SecProbe.io

CORRESP
 1
 filename1.htm

 nrxp20251218_corresp.htm

 NRx Pharmaceuticals, Inc.
 1201 Orange Street, Suite 600
 Wilmington, DE 19801

 December 18, 2025

 VIA EDGAR

 United States Securities and Exchange Commission

 Division of Corporation Finance

 100 F Street, N.E.

 Washington, D.C. 20549

 Attention: Jason Drory

 Re:

 NRx Pharmaceuticals, Inc.

 Registration Statement on Form S-3/A

 File No. 333-288205

 Request for Effectiveness

 Dear Mr. Drory:

 Pursuant to Rule 461 of the General Rules and Regulations under the Securities Act of 1933, as amended, NRx Pharmaceuticals, Inc. respectfully requests that the effective date of the above-referenced Registration Statement on Form S-3/A (the “Registration Statement”) be accelerated so as to permit it to become effective at 5:00 p.m. Washington D.C. time on December 22, 2025, or as soon thereafter as practicable.

 Please call Kevin J. Roggow of Cozen O’Connor at (212) 908-1294 to provide notice of the effectiveness of the Registration Statement.

 * * *

 [ Signature Page Follows]

 Very truly yours,

 NRx Pharmaceuticals, Inc.

 By:

 /s/ Jonathan Javitt

 Name:

 Jonathan Javitt

 Title:

 Interim Chief Executive Officer

 cc:

 Kevin J. Roggow

 Cozen O ’ Connor

 [ Signature Page to Acceleration Request Letter ]

 2

June 24, 2025
Jonathan Javitt
Chairman and Interim Chief Executive Officer
NRX Pharmaceuticals, Inc.
1201 Orange Street, Suite 600
Wilmington, DE 19801
Re:NRX Pharmaceuticals, Inc.
Registration Statement on Form S-3
Filed June 20, 2025
File No. 333-288205
Dear Jonathan Javitt:
            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 Jason Drory at 202-551-8342 with any questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:Jack Kennedy

CORRESP
1
filename1.htm

NRx Pharmaceuticals, Inc.

1201 N. Market Street

Suite 111

Wilmington, Delaware
19801

June 16, 2022

VIA EDGAR

Division of Corporation Finance

Securities and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549

Attention: Mr. Daniel Crawford

NRX Pharmaceuticals, Inc.

Registration Statement on

Form S-3 (File No. 333-265492)

Dear Mr. Crawford:

Pursuant to Rule 461 of the Securities Act of 1933, as amended,
we hereby request that the effective date of the above-captioned Registration Statement on Form S-3 (the “S-3”)
of NRx Pharmaceuticals, Inc. (the “Company”) be accelerated to June 21, 2022 at 4:00 p.m. E.S.T.
or as soon thereafter as may be practicable.

We understand that the Staff will consider this request as confirmation
by the Company of its awareness of its responsibilities under the federal securities laws as they relate to the issuance of the securities
covered by the S-3. If you have any questions regarding the foregoing, please contact David Huntington of Paul Weiss Rifkin Wharton &
Garrison LLP at (212) 373-3124 or dhuntington@paulweiss.com.

Very truly yours,

    By:
    /s/ Alessandra Daigneault

    Name:
    Alessandra Daigneault

    Title:
    Chief Corporate Officer, General Counsel and Corporate Secretary

United States securities and exchange commission logo
June 13, 2022
Alessandra Daigneault, Esq.
Chief Corporate Officer, General Counsel & Secretary
NRX Pharmaceuticals, Inc.
1201 Orange Street, Suite 600
Wilmington, DE 19801
Re:NRX Pharmaceuticals, Inc.
Registration Statement on Form S-3
Filed June 9, 2022
File No. 333-265492
Dear Ms. Daigneault:
            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:       David Huntington, Esq.

CORRESP
1
filename1.htm

NRx Pharmaceuticals,
Inc.

1201 N. Market Street

Suite 111

Wilmington, Delaware
19801

April 18, 2022

VIA EDGAR

Division of Corporation Finance

Securities and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549

Attention: Ms. Abby Adams

NRX Pharmaceuticals, Inc.

