2018
Geert Cauwenbergh
President, Chief Executive Officer and acting Chief Financial Officer
RXi Pharmaceuticals Corporation
257 Simarano Drive, Suite 101
Marlborough, MA 01752
Re:RXi Pharmaceuticals Corporation
Registration Statement on Form S-3
Filed March 29, 2018
File No. 333-224031
Dear Dr. Cauwenbergh:
            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 Jeffrey Gabor at 202-551-2544 with any questions.
Division of Corporation Finance
Office of Healthcare & Insurance
cc: Ryan A. Murr, Esq.

CORRESP
1
filename1.htm

CORRESP

 RXi Pharmaceuticals Corporation

257 Simarano Drive, Suite 101

Marlborough, MA 01752

 (508) 767-3861

 April 5, 2018

VIA EDGAR

 Securities and Exchange Commission

Division of Corporation Finance

 100 F Street, N.E.

Washington, DC 20549

 Attn: Jeffrey Gabor

Re:
RXi Pharmaceuticals Corporation

Registration Statement on Form S-3

Filed March 29, 2018 File No. 333-224031

Ladies and Gentlemen:

 Pursuant to
Rule 461 promulgated under the Securities Act of 1933, as amended, RXi Pharmaceuticals Corporation, a Delaware corporation (the “Company”), hereby respectfully requests that the effective time of the above referenced Registration
Statement on Form S-3 filed by the Company (the “Registration Statement”) be accelerated to 4:00 p.m., Eastern Daylight Time, on April 6, 2018 or as soon thereafter as practicable.

[Signature page follows]

 Very truly yours,

RXi Pharmaceuticals Corporation

/s/ Geert Cauwenbergh

 Geert Cauwenbergh

 President, Chief Executive
Officer and acting Chief

 Financial Officer

cc:
Ryan A. Murr, Gibson, Dunn & Crutcher LLP

CORRESP
1
filename1.htm

Acceleration Request

 RXi Pharmaceuticals Corporation

257 Simarano Drive, Suite 101 | Marlborough, MA 01752

August 28, 2017

 VIA EDGAR

Securities and Exchange Commission

 Division of Corporation
Finance

 100 F Street, N.E.

 Washington, DC 20549

Attn:
Christopher Edwards

Re:
RXi Pharmaceuticals Corporation

Registration Statement on Form S-1 (File No. 333-220062)

Ladies and Gentlemen:

 Pursuant to Rule 461
under the Securities Act of 1933, as amended, RXi Pharmaceuticals Corporation (the “Company”) hereby requests that the effective date of the above-captioned registration statement (the “Registration Statement”) be
accelerated so that it becomes effective at 4:00 p.m., Eastern Time, on August 30, 2017, or as soon thereafter as practicable.

 Please
call Ryan Murr of Gibson, Dunn & Crutcher LLP at (415) 393-8373 as soon as the Registration Statement has been declared effective.

Very truly yours,

RXi PHARMACEUTICALS CORPORATION

By:

/s/ Geert Cauwenbergh

Name:

Geert Cauwenbergh, Dr. Med. Sc.

Title:

President, Chief Executive Officer and Chief Financial Officer

August 25, 2017
Dr. Geert Cauwenbergh
President
RXi Pharmaceuticals Corporation
257 Simarano Drive, Suite 101
Marlborough, Massachusetts 01752
RXi Pharmaceuticals Corporation
Registration Statement on Form S-1
Filed August 18, 2017
File No. 333-220062Re:
Dear Dr. Cauwenbergh:
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 Chris Edwards at (202) 551-6761 with any questions.
Division of Corporation Finance
Office of Healthcare & Insurance
cc: Ryan A. Murr

CORRESP
1
filename1.htm

CORRESP

 RXi Pharmaceuticals Corporation

257 Simarano Drive, Suite 101 | Marlborough, MA 01752

August 4, 2017

 VIA EDGAR

Securities and Exchange Commission

 Division of Corporation
Finance

 100 F Street, N.E.

 Washington, DC 20549

Attn: Christine Westbrook

Re:
RXi Pharmaceuticals Corporation

Registration Statement on Form S-1 (File No. 333-219300)

 Ladies and Gentlemen:

Pursuant to Rule 461 under the Securities Act of 1933, as amended, RXi Pharmaceuticals Corporation (the “Company”)
hereby requests that the effective date of the above-captioned registration statement (the “Registration Statement”) be accelerated so that it becomes effective at 4:00 p.m., Eastern Time, on August 8, 2017, or as soon
thereafter as practicable.

 Please call Ryan Murr of Gibson, Dunn & Crutcher LLP at (415) 393-8373 as soon as the
Registration Statement has been declared effective.

 Very truly yours,

RXi PHARMACEUTICALS CORPORATION

By:

/s/ Geert Cauwenbergh

 Name: Geert Cauwenbergh, Dr. Med. Sc.

Title: President, Chief Executive Officer and Chief Financial Officer

CORRESP
1
filename1.htm

Acceleration request

 Ladenburg Thalmann & Co. Inc.

December 15, 2016

VIA FACSIMILE AND EDGAR

 U.S. Securities and
Exchange Commission

 Division of Corporate Finance

Washington, DC 20549

Re:
RXI PHARMACEUTICALS CORPORATION

Registration Statement on Form S-1 (Registration No. 333-214199) -

Concurrence in Acceleration Request

 Ladies and Gentlemen:

Ladenburg Thalmann & Co., Inc. (“Ladenburg”), as representative of the underwriters for the referenced offering,
hereby concurs in the request by RXi Pharmaceuticals Corporation that the effective date of the above-referenced registration statement be accelerated to 4:05 p.m. (Eastern Time), or as soon as practicable thereafter, on December 15, 2016,
pursuant to Rule 461 under the Securities Act. Ladenburg affirms that it is aware of its obligations under the Securities Act in connection with this offering.

 Very truly yours,

LADENBURG THALMANN & CO. INC.

By:

/s/ Nicholas Stergis

 Name: Nicholas Stergis

 Title: Managing
Director

CORRESP
1
filename1.htm

CORRESP

 RXi Pharmaceuticals Corporation

257 Simarano Drive, Suite 101 | Marlborough, MA 01752

December 14, 2016

 VIA EDGAR

Securities and Exchange Commission

 Division of Corporation
Finance

 100 F Street, N.E.

 Washington, DC 20549

Attn:    Joseph McCann

 Mary
Beth Breslin

Re:
RXi Pharmaceuticals Corporation

Registration Statement on Form S-1 (File No. 333-214199)

 Ladies and Gentlemen:

Pursuant to Rule 461 under the Securities Act of 1933, as amended, RXi Pharmaceuticals Corporation (the “Company”)
hereby requests that the effective date of the above-captioned registration statement (the “Registration Statement”) be accelerated so that it becomes effective at 4:05 p.m., Eastern Time, on December 15, 2016, or as
soon thereafter as 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 filing;

•

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 the effectiveness of the Registration Statement as a defense in any proceeding initiated by the Commission or any person under the federal securities laws
of the United States.

 Please call Ryan Murr of Gibson, Dunn & Crutcher LLP at (415) 393-8373 as soon as the
Registration Statement has been declared effective.

Very truly yours,

RXi PHARMACEUTICALS CORPORATION

By:

/s/ Geert Cauwenbergh

Name:

Geert Cauwenbergh, Dr. Med. Sc.

Title:

President, Chief Executive Officer and Chief Financial Officer

CORRESP
1
filename1.htm

Response Letter

 December 7, 2016

VIA EDGAR

 Division of Corporation Finance

Office of Healthcare and Insurance

 U.S. Securities and Exchange
Commission

 100 F Street, N.E.

 Washington, D.C. 20549

Re:
RXi Pharmaceuticals Corp.

Registration Statement on Form S-1

Filed October 21, 2016

File No. 333-214199

 Dear Ladies and Gentlemen:

On behalf of RXi Pharmaceuticals Corp. (“RXi” or the “Company”), and in response to the comments of the staff
(the “Staff”) of the U.S. Securities and Exchange Commission (the “Commission”) to Amendment No. 2 to the Company’s Registration Statement on Form S-1 filed with the Commission on November 30, 2016
(the “Registration Statement”) contained in your letter dated December 5, 2016 (the “Comment Letter”), we submit this letter containing the Company’s responses to the Comment Letter.

The responses set forth in this letter are numbered to correspond to the comments in the Comment Letter. For your convenience, we have set out
the text in bold of the sole comment from the Comment Letter followed by our response.

 Exhibits

1.
We refer to Exhibit 5.1. Please have counsel revise to opine on the legality of the Class A and Class B units.

Response: We have considered the Staff’s request to include an opinion as to the legality of the Class A and Class B Units referred to
in the prospectus (jointly, the “Units”), including considering the guidance contained in Staff Legal Bulletin No. 19 (“SLB 19”). Following this review, we respectfully submit that no opinion should be required, as the Units
are not securities.

 Page 2

As disclosed in the prospectus, the Class A Units consist solely of common stock and warrants, while the Class B Units consist solely of preferred stock,
warrants, and common stock underlying the preferred stock. There is no separate instrument defining the rights of the Units as they have no stand-alone rights. The Units are not certificated and will not be issued as a stand-alone security. As noted
on the cover page of the prospectus, “The Class A Units and Class B Units will not be certificated and the shares of common stock, Series B Convertible Preferred Stock and warrants comprising such units are immediately separable and will
be issued separately in this offering.”

 The use of the term “unit” in the prospectus is solely intended to convey that the common
stock-and-warrant combination (with respect to the Class A Units) and the preferred stock-and-warrant combination (with respect to the Class B Units) will be offered together and sold in fixed ratios. Purchasers in the offering only have the
right to purchase a combination of a share of common or preferred stock and a warrant, and not other combinations of the offered securities, such as common stock with no warrants, or just warrants with no common stock. Thus, the term
“unit” is simply being used as a convenience to refer to the bundling of the component securities that will be offered and sold in fixed ratios.

In looking at the guidance in SLB 19 regarding legal opinions for unit offerings, the Staff notes that, “[t]he Division has traditionally asked for a
binding obligation opinion with respect to the legality of the units.” In this case, there is no instrument or agreement defining rights of the Units themselves, as the Units are just the component parts and nothing more. Thus, we respectfully
submit that it would not be possible to render a legal opinion on the legality or enforceability of a right or instrument that does not exist. SLB 19 goes on to note that in some instances, the Division may accept an opinion to the effect that the
units are legally issued, fully paid and non-assessable (as determined under applicable state law). However, given that the units are not equity securities under Delaware law, there is no statutory framework to apply to their issuance and thus no
framework against which to render a legal opinion.

 In speaking with the Staff regarding this comment, we understand that the inclusion of the
Class A Units and Class B Unit on the fee table for the Registration Statement may have unintentionally conveyed the issuer’s view that the Units were in fact separate securities being offered under the prospectus. To the extent that the
Staff concurs that no opinion should be required in this context, we would intend to file a pre-effective amendment with a revised fee table that omits any reference to the Units and instead refers solely to the offered securities underlying the
Units.

 *    *    *    *    *    *

 Page 3

If you have any questions concerning the foregoing, please do not hesitate to contact the undersigned at (415) 393-8373.

Very truly yours,

/s/ Ryan A. Murr

Ryan A. Murr

 Enclosures

cc:
Geert Cauwenbergh, Dr. Med. Sc., RXi Pharmaceuticals Corporation

December 5, 2016
Geert Cauwenbergh
President and Chief Executive Officer
RXi Pharmaceuticals Corp.
257 Simarano Drive, Suite 101
Suite Marlborough, MA 01752
RXi Pharmaceuticals Corp.
Amendment No. 2 to Registration Statement on Form S-1
Filed November 30, 2016
File No. 333-214199Re:
Dear Dr. Cauwenbergh:
         We have reviewed your amended registration statement and have the following
comment.  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 comment applies 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 the comment, we may have additional comments.
Amendment No. 2 to Registration Statement on Form S-1
Exhibits
We refer to Exhibit 5.1.  Please have counsel revise to opine on the legality of the Class A
and Class B units.1.
         Please contact Joseph McCann at (202) 551-6262 or Mary Beth Breslin at (202) 551-
3625 with any questions.
Division of Corporation Finance
Office of Healthcare & Insurance

CORRESP
1
filename1.htm

CORRESP

 Gibson, Dunn & Crutcher LLP

 555 Mission Street

San Francisco, CA 94105-0921

Tel 415.393.8200

www.gibsondunn.com

 Ryan A. Murr

 Direct: +1 415.393.8373

Fax: +1 415.374.8430

 RMurr@gibsondunn.com

 November 10, 2016

VIA EDGAR AND OVERNIGHT MAIL

 Division of Corporation
Finance

 Office of Healthcare and Insurance

 U.S. Securities
and Exchange Commission

 100 F Street, N.E.

 Washington, D.C.
20549

Re:
RXi Pharmaceuticals Corp.

Registration Statement on Form S-1

Filed October 21, 2016

File No. 333-214199

 Dear Division of Corporation Finance:

On behalf of RXi Pharmaceuticals Corp. (“RXi” or the “Company”), and in response to the comments of the
staff (the “Staff”) of the U.S. Securities and Exchange Commission (the “Commission”) to the Company’s Registration Statement on Form S-1 filed with the Commission on October 21, 2016 (the “Registration
Statement”) contained in your letter dated November 4, 2016 (the “Comment Letter”), we submit this letter containing the Company’s responses to the Comment Letter. In connection with this letter, the Company is
filing an amendment to the Registration Statement (“Amendment No. 1”) on the date hereof. We are separately sending to the Staff a copy of this letter and a version of Amendment No. 1 marked to show the
changes made to the Registration Statement.

 The responses set forth in this letter are numbered to correspond to the numbered comments in
the Comment Letter. For your convenience, we have set out the text in bold of the comments from the Comment Letter followed by our responses. Page numbers referenced in the responses refer to page numbers in Amendment No. 1.

Facing Page

1.
In your Fee Table, please revise to calculate the registration fee of the units based on the offer price of the units and the exercise price of the warrants, and calculate the fee of the common stock underlying the
warrants based on the exercise price of the warrants. For guidance, please refer to Securities Act Rules Compliance and Disclosure Interpretations 240.05 and 240.06, available on the Commission’s website.

Response: In response to the Staff’s comment, the Fee Table in the Registration Statement has been revised on the
facing page of Amendment No. 1.

 Beijing • Brussels • Century
City • Dallas • Denver • Dubai • Frankfurt • Hong Kong • London • Los Angeles • Munich

New York • Orange County • Palo Alto • Paris • San
Francisco • São Paulo • Singapore • Washington, D.C.

  Page
 2

 Cover Page

2.
Although Rule 430A of the Securities Act of 1933 permits registrants to omit certain pricing-related information from a registration statement that is declared effective, your filing must include the amount of
securities to be offered in a pre-effective amendment. Accordingly, please confirm that you will revise your disclosure to specify: (i) the number of each of the Class A units and Class B units to be offered; (ii) the number of shares of common
stock per Class A unit and the number of shares of Series B Convertible Preferred shares per Class B unit; and (iii) the number of warrants per each Class A unit and Class B unit.

Response: In response to the Staff’s comment, the disclosure in the Registration Statement has been revised throughout
the Registration Statement to reflect (i) the number of each of the Class A units and Class B units to be offered; (ii) the number of shares of common stock per Class A unit and the number of shares of Series B Convertible Preferred shares per Class
B unit; and (iii) the number of warrants per each Class A unit and Class B unit.

*        *        *
 *        *        *

 In the event that the Company
requests acceleration of the effective date of the Registration Statement, as amended, 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 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
 3

 We
hope that the foregoing, and the revisions to the Registration Statement, have been responsive to the Staff’s comments. If you have any questions concerning the foregoing, please do not hesitate to contact the undersigned at (415) 393-8373.

Very truly yours,

/s/ Ryan A. Murr

Ryan A. Murr

 Enclosures

cc:
Geert Cauwenbergh, Dr. Med. Sc., RXi Pharmaceuticals Corporation

November 4, 2016
Geert Cauwenbergh
President and Chief Executive Officer
RXi Pharmaceuticals Corp.
257 Simarano Drive
Suite 101
Marlborough, MA 01752
RXi Pharmaceuticals Corp.
Registration Statement on Form S-1
Filed October 21, 2016
File No. 333-214199Re:
Dear Dr. Cauwenbergh:
        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 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.
Registration Statement on Form S-1
Facing Page
In your Fee Table, please revise to calculate the registration fee of the units based on the
offer price of the units and the exercise price of the warrants, and calculate the fee of the
common stock underlying the warrants based on the exercise price of the warrants.  For
guidance, please refer to Securities Act Rules Compliance and Disclosure Interpretations
240.05 and 240.06, available on the Commission’s website.

 1.

Geert Cauwenbergh
RXi Pharmaceuticals Corp.
2 PageNovember 4, 2016
Cover Page
Although Rule 430A of the Securities Act of 1933 permits registrants to omit certain
pricing-related information from a registration statement that is declared effective, your
filing must include the amount of securities to be offered in a pre-effective amendment.
Accordingly, please confirm that you will revise your disclosure to specify: (i) the
number of each of the Class A units and Class B units to be offered; (ii) the number of
shares of common stock per Class A unit and the number of shares of Series B
Convertible Preferred shares per Class B unit; and (iii) the number of warrants per each
Class A unit and Class B unit.2.
       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 Joseph McCann, Staff Attorney, at (202) 551-6262 with any questions.
Division of Corporation Finance
Office of Healthcare and
Insurance

CORRESP
1
filename1.htm

Acceleration Request

 RXi Pharmaceuticals Corporation

257 Simarano Drive, Suite 101

Marlborough, MA 01752

April 17, 2014

 Via EDGAR
Transmission and E-Mail

 Securities and Exchange Commission

100 F Street, N.E.

 Washington, D.C. 20549

Attention: Jeffrey P. Riedler

 Johnny Gharib

Bryan J. Pitko

Re:
RXi Pharmaceuticals Corporation

 Registration Statement on Form S-3 (File
No. 333-194956)

 Ladies and Gentlemen:

Pursuant to Rule 461 promulgated under the Securities Act of 1933, as amended, RXi Pharmaceuticals Corporation (the
“Company”) hereby requests that its Registration Statement on Form S-3 (File No. 333-194956) (the “Registration Statement”), be declared effective at 4:00 p.m., Washington, D.C. time, on April 18, 2014, or
as soon thereafter as practicable.

 In connection with the acceleration of the declaration of effectiveness of the Registration Statement,
the Company hereby acknowledges that:

•

should the Securities and Exchange Commission (the “Commission”) or the staff of the Commission (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 direct any questions regarding this filing to Benjamin Kozik of Ropes & Gray LLP, counsel to the Company,
at (415) 315-6331.

 [Signature page follows]

Very truly yours,

RXI PHARMACEUTICALS CORPORATION

By:

 /s/ Geert Cauwenbergh

Geert Cauwenbergh, Dr. Med. Sc.

President and Chief Executive Officer

 Signature Page to Acceleration Request

April 3, 2014

Via E -mail
Geert Cauwenbergh, Ph.D.
President and Chief Executive Officer
RXi Pharmaceuticals Corporation
1500 West Park Drive, Suite 210
Westborough, Massachusetts 01581

Re: RXi Pharmaceuticals Corporation
  Registration Statement on Form S -3
Filed  April 1, 2014
  File No.  333-194956

Dear Dr. Cauwenbergh :

We have limited our review of your registration statement to the resolution of your
pending confidential treatment request.

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 th e 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 ha ve 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 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 fil ing 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 init iated 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

Geert Cauwenbergh, Ph.D.
RXi Pharmaceuticals Corporation
April 3, 2014
Page 2

 of the fact that those requesting acceleration are aware of their respective responsibilities under
the Securities Act of 1933 and th e 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
regist ration statement.

Please contact Johnny Gharib at (202) 551 -3170  or me at (202) 551 -3715  with any
questions.

Sincerely,

 /s/ Bryan J. Pitko for

 Jeffrey P. Riedler
Assistant Director

cc: Via E -mail
Ryan A. Murr, Esq.
 Ropes & Gray LLP

CORRESP
1
filename1.htm

Acceleration Request

 RXi PHARMACEUTICALS CORPORATION

1500 WEST PARK DRIVE, SUITE 210

 WESTBOROUGH, MA 01581

 August 6, 2013

Via EDGAR Transmission and E-Mail

U.S. Securities and Exchange Commission

Division of Corporate Finance

 100 F Street,
N.E.

 Mail Stop 6010

 Washington,
D.C. 20549

 Attn: Jeffrey P. Riedler

Re:
RXi Pharmaceuticals Corporation

 Registration Statement on Form S-1

 File No. 333-188539

 Dear Mr. Riedler:

 On behalf of RXi Pharmaceuticals Corporation (the “Company”), we hereby respectfully request that the Securities and Exchange Commission (the “Commission”) take
appropriate action to make the Company’s Registration Statement on Form S-1 effective on August 8, 2013 at 9:00 a.m. (Eastern time) or as soon thereafter as practicable, or at such later time as the Company may request by telephone to the
Commission. The Company hereby authorizes Ryan Murr or Lisa Kahle of Ropes & Gray LLP, counsel to the Company, to make such telephonic request on our behalf.