Registration Statement on

Form S-1 (File No. 333-264201)

Dear Ms. Adams:

Pursuant to Rule 461 of the Securities Act of 1933, as amended, we
hereby request that the effective date of the above-captioned Registration Statement on Form S-1 (the “S-1”)
of NRx Pharmaceuticals, Inc. (the “Company”) be accelerated to April 19, 2022 at 4:00 p.m. E.S.T. or as soon
thereafter as may be practicable.

We understand that the Staff will consider this request as confirmation
by the Company of its awareness of its responsibilities under the federal securities laws as they relate to the issuance of the securities
covered by the S-1. If you have any questions regarding the foregoing, please contact Alex Lloyd of Kirkland & Ellis LLP at (617)
459-6765 or alex.lloyd@kirkland.com.

Very truly yours,

    By:
    /s/ Alessandra Daigneault

    Name:
    Alessandra Daigneault

    Title:
    Chief Corporate Officer, General Counsel and Corporate Secretary

United States securities and exchange commission logo
April 15, 2022
Alessandra Daigneault, Esq.
General Counsel and Secretary
NRX Pharmaceuticals, Inc.
1201 North Market Street, Suite 111
Wilmington, Delaware 19801
Re:NRX Pharmaceuticals, Inc.
Registration Statement on Form S-1
Filed April 8, 2022
File No. 333-264201
Dear Ms. Daigneault:
            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 Abby Adams at (202) 551-6902 with any questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:       Alexander Lloyd, Esq.

CORRESP
1
filename1.htm

NRX Pharmaceuticals, Inc.

1201 Orange Street, Suite 600

Wilmington, DE 19801

September 13, 2021

VIA EDGAR

Division of Corporation Finance

Securities and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549

Attention: Deanna Virginio

NRX Pharmaceuticals, Inc.

Registration Statement on

Form S-1 (File No. 333- 259336)

Dear Ms. Virginio:

Pursuant to Rule 461 of the Securities Act of
1933, as amended, we hereby request that the effective date of the above-captioned Registration Statement on Form S-1 (the “S-1”)
of NRX Pharmaceuticals, Inc. (the “Company”) be accelerated to September 15, 2021 at 4:00 p.m. E.S.T. or as
soon thereafter as may be practicable.

We understand that the Staff will consider this
request as confirmation by the Company of its awareness of its responsibilities under the federal securities laws as they relate to the
issuance of the securities covered by the Registration Statement. If you have any questions regarding the foregoing, please contact David
S. Huntington of Paul, Weiss, Rifkind, Wharton & Garrison LLP at (212) 373-3124.

*****

  Very truly yours,

  By:
  /s/ Alessandra Daigneault

  Name:
  Alessandra Daigneault

  Title:
  Chief Corporate Officer, General Counsel, Secretary and Acting Treasurer

CORRESP
1
filename1.htm

CORRESP

 NRX PHARMACEUTICALS, INC.

1201 Orange Street, Suite 600

Wilmington, DE 19801

July 7, 2021

 VIA EDGAR

Securities and Exchange Commission

 Division of Corporation
Finance

 100 F Street, N.E.

 Washington, D.C. 20549

Attention:
 Chris Edwards

Re:
 NRx Pharmaceuticals, Inc.

 Form S-1

 File No. 333-257438

Dear Mr. Edwards:

 In accordance with Rule
461 of the Securities Act of 1933, as amended, NRx Pharmaceuticals, Inc. (the “Company”) hereby respectfully requests that the effective date of its Registration Statement on Form S-1 (File No. 333-257438) (the “Registration Statement”), relating to the registration of up to an aggregate of 12,343,508 shares of common stock of the Company to be sold by certain selling
stockholders, be accelerated by the Securities and Exchange Commission to 4 p.m., New York City time, on July 9, 2021, or as soon thereafter as practicable.

It would be appreciated if, as soon as the Registration Statement is declared effective, you would so inform David S. Huntington at (212) 373-3124 and David A. Curtiss at (212) 373- 3146, with written confirmation sent to the address listed on the cover of the Registration Statement to follow.

Sincerely,

NRX PHARMACEUTICALS, INC.