 In connection with the above-captioned Registration Statement, 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 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 proceedings initiated by the Commission or any
person under the federal securities laws of the United States.

 U.S. Securities and Exchange Commission

 Page 2

 Please direct any questions regarding this filing to Lisa Kahle at
(415) 315-6320.

Sincerely,

 /s/ Geert Cauwenbergh

Geert Cauwenbergh, Dr. Med. Sc.

President, Chief Executive Officer and Chief Financial Officer

cc:
Ryan A. Murr, Ropes & Gray LLP

 Lisa M. Kahle, Ropes & Gray LLP

May 22 , 2013

Via E -mail
Geert Cauwenbergh, Dr. Med. Sc.
President and Chief Executive Officer
RXi Pharmaceuticals Corporation
1500 West Park Drive, Suite 210
Westborough, MA 01581

Re: RXi Pharmaceuticals Corporation
  Registration Statement on Form S-1
Filed  May 10 , 2013
  File No.  333-188539

Dear Dr. Cauwenbergh :

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.

General

1. We are currently processing your  request s for conf idential treatment .  Please be advised
that we will not be in a position to declare this registration statement effective until we
resolve all issues concerning the pending confidential treatment request s.

2. Please either update your financial statements to reflect the most recent quarterly
financial results or revise the prospectus to specifically  incorporate by reference the Form
10-Q filed on May 15, 2013.  Please refer to Gen eral Instruction VII and Item 12 of Form
S-1 and  Question 113.05 of the Securities Act Forms Compliance a nd Disclosure
Interpretations for more information on incorporation by reference.

Geert Cauwenbergh, Dr. Med. Sc.
RXi Pharmaceuticals Corporation
May 22 , 2013
Page 2

 Selling Stockholders, page 23

3. Please e xpand this section to specifically state, if true, that at the time of the purchase of
the se curities to be resold, no selling stockholder  had any agreements or understandings,
directly or indirectly, with any person to distribute the securities.

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 effective, it does not foreclose the Commissi on 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 acc uracy 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 thei r 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 rev iew any amendment prior to the requested effective date of the
registration statement.

Geert Cauwenbergh, Dr. Med. Sc.
RXi Pharmaceuticals Corporation
May 22 , 2013
Page 3

 Please contact Austin Stephenson at (202) 551 -3192 , Bryan Pitko at (202) 551 -3203 , or
me at (202) 551 -3715 with any  questions.

Sincerely,

 /s/ Bryan J. Pitko for

 Jeffrey P. Riedler
Assistant Director

cc: Via E -mail
Ryan A. Murr , Esq.
Ropes & Gray LLP

CORRESP
1
filename1.htm

Correspondence

 July 5, 2012

 VIA EDGAR

 Securities and Exchange Commission

Division of Corporation Finance

 100 F Street,
N.E.

 Washington, D.C. 20549-4628

Re:
RXi Pharmaceuticals Corporation (the “Company”)

 Registration Statement on Form S-1

 Filed May 18, 2012

File No. 333-181534

Ladies and Gentlemen:

Pursuant to Rule 461 under the Securities Act of 1933, as amended, the undersigned registrant hereby requests that the effective
date of the above-referenced registration statement be accelerated so that it will be declared effective at 4:00 p.m. (Eastern) on Friday, July 6, 2012, or as soon thereafter as practicable.

In making this acceleration request, 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 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.

Sincerely,

By: RXi Pharmaceuticals Corporation

 /s/ Geert Cauwenbergh

Geert Cauwenbergh, Dr. Med. Sc.

President and Chief Executive Officer

cc:
Ryan Murr, Esq. (Ropes & Gray LLP)

CORRESP
1
filename1.htm

CORRESP

 June 21, 2012

 VIA EDGAR

 Jeffrey Riedler, Assistant Director

Jennifer Riegel, Special Counsel

 Nandini
Acharya, Staff Attorney

 Division of Corporation Finance

 Securities and Exchange Commission

 100 F Street, N.E.

Washington, D.C. 20549

Re:

RXi Pharmaceuticals Corporation

Registration Statement on Form S-1

Filed May 18, 2012

File No. 333-181534

 Ladies and Gentlemen:

 On behalf of RXi Pharmaceuticals Corporation (the “Company”), we are submitting to the Securities and Exchange Commission (the “Commission”) the Company’s response to the comment
from the staff of the Division of Corporation Finance (the “Staff”) contained in the comment letter from the Commission dated June 11, 2012 regarding the Company’s Registration Statement on Form S-1 (File No. 333-181534),
which was filed with the Commission on May 18, 2012 (the “Registration Statement”).

 The comment has been
reproduced below in italics, followed by the Company’s response. Capitalized terms used but not defined in this letter are intended to have the meanings ascribed to such terms in the Registration Statement.

1. Please provide us with your basis for determining that the transaction is appropriately characterized as a transaction that is
eligible to be made under Rule 415(a)(1)(i) rather than a primary offering. In your analysis, please address the following among any other relevant factors:

•

 The number of selling stockholders and the percentage of the overall offering made by each stockholder;

•

 The amount of shares involved;

Securities and Exchange Commission

- 2 -

June 21, 2012

•

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

•

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

•

 Any relationships among the selling stockholders;

•

 The discount at which the selling stockholders will purchase the common stock underlying the preferred stock upon conversion;

•

 Whether or not any of the selling stockholders is in the business of buying and selling securities; and

•

 Whether under all the circumstances it appears that the selling stockholders are acting as a conduit for the company.

 Alternatively, please name the selling stockholders as underwriters and register the offering on a registration
statement for which you are eligible to conduct a primary offering consistent with Rule 415. Please see our Compliance and Disclosure Interpretation 612.09 available at http://www.sec.gov/divisions/corpfin/guidance/securitiesactrules-interps.htm for
further guidance.

 Response to Comment 1:

 For the reasons set forth below, the Company respectfully submits that the offering to be registered pursuant to the Registration Statement is a valid secondary offering and may be registered as
contemplated by the Registration Statement, and that the selling stockholders are not “underwriters” within the meaning of Section 2(a)(11) of the Securities Act of 1933, as amended (the “Act”).

Background

 On September 24, 2011,
the Company entered into a Securities Purchase Agreement (the “Purchase Agreement”) with the two selling stockholders identified in the Registration Statement (the “Investors”), both of whom are accredited investors, for the sale
of 9,500 shares of Series A Convertible Preferred Stock (the “Preferred Stock”) for aggregate consideration of $9.5 million. This financing transaction pursuant to which the Preferred Stock was offered and sold is referred to herein as the
“Financing.” The Financing closed on April 27, 2012 (the “Closing Date”) following the registration under the Act of the distribution of shares of the Company’s common stock pursuant to a spin-out that was effected
through a dividend declared and paid by Galena Biopharma, Inc (“Galena”).

 The Preferred Stock was issued on the Closing Date
pursuant to the exemption from registration provided by Section 4(2) of the Act. In the Purchase Agreement, the Investors made customary representations and warranties regarding their investment intent, including representations that they were
purchasing their securities for their own accounts, for investment purposes and not for the purpose of effecting any distribution of the securities in violation of the Act.

Securities and Exchange Commission

- 3 -

June 21, 2012

 Preferred Stock Conversion Features

 Pursuant to the terms of the Certificate of Designations for the Preferred Stock (the “Certificate of Designations”), the Preferred Stock is convertible into common stock, par value $0.0001 per
share (the “Common Stock”), at a fixed conversion rate. The number of shares of Common Stock issuable upon conversion of the Preferred Stock is only subject to adjustment in the event of a stock split, reverse stock split or similar
recapitalization event. In no event is the conversion price for the Preferred Stock subject to adjustment based on future issuances of capital stock by the Company (i.e., there are no anti-dilution features). Additionally, the Preferred Stock is not
entitled to vote in the election of directors and generally has no voting rights, other than with respect to certain extraordinary events, such as an amendment to the rights, preferences or privileges of the Preferred Stock or any liquidation or
dissolution of the Company.

 The Preferred Stock is subject to a “blocker” provision contained in the Certificate of Designations,
which prevents the conversion of the Preferred Stock to the extent that the holder would, after conversion, beneficially own more than 9.999% of the Company’s issued and outstanding Common Stock. Accordingly, the selling stockholders will not,
by virtue of their ownership of the Preferred Stock and the Common Stock underlying the Preferred Stock (the “Conversion Shares”), beneficially own more than 9.999% of the Company’s voting securities. Of the total number of Conversion
Shares underlying the Preferred Stock, approximately 20% of the Conversion Shares are being registered for resale under the Registration Statement.

 Not a “Toxic” Financing

 The terms of the Financing do not include any conversion
price “re-sets”, floating price conversion rights or other “toxic” features that have historically prompted the Staff’s concerns regarding financing transactions that have sometimes been characterized as “extreme
convertible” transactions. The Certificate of Designations does not contain any conversion price adjustment mechanisms, including anti-dilution adjustments, other than customary adjustments that would apply in the case of a stock split, reverse
stock split and similar recapitalization event. Based on prior guidance provided by senior members of the Staff, the Company believes that the absence of any adjustment mechanisms would not raise concerns among the Staff with respect to the
Staff’s interpretation of Rule 415.

Securities and Exchange Commission

- 4 -

June 21, 2012

 Rule 415 Analysis

 In 1983, the Commission adopted Rule 415 under the Act to permit the registration of offerings to be made on a delayed or continuous basis. Rule 415 specifies certain conditions that must be met by an
issuer in order to avail itself of the Rule. In relevant part, Rule 415 provides:

 “(a) Securities may be
registered for an offering to be made on a continuous or delayed basis in the future, Provided, That:

 (1) The
registration statement pertains only to:

 (i) Securities which are to be offered or sold solely by or on behalf
of a person or persons other than the registrant, a subsidiary of the registrant or a person of which the registrant is a subsidiary;....[or]

 (x) Securities registered (or qualified to be registered) on Form S-3 or Form F-3 (§239.13 or §239.33 of this chapter) which are to be offered and sold on an immediate, continuous or delayed
basis by or on behalf of the registrant, a majority-owned subsidiary of the registrant or a person of which the registrant is a majority-owned subsidiary....”

 Under Rule 415(a)(1)(i), an issuer may register shares to be sold on a delayed or continuous basis by selling stockholders in a bona fide secondary offering without restriction.

In the event that an offering registered in reliance on Rule 415(a)(1)(i) is deemed to be an offering that is “by or on behalf of the
registrant” as specified in Rule 415(a)(1)(x), Rule 415 contains additional limitations. Rule 415(a)(4) provides that:

“In the case of a registration statement pertaining to an at the market offering of equity securities by or on behalf of the
registrant, the offering must come within paragraph (a)(1)(x) of this section. As used in this paragraph, the term ‘at the market offering’ means an offering of equity securities into an existing trading market for outstanding shares of
the same class at other than a fixed price.”

 As a result, if an offering that purports to be a secondary offering is characterized as an
offering “by or on behalf of the registrant,” Rule 415 is only available to register an “at the market offering” if the registrant is eligible to use Form S-3 or Form F-3 to register a primary offering.

In the event that the offering registered by the Registration Statement is recharacterized as a primary offering on behalf of the Company: (i) the
offering would have to be made on a fixed price basis (in other words, the Investors would not be able to sell their securities at prevailing market prices) unless the Company is eligible to use Form S-3 for a primary offering, (ii) the
Investors would be deemed to be “underwriters” with respect to the Financing (with the attendant liabilities under Section 11 of the Act), and (iii) in accordance with the Staff’s interpretive position, Rule 144 would not be
available to the Investors to effect resales of their securities.

 Because of the requirements of Rule 415, the Staff’s interpretation of
Rule 415 has a significant impact on the ability of a selling stockholder to sell the Common Stock registered on the Registration Statement. Because recharacterizing the offering as “by or on behalf of the registrant” has such a
significant impact, and a mischaracterization can have a chilling effect on the ability of

Securities and Exchange Commission

- 5 -

June 21, 2012

smaller public companies, such as the Company, to raise capital, the Company respectfully submits that the Staff should only recharacterize a secondary offering as being on behalf of a registrant
after a review of the relevant facts and circumstances, including the factors set forth in Interpretation 214.02 (the “Interpretation”) from the Staff’s Compliance and Disclosure Interpretations, which states that:

“It is important to identify whether a purported secondary offering is really a primary offering, i.e., the selling stockholders are
actually underwriters selling on behalf of an issuer. Underwriter status may involve additional disclosure, including an acknowledgment of the seller’s prospectus delivery requirements. In an offering involving Rule 415 or Form S-3, if the
offering is deemed to be on behalf of the issuer, the Rule and Form in some cases will be unavailable (e.g., because of the Form S-3 ‘public float’ test for a primary offering, or because Rule 415 (a)(l)(i) is available for secondary
offerings, but primary offerings must meet the requirements of one of the other subsections of Rule 415). The question of whether an offering styled a secondary one is really on behalf of the issuer is a difficult factual one, not merely a
question of who receives the proceeds. Consideration should be given to how long the selling stockholders have held the shares, the circumstances under which they received them, their relationship to the issuer, the amount of shares involved,
whether the sellers are in the business of underwriting securities, and finally, whether under all the circumstances it appears that the seller is acting as a conduit for the issuer.” (emphasis added)

As the Interpretation indicates, the question is a “difficult” and “factual” one that involves an analysis of many factors and
“all the circumstances.”

 Each of the relevant factors listed in the Interpretation is discussed below in the context of the
Financing. Based on a proper consideration of all of those factors, the Company believes that the Staff should conclude that the Registration Statement does relate to a valid secondary offering and that potentially all of the Conversion Shares can
be registered for sale on behalf of the Investors pursuant to Rule 415.

 How Long the Selling Stockholders Have Held the Shares

 Presumably, the longer shares are held, the less likely it is that the selling stockholders are acting as a mere conduit for the Company.
Here, the Investors have now held the shares (including the holding period for Preferred Stock, for which “tacking” would be permitted under Rule 144) for approximately two months as of the date of this letter (we further note that the
Investors became contractually obligated to purchase the Preferred Stock in September 2011, which is nearly nine months ago). Even this shorter two-month holding period is substantially longer than the period required by the Staff for valid
“PIPE” transactions.

Securities and Exchange Commission

- 6 -

June 21, 2012

 The Staff’s “PIPEs” interpretation is codified as Interpretation 139.11 (the “PIPEs
Interpretation”). The PIPEs Interpretation provides in relevant part that:

 “In a PIPE transaction, a company will be
permitted to register the resale of securities prior to their issuance if the company has completed a Section 4(2)-exempt sale of the securities (or in the case of convertible securities, of the convertible security itself) to the
investor, and the investor is at market risk at the time of filing of the resale registration statement.... The closing of the private placement of the unissued securities must occur within a short time after the effectiveness of the resale
registration statement.” (emphasis added)

 The PIPEs Interpretation contemplates that a valid secondary offering could be registered
under the Act prior to closing and that the resulting resale transactions could occur immediately following the closing of the initial private placement. Because no specific holding period is required for a PIPE transaction to be a valid
secondary offering, it stands to reason that a holding period of approximately two months must also be sufficient for a valid secondary offering.

 This conclusion comports with long-standing custom and practice in PIPE transactions, where investors require that a registration statement be filed shortly after closing (typically within 30 days) and
declared effective shortly thereafter (typically within 90 days from closing). Similar customary time periods apply in the case of the Financing.

 The Circumstances Under Which The Investors Received the Shares

 As described above, the
securities covered by the Registration Statement underlie the Preferred Stock, which was issued in a valid private placement that complied in all respects with the PIPEs Interpretation and Section 4(2) of the Act. As noted above, the
Certificate of Designations contains no “toxic” provisions or other terms that would be expected to merit any special concerns by the Staff. The Investors purchased their securities for investment and specifically represented that they
were not acquiring their securities with the purpose or intent of effecting a distribution in violation of the Act. There is no evidence to suggest that those representations are false and the Company respectfully submits that there is no basis for
concluding that the Investors do not have the intention or ability to hold their shares for investment purposes for an indefinite period. Based on reports of recent statements of policy of the Staff relating to Rule 415, the Company believes tha

June 11, 2012
   Via E-mail

Geert Cauwenbergh, Dr. Med. Sc.  President  RXi Pharmaceuticals Corporation  60 Prescott Street  Worcester, Massachusetts 01605
Re: RXi Pharmaceuticals Corporation
Registration Statement on Form S-1 Filed May 18, 2012
  File No. 333-181534

Dear Dr. Cauwenbergh:

We have reviewed your registration statem ent and have the following comment.  In
our comment, we ask you to provide us with  information so we may better understand your
disclosure.
 Please respond to this letter by amendi ng your registration statement and providing
the requested information.  If you do not beli eve our comment applies 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 re gistration statement and the information
you provide in response to this comment, we may have additional comments.
 FORM S-1

1. Please provide us with your basis for determining that the transaction is appropriately
characterized as a transaction that is eligible to be made under Rule 415(a)(1)(i) rather
than a primary offering. In your analysis, please address the following among any other
relevant factors:

 The number of selling stockholders and the percentage of the overall offering
made by each stockholder;

 The amount of shares involved;

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

Dr. Geert Cauwenbergh
RXi Pharmaceuticals Corporation June 11, 2012 Page 2
  The relationship of each selling stockholder with the company, including an
analysis of whether the selling stockholder is an affiliate of the company;

 Any relationships among the selling stockholders;

 The discount at which the selling stockholders will purchase the common stock
underlying the preferred stock upon conversion;

 Whether or not any of the selling stockholders is in the business of buying and
selling securities; and

 Whether under all the circumstances it appears that the selling stockholders are
acting as a conduit for the company.

Alternatively, please name the selling stockholders as underwriters and register the
offering on a registration statement for which you are eligible to conduct a primary
offering consistent with Rule 415.  Please see our Compliance and Disclosure Interpretation 612.09 available at
http://www.sec.gov/divisions/corpfin/guidance/s ecuritiesactrules-interps.htm for further
guidance.

We urge all persons who are responsible for the accuracy and adequacy of the
disclosure in the filing to be certain that th e filing includes the information the Securities Act
of 1933 and all applicable S ecurities Act rules require.  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.

Notwithstanding our comment, in the event you request acceleration of the effective
date of the pending registration statement pl ease provide a written statement from the
company acknowledging that:
 should the Commission or the staff, acting purs uant to delegated authority, declare the
filing effective, it does not foreclose th e 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 th e disclosure in the filing; and

 the company may not assert staff comments a nd 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 regard ing requests for acceleration.  We will
consider a written request for acceleration of th e effective date of th e registration statement
as confirmation of the fact that those request ing acceleration are aware of their respective

Dr. Geert Cauwenbergh
RXi Pharmaceuticals Corporation June 11, 2012 Page 3
 responsibilities under the Securi ties Act of 1933 and the Securiti es Exchange Act of 1934 as
they relate to the proposed public offering of th e 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 regist ration statement.
 Please contact Nandini Acha rya at (202) 551-3495, Jennife r Riegel, Special Counsel
at (202) 551-3575 or me at (202) 551-3715 with any other questions.

  Sincerely,
   /s/ Jennifer Riegel for
Jeffrey Riedler Assistant Director
  cc: Via E-mail

Ryan A. Murr, Esq.
Ropes & Gray LLP
Three Embarcadero Center
San Francisco, California 94111-4006

CORRESP
1
filename1.htm

corresp

February 13, 2012

VIA EDGAR

Securities and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549-6010

    Re:

    RXi Pharmaceuticals Corporation; Registration Statement on Form S-1 (Reg. No. 333-177498)

Ladies and Gentlemen:

     On behalf of RXi Pharmaceuticals Corporation (“RXi”), the undersigned hereby requests that the
Securities and Exchange Commission issue an order declaring the above-referenced Registration
Statement effective at 5:00 P.M., Washington, D.C. time, on Tuesday, February 14, 2012, or as soon
thereafter as is practicable.