By:

/s/ Alessandra Daigneault

Name: Alessandra Daigneault

Title:    General Counsel and Secretary

United States securities and exchange commission logo
July 2, 2021
Alessandra Daigneault
General Counsel and Secretary
NRX Pharmaceuticals, Inc.
1201 North Market Street, Suite 111
Wilmington, Delaware 19801
Re:NRX Pharmaceuticals, Inc.
Registration Statement on Form S-1
Filed June 25, 2021
File No. 333-257438
Dear Ms. Daigneault:
            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.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:       David A. Curtiss, Esq.

CORRESP
1
filename1.htm

CORRESP

 Big Rock Partners Acquisition Corp.

2645 N. Federal Highway, Suite 230

Delray Beach, FL 33483

 (310) 734-2300

 May 21, 2021

Division of Corporation Finance

 Office of Life Sciences

Securities and Exchange Commission

 Washington, D.C. 20549

Re:
 Big Rock Partners Acquisition Corp.

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

 Filed May 20, 2021

 File No. 333-252479

Ladies and Gentlemen:

 Big Rock Partners
Acquisition Corp. (“BRPA”) hereby responds as follows to the comment letter from the staff of the Securities and Exchange Commission (the “Staff”) dated May 20, 2021, relating to the above-referenced
Registration Statement on Form S-4 (the “Registration Statement”). For the Staff’s convenience, we have recited each of the comments in the Staff’s letter below in bold and italics,
and set forth the response in regular font immediately thereafter.

 Capitalized terms used but not defined herein have the meanings
ascribed to them in the Registration Statement.

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

 Cover Page

1.
 We refer to prior comment 1. Please revise the cover page to explain what steps you and the parties would
take in the event of a delisting prior to the meeting and/or closing of the merger. Explain how investors would be informed.

 We have revised the disclosures on the cover page, as requested.

Proposal No. 7 – The Adjournment Proposal, page 170

2.
 With reference to your disclosure on page F-36, we note that your
amended charter requires that you consummate a Business Combination by May 24, 2021. Accordingly, please revise Proposal No. 7 to limit the duration of the adjournment so that it does not extend beyond May 24, 2021 or advise.

 We have revised the disclosures on page 170 and elsewhere of the Registration Statement, as requested.

 General

3.
 We refer to prior comment 12. As stated during our telephone conversation with your counsel earlier
today, we have concerns with respect to the manner and timing by which you plan to disseminate the joint proxy/prospectus in relation to the BRPA shareholder meeting and closing of the merger, which are both scheduled for Monday, May 24, 2021.
Accordingly, we make no representation as to the sufficiency of the time that you plan to provide the BRPA shareholders: (i) to make an informed voting decision on the proposals; and (ii) to make an informed investment decision with
respect to conversion of their shares. In addition, we make no representation as to whether the manner or timing of the delivery to the NeuroRx holders satisfies the delivery requirements under the Securities Act.

 The Staff’s position is duly noted.

*************

 If you have any
questions, please do not hesitate to contact me at the above telephone number.

Sincerely,

/s/ Richard Ackerman

Richard Ackerman, Chairman, President and Chief Executive Officer

United States securities and exchange commission logo
May 20, 2021
Richard Ackerman
Chief Executive Officer
Big Rock Partners Acquisition Corp.
2645 N. Federal Highway, Suite 230
Delray Beach, FL 33483
Re:Big Rock Partners Acquisition Corp.
Amendment No. 4 to Registration Statement on Form S-4
Filed May 20, 2021
File No. 333-252479
Dear Mr. Ackerman:
            We have reviewed your amended registration statement 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 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.  Unless we note
otherwise, our references to prior comments are to comments in our May 19, 2021 letter.
Amendment No. 4 to Registration Statement on Form S-4
Cover page
1.We refer to prior comment 1.  Please revise the cover page to explain what steps you and
the parties would take in the event of a delisting prior to the meeting and/or closing of the
merger.  Explain how investors would be informed.
Proposal No. 7 - The Adjournment Proposal, page 170
2.With reference to your disclosure on page F-36, we note that your amended charter
requires that you consummate a Business Combination by May 24, 2021.  Accordingly,
please revise Proposal No. 7 to limit the duration of the adjournment so that it does not
extend beyond May 24, 2021 or advise.