     In making its request, RXi acknowledges that:

     1. Should the Commission or the staff, acting pursuant to delegated authority, declare the
Registration Statement effective, that act will 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 Registration Statement effective does not relieve RXi from its full responsibility
for the adequacy and accuracy of the disclosures in the Registration Statement; and

     3. RXi may not assert staff comments or 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.

     RXi also understands that this request for acceleration will be considered a confirmation of
its awareness of its obligations under the Securities Act of 1933 and the Securities Exchange Act
of 1934 with respect to the offering of securities pursuant to the Registration Statement.

Securities and Exchange Commission

February 13, 2012

Page 2

     Please call Dale Short (at 310-789-1259) of TroyGould PC as soon as the Registration Statement
has been declared effective.

Very truly yours,

/s/ Mark J. Ahn

Mark J. Ahn, Ph.D.

President

    Cc:

    Jeffrey P. Riedler (SEC)

Jennifer Riegel (SEC)

James Peklenk (SEC)

CORRESP
1
filename1.htm

corresp

TroyGould
pc

    1801 Century Park East, Suite 1600

    Los Angeles, California 90067-2367

    Tel (310) 533-4441
Fax (310) 201-4746

    www.troygould.com

Dale
Short • (310) 789-1259 • dshort@troygould.com

    File No. 3218-1

    February 7, 2012

BY EDGAR

James Peklenk

United States Securities and Exchange Commission

Division of Corporation Finance

100 F Street, N.E.

Washington, D.C. 20549

    Re:

    RXi Pharmaceuticals Corporation

Amendment No. 4 to Form S-1

Filed February 6, 2012

File No. 333-177498

Dear Mr. Peklenk:

     This letter and attachments respond to the oral comment of the staff (the
“Staff”) of the Securities and Exchange Commission (“SEC) communicated to me
earlier today regarding RXi Pharmaceuticals Corporation’s ( the “Company”) amended
Registration Statement on Form S-1/A filed on February 6, 2012. The Staff’s comment pertains to
the nature of the “derivatives potentially settleable in cash” liability (the “Derivative
Liability”) reflected on the “carved out” balance sheets of the Company contained in the amended
S-1/A. In this regard, please be advised supplementally that the actual liabilities of the Company
do not, and will not as of the completion of the spin-off of the Company, include the Derivative
Liability.

     The Derivative Liability as its description suggests is derived from the corresponding
“warrants potentially settleable in cash” liability of Galena Biopharma, Inc., the Company’s
current parent company (“Galena”), and management of the Company believe it is properly reflected
in the “carved out” financial statements of the Company for the reasons stated in the Company’s
previous response letters. By their nature, the “carved
out” financial statements reflect a pro forma
presentation and do not purport to be an actual depiction of the Company’s financial condition.

     As between Galena and the Company, only Galena is and will be
responsible for payment or other settlement of the Derivative
Liability. This is implicit in the
terms of the Contribution Agreement between Galena and the
Company, which Agreement provides, in Section 2.3 thereof, that the only liabilities of Galena
assumed by the Company are the “Assumed Liabilities” (as defined), which do not include the
Derivative Liability. Galena and the Company also have represented and warranted that this is the
case in the Securities Purchase Agreement

James Peklenk

February 7, 2012

Page 2

among Galena, the Company and Tang Capital Partners, LP and RTW
Investments, LLC refered to in the S-1/A.

     In response to the Staff’s comment, the Company hereby undertakes to make the changes shown on
the attached selected pages of the preliminary prospectus in order to clarify the treatment of the
Derivative Liability in connection with the spin-off. If these changes are acceptable, the Company
will file via EDGAR a pre-effective Amendment No.5 to the Form S-1 setting forth these changes, or
will include the changes in the final prospectus to be filed under Rule 424, if appropriate.

* * * * *

     Apart from the foregoing response to the Staff’s comments, the Company reiterates that it is
responsible for the accuracy and adequacy of the disclosures contained in the Registration
Statement.

     When the time comes, the Company will include in its request for acceleration of the
effectiveness of the Registration Statement the additional acknowledgements requested by the Staff.

     Please direct questions regarding this response letter to the undersigned at (310) 789-1259.

    Very truly yours,

    /s/ Dale E. Short

DES: tms

    cc:

    Mary Mast (SEC)

Jennifer Riegel (SEC)

     We recognize all derivatives as assets or liabilities measured at fair value with changes in
fair value of derivatives reflected as current period income or loss unless the derivatives qualify
for hedge accounting and are accounted for as such. During the period ended September 30, 2011 and the years ended December 31, 2010 and
2009, Galena issued derivatives to purchase 17,950,000, 540,000 and 978,142 shares of its common stock,
respectively, in connection with an equity transaction. In accordance with ASC Topic 815-40, “Derivatives and Hedging — Contracts in Entity’s Own Stock” (“ASC 815-40”), the value of these
derivatives is required to be recorded as a liability, as the holders have an option to put the
derivatives back to Galena in certain events, as defined.

     The
liability represents management’s best estimate of the Company’s allocable share of Galena’s warrants
issued as part of equity financings had the Company been a stand-alone
entity at the time. These warrants are
exercisable only for Galena common stock and are not exercisable for
RXi stock.
Upon the closing of the planned spin-off, the liability will
be a liability of Galena only, and will not be an obligation of the
Company.

Results of Operations for the Nine Months Ended September 30, 2011 and 2010

     For the nine months
ended September 30, 2011, our net loss was approximately $8,643,000 compared
with a net loss of $10,162,000 for the nine months ended September 30, 2010. Reasons for the variations in
the losses between the two periods are discussed below.

Results of Operations for the Years Ended December 31, 2010 and 2009

     For the year ended December 31, 2010, our net loss was approximately $11,993,000, compared
with a net loss of $18,387,000 for the year ended December 31, 2009. Reasons for the variations in
the losses between the years are discussed below.

     Revenues

     Since we are a development-stage biopharmaceutical company, we have not generated any revenues
since inception.

     Research and Development Expense (in thousands)

    For the Nine Months

     Ended September 30,

    2011

    2010

    Research and development expense

    $
    4,652

    $
    4,589

    Research and development employee stock-based compensation expense

    471

    814

    Research and development non-employee stock-based compensation expense

    (49
    )

    723

    Total research and development expense

    $
    5,074

    $
    6,126

    For the Years Ended

    December 31,

    2010

    2009

    Research and development expense

    $
    6,046

    $
    6,728

    Research and development employee stock-based compensation expense

    1,084

    867

    Research and development non-employee stock-based compensation expense

    743

    1,297

    Total research and development expense

    $
    7,873

    $
    8,892

     Research and development expense consists primarily of compensation-related costs for our
employees dedicated to research and development activities and for our Scientific Advisory Board
(“SAB”)
members as well as licensing fees, patent prosecution costs and the cost of lab supplies used
in our research and development programs. We expect to continue to devote a substantial portion of
our resources to research and development programs. We expect research and development expenses to
increase as we expand our research and development activities.

39

RXi PHARMACEUTICALS CORPORATION

(A Development Stage Company)

NOTES
TO FINANCIAL STATEMENTS

(Information as of September 30, 2011 and for the

nine months ended September 30, 2011 and 2010 is

unaudited)

     Derivative Financial Instruments — During the normal course of business, from time
to time, Galena issues warrants and options to vendors as consideration to perform
services. It may also issue warrants as part of a debt or equity
financing. The Company  does not enter into any derivative contracts for speculative purposes.

     The Company recognizes all derivatives as assets or liabilities measured at fair
value with changes in fair value of derivatives reflected as current period income or loss
unless the derivatives qualify for hedge accounting and are accounted for as such. In
accordance with FASB ASC Topic 815-40, “Derivatives and Hedging — Contracts in Entity’s
Own Stock,” the value of these derivatives is required to be recorded as a liability, as
the holders have an option to put the derivatives back to the Company
for cash upon the occurrence of
certain events set forth in the agreement.

     The
liability represents management’s best estimate of the Company’s allocable share of Galena’s warrants
issued as part of equity financings had the Company been a stand-alone
entity at the time. These warrants are
exercisable only for Galena common stock and are not exercisable for
RXi stock. Upon the closing of the planned spin-off, the liability will be
a liability of Galena only and will not be an obligation of the
Company.

     Obligations to Repurchase Shares of Galena’s Equity Securities — In accordance with
FASB ASC Topic 480-10, “Distinguishing Liabilities from
Equity,” the Company recognizes
all obligations to repurchase shares of Galena’s equity securities allocated to the
Company that require or may require settlement of the obligation by transferring assets,
as liabilities or assets in some circumstances measured at fair value with changes in fair
value reflected as current period income or loss and are accounted for as such.

     Deferred Revenue — Deferred revenue consists of advance payments received under government
grants. The Company will recognize revenue when the obligations under the grants are fulfilled.

     Research and Development Expenses — Research and development costs are expensed as
incurred. Included in research and development costs are wages, benefits and other
operating costs, facilities, supplies, external services and overhead directly related to
the Company’s research and development departments, as well as costs to acquire technology
licenses.

     Income Taxes — The Company recognizes liabilities or assets for the deferred
tax consequences of temporary differences between the tax basis of assets or liabilities
and their reported amounts in the financial statements in accordance with FASB ASC 740-10,
“Accounting for Income Taxes” (“ASC 740-10”). These temporary differences will result in
taxable or deductible amounts in future years when the reported amounts of the assets or
liabilities are recovered or settled. ASC 740-10 requires that a valuation allowance be
established when management determines that it is more likely than not that all or a
portion of a deferred asset will not be realized. RXi evaluates the realizability of its
net deferred income tax assets and valuation allowances as necessary, at least on an
annual basis. During this evaluation, the Company reviews its forecasts of income in
conjunction with other positive and negative evidence surrounding the realizability of its
deferred income tax assets to determine if a valuation allowance is required. Adjustments
to the valuation allowance will increase or decrease the Company’s income tax provision or
benefit. The recognition and measurement of benefits related to the Company’s tax
positions requires significant judgment, as uncertainties often exist with respect to new
laws, new interpretations of existing laws, and rulings by taxing authorities. Differences
between actual results and RXi’s assumptions or changes in the Company’s assumptions in
future periods are recorded in the period they become known.

     For the periods presented, RXi was not a separate taxable entity for federal, state,
and local income tax purposes and its operating results were included in Galena’s tax
returns. RXi calculated its income taxes under the separate return method and accounted
for deferred tax assets and liabilities under the asset and liability method described
above.

F - 11

RXi PHARMACEUTICALS CORPORATION

(A Development Stage Company)

NOTES
TO FINANCIAL STATEMENTS

(Information as of September 30, 2011 and for the

nine months ended September 30, 2011 and 2010 is

unaudited)

All options granted pursuant to the SAB
Agreements are fully vested on the date of grant and have a term of ten years. The fair
value of stock options granted during 2010 and 2009 under the SAB Agreement for each
founder is approximately $142,000 and $245,000 which was estimated using the Black-Scholes
option-pricing model as more fully discussed above under significant accounting policies
and the stock based compensation footnote. Included in the Company’s financial statements
for the years ended December 31, 2010 and 2009 is approximately $566,000 and $978,000,
respectively, of expense related to the granting of these stock options. Included in the Company’s
financial statements for
the nine months ended September 30, 2010 is approximately $566,000, of expense related to the granting of these stock options.
No options under the SAB agreements were issued during the nine months
ended September 30, 2011.

     Additionally, pursuant to a letter agreement between Galena and each founder dated as
of April 30, 2007, the “SAB Letters”, in further consideration of the services to be
rendered by the founders under the SAB Agreements, Galena granted additional stock options
on May 23, 2007 under the 2007 Plan to each of the founders to purchase 26,416 shares of
its common stock. Unless a founder terminates a SAB Agreement without good reason (as
defined) or the Company terminates a SAB Agreement with cause (as defined therein), the
options granted pursuant to the SAB Letters will fully vest from and after April 29, 2012
and will have a term of ten years from the date of grant. At September 30, 2011 and December
31, 2010, the fair market value
of stock options under the SAB Agreement for each founder is
approximately $52,400
and $20,500, respectively, which was estimated using the Black-Scholes option-pricing
model as more fully discussed above under the summary of significant accounting policies
and the stock based compensation footnote. Included in the Company’s financial statements
for the nine months ended September 30, 2011 and the years ended December 31, 2010 and 2009 is
approximately $125,000 and $38,000 of income and $73,000, of expense, respectively,
related to these stock options.

12. Subsequent Events

     In accordance with ASC 855-10, Subsequent Events, management has evaluated subsequent
events through to the date these financial statements are filed. The Company did not have any material recognizable or unrecognizable
subsequent events, except the following:

     On December 6, 2011, Galena entered into separate exchange agreements with several institutional
 holders of outstanding warrants to purchase shares of Galena common stock at an exercise price of $0.65 per share.
 The warrants were originally issued by Galena in its underwritten offering completed in April 2011. In the exchange agreements,
 the warrant holders collectively have agreed to surrender to Galena for cancellation, warrants to purchase an aggregate of 5,930,00
 shares of Galena common stock in exchange for an aggregate of 4,151,000 shares of Galena common stock. The closing of the exchange occurred on December 6, 2011. The exchange is expected to result in the elimination of approximately $2.5 million of fair value of derivatives potentially settleable in
 cash reflected on our balance sheet as of September 30, 2011.
All of the remaining outstanding warrants are exercisable
only for Galena common stock, and are not exercisable for
the Company common stock. Upon the
closing of the planned spin-off, the liability will be a liability of
Galena only and will not be an obligation of
the Company.

F - 30

January 31, 2012
  Via E-mail

Dr. Mark J. Ahn, Ph.D. President  RXi Pharmaceuticals Corporation 60 Prescott Street Worcester, MA 01605

Re: RXi Pharmaceuticals Corporation
Amendment No. 3 to Form S-1 Filed January 23, 2012
  File No. 333-177498

Dear Dr. Ahn:

We have reviewed your amended registra tion statement and response letter each
filed on January 23, 2012 and have the following comments.  In some of our comments, we may ask you to provide us with info rmation so we may better understand your
disclosure.
 Please respond to this letter by am ending 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 amendment is appropriate, please tell us why
in your response.
 After reviewing any further amendments to your registration statement and the
information you provide in response to th ese comments, we may have additional
comments.

Financial Statements
Notes to Financial Statements
8. Stock-based Compensation
2011 Offerings, page F-24

1. Please refer to your response to comment 2.  You state that the April 2011 warrant
liability was allocated to RXi’s financial st atements “based on the expected use of
the offering proceeds at the time the offering was completed, rather than on the basis of whether the proceeds were subse quently used for RXi’s operations.”  It
appears that RXi did not receive any of  the April 2011 offering proceeds and thus

Dr. Mark J. Ahn
RXi Pharmaceuticals Corporation January 31, 2012 Page 2
 received no consideration for the 50% al location of the warrant liability.  We
continue to question why you believe it is  appropriate to record the derivative
relating to the April 2011 offeri ng in the historical financial statements of RXI.  In
addition, you state that at the time of the March 2011 offering, “Galena operated
only one business, the RNAi business.  It was not until the Apthera acquisition that occurred on April 13, 2011, that Gale na operated a business other than the
RNAi business”.  Thus, you have allocated  100% of the warrant  liability related
to the March offering to RXi’s financial st atements.  However, at the time of the
Apthera acquisition it appears that the offering proceeds should have been reallocated to the business in which the pr oceeds were to be used.  In preparing
the financial statements for RXI’s spin-off, amounts that are specifically applicable to a subsidiary should be r ecorded in the subsidiary’s financial
statements.  In absence of specific iden tification, a reasonable  allocation may be
made.  As it appears that the proceeds from  the March offering were not used for
the business of RXI, it is not clear why a llocating the warrant liability associated
with the offering is reasonable.   Pleas e refer to the guidance in SAB 103 Topic
1.B.1.
 12. Subsequent Events, page F-30

2. Please disclose your intended accounting treatment for the exchange of warrants
for Galena stock and the elimination of the fair value of $2.5 million of warrant
derivatives on your balance shee t.  Clarify in the filing if the warrants associated
with the March and April offerings will continue to be exercisable for Galena common stock after the spin-off and not RX I common stock.  In addition, please
confirm to us that the shares after distri bution in “Results of Distribution” on page
30 include the shares as a result of the exchange of warrants for Galena stock in
December 2011.
 Exhibits

3. Please revise Exhibit 3.1 to file the fina l dated and signed vers ion of your current
amended and restated certificate of incorporation.

4. Please file a copy of your form of amendm ent to the certificate of incorporation
that will be filed with the Secretary of St ate of Delaware prior to the distribution.
Please also confirm that you will file a c opy of the final amendment after it has
been filed with the Secretary of State of Delaware.

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 1933 and all applicable Securities Act rules require.  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.

Dr. Mark J. Ahn
RXi Pharmaceuticals Corporation January 31, 2012 Page 3
 Notwithstanding our comments, in the ev ent you request acceleration of the
effective date of the pending registration st atement please provide a written statement
from the company acknowledging that:
 should the Commission or the staff, acti ng 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 disclo sure in the filing; and

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

Please refer to Rules 460 and 461 regard ing requests for acceleration.  We will
consider a written request for acceleration of  the effective date of the registration
statement as confirmation of th e fact that those requesting acc eleration are aware of their
respective responsibilities unde r the Securities Act of 1933 a nd the Securities Exchange
Act of 1934 as they relate to the proposed public  offering of the securi ties specified in the
above registration statement.  Please allo w adequate time for us to review any
amendment prior to the requested effective da te of the registration statement.
 You may contact James Pekl enk at (202) 551-3661 or Mary Mast at (202) 551-
3613 if you have questions regarding comments on the financial statements and related
matters.  Please contact Jennifer Riegel, Sp ecial Counsel, at (202) 551- 3575 or me at
(202) 551-3715 with any other questions.
 Sincerely,
   /s/ Jennifer Riegel for   Jeffrey Riedler
Assistant Director
   cc: Dale E. Short, Esq.  TroyGould PC    1801 Century Park East, Suite 1600     Los Angeles, CA 90067-2367

January 10, 2012
  Via E-mail

Dr. Mark J. Ahn, Ph.D. President  RXi Pharmaceuticals Corporation 60 Prescott Street Worcester, MA 01605

Re: RXi Pharmaceuticals Corporation
Amendment No. 2 to Form S-1 Filed December 29, 2011
  File No. 333-177498

Dear Dr. Ahn:

We have reviewed your amended regist ration statement and response letter each
filed on December 29, 2011 and have the following comments.  In some of our comments, we may ask you to provide us w ith information so we may better understand
your disclosure.
 Please respond to this letter by am ending 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 amendment is appropriate, please tell us why
in your response.
 After reviewing any further amendments to your registration statement and the
information you provide in response to th ese comments, we may have additional
comments.    General

1. Please revise your filing to complete the missing disclosure concerning share
numbers and the disclosure concerning your  stock split.  Please also revise
your Exhibit 3.1 to include the complete certificate of incorporation, as filed
with the Secretary of State of Delaware.

Dr. Mark J. Ahn
RXi Pharmaceuticals Corporation January 10, 2012 Page 2
 Financial Statements

Notes to Financial Statements
12. Subsequent Events, page F-30
2. Please refer to your response to comme nt 11.  You state on page F-24 with
respect to the thirteen month warrants and the five year warrants issued in the March 2011 offering that the fair va lue of the remaining 2,550,000 warrants
totaling $1,790,000 was recorded as a deri vative liability in RXI’s financial
statements.  You state on page F-25 with respect to the April 2011 offering,
including the warrants issued in excha nged for the March 2011 warrants, that
a portion of the liability was allocated to RXI based on the expected offering
proceeds.  Based on the disclosure in the filing and your response you allocated 100% of the warrant liabil ity relating to the remaining March
warrants (after the exchange) to RXI a nd 50% of the warrant liability for the
April issuance, including the March exch ange warrants to RXI.  We note that
RXI had a cash balance of  $6.891 million at December 31, 2010 and that cash
used in the nine months ending September 30, 2011 was $6.469 million which resulted in a cash balance of $422,000 at  September 30, 2011.  As it is not
clear that any of the offering proceed s were allocated to the historical
operations of RXI, please tell us why you believe it is appropriate to record
the derivative relating to the March and April 2011 offerings in the historical
financial statements of RXI.  We note in the Statement of Cash Flows that
Galena contributed $369,000 to RXI in the nine months ended September 30,
2011.  Please tell us if that  contribution was part of the agreement to loan up
to $1.5 million to RXI as part of the spin-off.

Exhibit 5.1

3.  Please expand this opinion to disclose  the number of shares of common stock
included in this opinion.  Please also c onfirm that this amount is consistent
with the amount of securities being regi stered on this registration statement.
4. Please revise this opinion to remove a ssumptions (3) and (4) contained in the
last paragraph of the first page of this  opinion.  See Secti on II.B.3.a of Staff
Legal Bulletin 19.

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 1933 and all applicable Securities Act rules require.  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.

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

Dr. Mark J. Ahn
RXi Pharmaceuticals Corporation January 10, 2012 Page 3
  should the Commission or the staff, acti ng 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 disclo sure in the filing; and

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

Please refer to Rules 460 and 461 regard ing requests for acceleration.  We will
consider a written request for acceleration of  the effective date of the registration
statement as confirmation of th e fact that those requesting acc eleration are aware of their
respective responsibilities unde r the Securities Act of 1933 a nd the Securities Exchange
Act of 1934 as they relate to the proposed public  offering of the securi ties specified in the
above registration statement.  Please allo w adequate time for us to review any
amendment prior to the requested effective da te of the registration statement.
 You may contact James Pekl enk at (202) 551-3661 or Mary Mast at (202) 551-
3613 if you have questions regarding comments on the financial statements and related
matters.  Please contact Jennifer Riegel, Sp ecial Counsel, at (202) 551- 3575 or me at
(202) 551-3715 with any other questions.

Sincerely,
   /s/ Jennifer Riegel for   Jeffrey Riedler
Assistant Director
   cc: Dale E. Short, Esq.  TroyGould PC    1801 Century Park East, Suite 1600     Los Angeles, CA 90067-2367

December 22, 2011
 Via E-mail

Dr. Mark J. Ahn, Ph.D. President  RXi Pharmaceuticals Corporation 60 Prescott Street Worcester, MA 01605

Re: RXi Pharmaceuticals Corporation
Form S-1/A Filed December 8, 2011
  File No. 333-177498

Dear Dr. Ahn:

We have reviewed your amended regist ration statement and response letter each
filed on December 8, 2011 and have the followi ng comments.  In some of our comments,
we may ask you to provide us with info rmation so we may better understand your
disclosure.
 Please respond to this letter by am ending 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 amendment is appropriate, please tell us why
in your response.

After reviewing any further amendments to your registration statement and the
information you provide in response to th ese comments, we may have additional
comments.    FORM S-1/A

 Cover Page

1. In response to prior comment 8, you disclose that you are in the process of
applying for trading of your common stock in the OTC Markets Group.  We
are re-issuing our prior comment.  Pleas e disclose here and on pages 31 and
73 whether you have filed an application fo r listing.  If an application has not
been filed, please disclose when you intend to do so.

Dr. Mark J. Ahn
RXi Pharmaceuticals Corporation December 22, 2011 Page 2

Plan of Distribution

Reasons for the Distribution, page 28

2. We note your response to prior comme nt 20, in which you bullet-point and
clearly discuss each of the potential bene fits of the separation from Galena.
Please expand your disclosure of the ne gative factors of the separation from
Galena to similarly present each factor considered.
 Business, page 46

Introduction to the Field of RNAi Therapeutics, page 48
3. We note your response to our prior comment 28 and your citation of the
National Review of Drug Discovery in s upport for the statement referenced in
our comment.  Please provide additiona l factual support.  For example, was
there a particular study cited in the Na tional Review of Drug Discovery that
supports your assertion?  If so, please revise your di sclosure to describe the
study and its material  findings.

License Agreements, page 54
4. We note your response to our prior co mment 31.  While we are reviewing
your request for confidential treatment and may grant conf idential treatment
for the specific royalty percentages, please revise your disclosure in the
registration statement to include a range of royalty payments not to exceed ten
percent as we believe these are material terms of the agreement.
5. We note your response to our prior co mment 32.  While we are reviewing
your request for confidential treatment and may grant conf idential treatment
for the specific milestone payments a nd specific royalty percentages set forth
in the license agreement with Dharmac on, Inc., please revise your disclosure
in the registration statement to incl ude the potential aggregate milestone
payments and a range of royalty payments not to exceed ten percent as we believe these are material terms of the agreement.
Management, page 59

6. In response to prior comment 34, you disclose that Dr. Ahn serves on a part-
time basis as your President and Chief Financial Officer.  We are re-issuing
our comment to request th at you disclose here and on pages 11, 59 and 66 the
number of hours, on a monthly or weekly  basis, that Dr. Ahn expects to work
in this capacity.

Dr. Mark J. Ahn
RXi Pharmaceuticals Corporation December 22, 2011 Page 3
 Executive Compensation, page 61

7. Please confirm that you will update your executive compensation disclosure
for 2011 in any amendment filed on or after January 1, 2012.

Certain Relationships and Relate d Party Transactions, page 65
8. Please provide us with an analysis th at supports your conclusion that you are
not substantially dependent on your agreements with Northwestern University and Carnegie Institute of Washington. Alternatively, please file the license
agreements as exhibits to your filing a nd describe the material terms of any
such agreements in your Business se ction, including, but not limited to any
payment provisions, aggregate milestone payments, a range of royalty payments, exclusivity provisions, material obligations that must be met to keep the agreement in place, duration and termination provisions.

Beneficial Ownership of Certain Bene ficial Owners and Management, page 68

9. We note your response to prior comment 37.  It appears that footnotes (2) and
(4) also apply to the After the Spin-O ff Transaction Percentage columns for
Mr. Tang, Mr. Wong, Tang Capital Partne rs and RTW Investments. Please
revise your table accordingly.

Financial Statements
Notes to Financial Statements
1. Nature of Business, page F-8
10. You state that “management belie ves the assumptions underlying the
allocations of indirect expenses in the carve-out financial information are
reasonable; however, RXi’s financial pos ition, results of operations, and cash
flows may have been materially differe nt if it had operate d as a stand-alone
entity as of and for nine months e nded September 30, 2011”.  Please tell us
what is meant by the last statement a nd why the statement only relates to the
nine months ended September 30, 2011 and not to the two years ended December 31, 2010.

12. Subsequent Events, page F-30

11. You state that on December 6, 2011 Galena  entered into a transaction with
warrant holders in which Galena stock will be issued in exchange for cancellation of warrants.  The warrants we re issued in the April 2011 offering.
As a result of this transaction, the de rivatives recorded in RXI’s financial
statements will be reduced.  Please clar ify to us what the proceeds of the 2011
offerings were used for and where th ey are reflected in RXI’s financial

Dr. Mark J. Ahn
RXi Pharmaceuticals Corporation December 22, 2011 Page 4
 statements.  If the proceeds were not used  for the historical operations of RXI,
please tell us why the warrants relati ng to the offerings are included as
derivatives in the financial statements of RXI.

Exhibits

12. We have reviewed your response to prior comment 38.  Please confirm that
prior to requesting acceleration of this  registration statement, if you are
required to obtain prior written consent of a counterparty prior to the assignment and transfer, you will disclo se the name of all counterparties
which consent is required and has not been obtained and the effect of not
obtaining such consent.

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 1933 and all applicable Securities Act rules require.  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.

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

 should the Commission or the staff, acti ng 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 disclo sure in the filing; and

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

Please refer to Rules 460 and 461 regard ing requests for acceleration.  We will
consider a written request for acceleration of  the effective date of the registration
statement as confirmation of th e fact that those requesting acc eleration are aware of their
respective responsibilities unde r the Securities Act of 1933 a nd the Securities Exchange
Act of 1934 as they relate to the proposed public  offering of the securi ties specified in the
above registration statement.  Please allo w adequate time for us to review any
amendment prior to the requested effective da te of the registration statement.

Dr. Mark J. Ahn
RXi Pharmaceuticals Corporation December 22, 2011 Page 5
 You may contact James Pekl enk at (202) 551-3661 or Mary Mast at (202) 551-
3613 if you have questions regarding comments on the financial statements and related
matters.  Please contact Nandini Acharya at (202) 551-3495, Jennifer Riegel, Special
Counsel, at (202) 551- 3575 or me at (202) 551-3715 with any other questions.

 Sincerely,
   /s/ Jennifer Riegel for    Jeffrey Riedler
Assistant Director

Via E-mail

cc: Dale E. Short, Esq.  TroyGould PC    1801 Century Park East, Suite 1600     Los Angeles, CA 90067-2367

November 21, 2011
  Via E-mail

Dr. Mark J. Ahn, Ph.D. President  RXi Pharmaceuticals Corporation 60 Prescott Street Worcester, MA 01605

Re: RXi Pharmaceuticals Corporation
Form S-1 Filed October 25, 2011
  File No. 333-177498

Dear Dr. Ahn:

We have reviewed your registration stat ement and have the following 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 am ending 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 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 th ese comments, we may have additional
comments.    FORM S-1

 General

1. We note that you have submitted a numb er of documents in a confidential
treatment request.  Please note that you will be receiving comments to the confidential treatment reque st under separate cover a nd that all c onfidential
treatment issues must be resolved before we will consider a request for acceleration of the re gistration statement.

Dr. Mark J. Ahn
RXi Pharmaceuticals Corporation November 21, 2011 Page 2

2. Please provide updated interim financia l statements and related financial
information for the period ending September 30, 2011, pursuant to Rule 3-01 and 3-12 of Regulation S-X.  Please al so file an updated, signed consent
report from your independent audito rs prior to going effective.

3. Please note that before we will declare the registration statement effective,
you must revise your filing throughout to  include any omitted information that
is currently denoted by blanks.

4. Please note that where we provide exampl es to illustrate what we mean by our
comments, they are examples and not complete lists.  If our comments are applicable to portions of the filings that  we have not cited as examples, please
make the appropriate changes in accordance with our comments.
5. We note that the tax opini on, legal opinion and related consents have not been
filed.  Please file them as soon as pract icable, as we will need time to review
this exhibits once they have been filed.

6. In several places in the registration statement, you cite various estimates,
statistics and other figures.  For example:

a. The statement that “Approximately 42 million surgical procedures are
performed annually…” which is  found on pages 1 and 46; and
b. The statement that “Numerous studies implicate CTGF overexpression in
scarring…” which is found on pages 1 and 46.
In the prospectus, please attribute these statements and other similar
statements to the source from which you obtained the information. In addition,
where you cite your own estimates, pleas e explain how you arrived at those
estimates and disclose any thir d-party sources you relied upon.

7. Throughout the registration statement, you should clearly articulate the basis
of the various beliefs and assertions you make.  As a non-exclusive example,
on pages 1 and 35, you state, “We belie ve that RXI-109 or other CTGF-
targeting compounds may be able to  treat other indications, including
pulmonary fibrosis, liver fibrosis, acut e spinal injury, ocular scarring and
restenosis.” As another example, on pa ge 49, you state, “The specificity of
RNAi may be sufficient to permit th erapeutic targeting…and…may even
selectively reduce or eliminate expre ssion…” If you haven’t done so, please
clarify whether the relevant statement is your belief or opinion.  In addition,
please disclose the basis for your belief.  If any of your assertions of beliefs
are not supported by ample evidence or  knowledge, you should delete them.

Dr. Mark J. Ahn
RXi Pharmaceuticals Corporation November 21, 2011 Page 3
 Cover Page

8. You disclose that following the comp letion of the distri bution, you anticipate
that your common stock will trade in the OTC Markets Group under the symbol [“RXII.”]  Please revise your disclosure he re and on pages 31 and 73
to clarify whether you have filed an app lication for listing.  If an application
has not been filed, please disclo se when you intend to do so.

Table of Contents, page i

9. You state that “We have not independently  verified any of this [data derived
from third-party sources] and cannot  assure you of its accuracy or
completeness.” Please delete this statement as it is not appropriate to disclaim or imply that you are not taking liability for the statements in your registration
statement.   Alternatively, please expand your disclosure to include a
statement specifically accepting lia bility for these statements.

Prospectus Summary, page 1

10. You disclose on page 42 that you have  not generated revenue to date and
may not generate product revenue in the foreseeable future, if ever.
Furthermore, you expect to incur sign ificant operating losses as you advance
your product candidates through the drug development and regulatory
process.  Please expand your disclosure  under “Our Business” to clarify to
disclose this information.

Risk Factors, page 11
11. On page 57, you note that your research  and development activities involve
the controlled use of potentially harm ful biological materials as well as
hazardous materials, chemicals and va rious radioactive compounds.  Please
consider whether you should include a risk  factor that addresses the resulting
risks to you and your business as a result of your use of these materials.

“We may be unable to achieve some or all of  the benefits that we expect…,” page 11
12. You disclose that you may not be able to obtain approval from one or more
granting institutions to Galena’s assi gnment to you of approximately $800,000
of research grants.  Please disclose  whether you are aw are of any granting
institution that has indicate d that it will not consent to the assignment of the
respective grant.

Dr. Mark J. Ahn
RXi Pharmaceuticals Corporation November 21, 2011 Page 4
 “We may be unsuccessful in recruiting a Chief Executive Officer…,” page 11

13. You disclosed that you will need to recr uit and hire a Chief Executive Officer
to replace Mark J. Ahn, Ph.D., who currently serves as our President and Chief Financial Officer, and other ex ecutive officers and key employees.
Please expand your disclosure to list a ll the executive officers you are seeking
to recruit and hire.  For example, are you also seeking to recruit and hire a
Chief Financial Officer?

“We will be subject to competition and ma y not be able to compete...,” page 15

14. Please clarify the diseases you are targe ting which are also being targeted by
your competitors.

“We may be unable to protect  our intellectual property rights licensed from other
parties…,” page 16
15. Please expand your disclosure to disclose the name of the third party that sent
you a letter claiming that you require acce ss to such third party’s patent and
patent applications and demanding th at you stop engaging in unspecified
alleged infringing activities unless you obt ain a license from such third party
as this appears to be information that  may be material to your business.

“Our success depends upon our ability to obtain and maintain intellectual property
protection...,” page 17
16. Please disclose whether there are any other entities which currently have
legally blocking proprietary ri ghts of which you are aware.

“We will rely upon third parties for the manufa cture of our clinical product.” page 17
17. Please disclose whether there are an y third-party manufacturers upon which
you are substantially dependent.   Plea se file the related agreements as
exhibits to your filing and describe the material terms of any such agreements
in your Business section, including, but not limited to any payment provisions,
exclusivity provisions, material obliga tions that must be met to keep the
agreement in place, duration and termination provisions.

“If we fail to attract, hire and re tain qualified personnel...,” page 20
18. To the extent that you have experience d difficulties attracting and retaining
key personnel, please revise to discu ss these difficulties.  Also, disclose
whether any key personnel have plans to  retire or leave your company in the
near future.

Dr. Mark J. Ahn
RXi Pharmaceuticals Corporation November 21, 2011 Page 5
 “You may have difficulty selling our shares of common stock if they are deemed “penny
stocks.”  page 22
19. Please clarify whether you believe that your common stock will be deemed a
“penny stock.”

Plan of Distribution, page 28
 Reasons for the Distribution, page 28

20. Please expand this section to describe in  more detail the negative factors and
potential benefits the Galena board cons idered in evaluati ng the separation of
RXi from Galena.
21. Please clarify whether you are responsible for the entire cost of the fees and
expenses disclosed on the top of page 29, as we note that you have agreements
related to the reimburseme nt of transaction costs as described on page 30.

Trading Market, page 31
22. You state on page 32, “These are just so me of the factors that may adversely
affect the market price of our common stock.”  Please confirm that you have
described all material fact ors likely to adversely impact the market price of
your common stock or revise the disclo sure to include additional material
factors.

Trading Between the Record Date  and Distribution Date, page 32
23. Please confirm that your record date w ill be after the eff ectiveness of this
registration statement.  Alternativel y, please provide us with a detailed
analysis which supports your conclusion that the “when-issued” trading is
consistent with Section 5 of the Securities Act of 1933.

Management’s Discussion and Analysis of Fi nancial Condition and Results of Operations
 Liquidity and Capital Resources, page 42

24. You disclose that you had cash and cas h equivalents of approximately $1.9
million as of October 15, 2011.  Please cl arify whether this includes the $1.5
million contribution by Galena wh ich you disclosed on page 30.

Dr. Mark J. Ahn
RXi Pharmaceuticals Corporation November 21, 2011 Page 6
 Business, page 46

25. Please clarify which human diseases or  types of human diseases you believe
can be potentially treated by silencing ta rgeted genes that lead to disease
together with your basis for such belief.

Recent Business Developments, page 47
26. In each discussion of the initial results of your preclinical research and data
please clarify if there was a specific duration in which the silencing was
experienced.  In this regard, we notice your reference to one week on page 1.
27. In the third bullet point you note that th e collaboration demonstrated efficacy.
Please revise your disclosure to cl arify what you mean by “demonstrated
efficacy” as it does not appear to be appr opriate to use this term in reference
to a pre-clinical  collaboration.

Introduction to the Field of RNAi Therapeutics, page 48
28. Please characterize as your belief or opinion the statement that “The
specificity of RNAi may be sufficient to permit therapeutic targeting…and…may even selectively reduce or eliminate expression…”
Alternatively, provide additional fact ual support for this assertion.

Patents and Patent Applications, page 54

29. In this section, you refere nce both patents and patent applications, but you
appear to only discuss your material patent applications.  Please expand your
disclosure in this section to also di scuss any material patents, including for
each patent or group of patents the tec hnology to which the patent relates and
the expiration date of the patent.
30. Please clarify if you have any patents or patent applications  in jurisdictions
outside the United States.

License Agreements, page 54
31. Please disclose the aggregate milest one payments you are required to pay
under the license agreement with the University of Massachusetts Medical
School.

Dr. Mark J. Ahn
RXi Pharmaceuticals Corporation November 21, 2011 Page 7
 32. Please disclose the aggregate clinical milestone payments and a range of
royalty payments (not to exceed ten per cent) under the license agreement with
Dharmacon, Inc.
33. For each of the license agreements below,  please provide us with an analysis
that supports your conclusion that you ar e not substantially dependent on the
following agreements disclosed on page F-28:
 License agreement with Cold  Spring Harbor Laboratory;
 License agreement with TriLink Biotechnologies;
 License agreement with Life Technologies; and
 License agreements with University  of Massachusetts Medical School,
other than the license  agreement already disclosed on page 54.

Alternatively, please file th e license agreements as exhibits to your filing and
describe the material terms of any su ch agreements in your Business section,
including, but not limited to any pa yment provisions, aggregate milestone
payments, a range of royalty payments , exclusivity provisions, material
obligations that must be met to keep  the agreement in place, duration and
termination provisions.
 Management, page 59

34. We note that Mark Ahn also serves as the President, Chief Executive Officer
and a director of Galena.  Please expa nd your disclosure here and on page 66
to disclose the number of hours Mr. Ahn has agreed to dedicate to you.  Please
also consider adding a risk factor to discuss the risks that  your President and
Chief Financial Officer is not working full time for you, is not being compensated by you and may have conflicts of interests with you.

Certain Relationships and Relate d Party Transactions, page 65

 Agreements with Galena Biopharma, Inc., page 65

35. Here, and in the Business section as a ppropriate, please disclose the names of
the institutions which granted the resear ch grants and the license agreements
that Galena has assigned to you in  connection with the contribution
agreement.

Advirna Agreement, page 66
36. Please disclose the exact nature of the affiliation between Advirna and
Anastasia Khvorova.

Dr. Mark J. Ahn
RXi Pharmaceuticals Corporation November 21, 2011 Page 8
 Beneficial Ownership of Certain Bene ficial Owners and Management, page 68

37. Although we note that there is a “conve rsion cap” limitation for certain of
your investors, the security holders’ abili ty to acquire and sell a large amount
of your common stock is material in formation which is required to be
disclosed in your registration statem ent. See Securities Act Rule 408.
Accordingly, please revise your tabl e to include the ownership of Tang
Capital Partners, RTW Investments,  Mr. Tang and Mr. Wong without
consideration of the “conve rsion limitation.”  In a ddition, please include a
footnote to your beneficial ownershi p table that discloses the “conversion
limitation” and the impact on the respective security holders.

Exhibits
38. We note that Exhibits 2.1 and 2.2 each omit various schedules and exhibits
thereto.   Please either file complete c opies of these agreements or provide us
with a detailed analysis of each omitte d schedule, exhibit or other attachment
thereto that supports your belief th at such schedule does not contain
information which is material to an in vestment decision or which is otherwise
disclosed in the agreement or the filing and provide us copies of each omitted
schedule, exhibit or other attachment th ereto. In addition, please re-file each
agreement with a list briefly identifying the contents of all omitted schedules, together with an agreement to furnish supplementally a copy of any omitted
schedule to the Commission upon request.  See Item 601(b)(2) of Regulation
S-K.

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 1933 and all applicable Securities Act rules require.  Sinc