 FirstName LastNameRichard Ackerman
 Comapany NameBig Rock Partners Acquisition Corp.
 May 20, 2021 Page 2
 FirstName LastName
Richard Ackerman
Big Rock Partners Acquisition Corp.
May 20, 2021
Page 2
General
3.We refer to prior comment 12.  As stated during our telephone conversation with your
counsel earlier today, we have concerns with respect to the manner and timing by which
you plan to disseminate the joint proxy/prospectus in relation to the BRPA shareholder
meeting and closing of the merger, which are both scheduled for Monday, May 24, 2021.
Accordingly, we make no representation as to the sufficiency of the time that you plan to
provide the BRPA shareholders: (i) to make an informed voting decision on the proposals;
and (ii) to make an informed investment decision with respect to conversion of their
shares.  In addition, we make no representation as to whether the manner or timing of the
delivery to the NeuroRx holders satisfies the delivery requirements under the Securities
Act.
            You may contact Tracie Mariner at (202) 551-3744 or Al Pavot at (202) 551-3738 if you
have questions regarding comments on the financial statements and related matters. Please
contact Alan Campbell at (202) 551-4224 or Joe McCann at (202) 551-6262 with any other
questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:       Jeffrey M. Gallant, Esq.

CORRESP
1
filename1.htm

CORRESP

 Big Rock Partners Acquisition Corp.

2645 N. Federal Highway, Suite 230

Delray Beach, FL 33483

 (310) 734-2300

 May 21, 2021

Division of Corporation Finance

 Office of Life Sciences

Securities and Exchange Commission

 100 F Street, N.E.

Washington, D.C. 20549

Re:
 Big Rock Partners Acquisition Corp.

 Registration Statement on Form S-4

 File No. 333-252479

Ladies and Gentlemen:

 Pursuant to Rule 461
promulgated under the Securities Act of 1933, as amended, Big Rock Partners Acquisition Corp. hereby requests that the effectiveness of the above-referenced Registration Statement be accelerated so that such Registration Statement will become
effective at 2:00 p.m., Eastern Time, on May 21, 2021, or as soon thereafter as practicable.

 Sincerely,

/s/ Richard Ackerman

 Richard Ackerman, Chief Executive Officer

CORRESP
1
filename1.htm

CORRESP

 Big Rock Partners Acquisition Corp.

2645 N. Federal Highway, Suite 230

Delray Beach, FL 33483

 (310) 734-2300

 May 20, 2021

Division of Corporation Finance

 Office of Life Sciences

Securities and Exchange Commission

 Washington, D.C. 20549

Re:
 Big Rock Partners Acquisition Corp.

 Amendment No. 3 to Registration Statement on Form S-4

 Filed May 19, 2021

 File No. 333-252479

Ladies and Gentlemen:

 Big Rock Partners
Acquisition Corp. (“BRPA”) hereby responds as follows to the comment letter from the staff of the Securities and Exchange Commission (the “Staff”) dated May 19, 2021, relating to the above-referenced
Registration Statement on Form S-4 (the “Registration Statement”). For the Staff’s convenience, we have recited each of the comments in the Staff’s letter below in bold and
italics, and set forth the response in regular font immediately thereafter.

 Capitalized terms used but not defined herein have the
meanings ascribed to them in the Registration Statement.

 Amendment No. 3 to Registration Statement on Form
S-4

 Cover Page

1.
 We note your response to prior comment 2 and revised disclosure indicating that the Nasdaq listing
condition can be waived. Please revise to update this disclosure to indicate whether each party has made a determination as to whether to waive or not waive the condition. To the extent that any party has not made a determination concerning waiver,
please (i) revise to clarify when such waiver decision would be made and (ii) note that we may have additional comment.

We respectfully advise the Staff that, at this time, the parties have not made a determination as to whether to waive or not waive the Nasdaq
listing condition. Such decision would be expected to be made promptly following any delisting from Nasdaq . We have revised the disclosures on the cover page, as requested, and elsewhere as appropriate and duly note that the Staff may issue an
additional comment.

2.
 We note the second paragraph highlights Fast Track designation for
RLF-100 as well as a commercial partnership and global commercialization. Accordingly, please revise this paragraph to clarify that the product candidate has not been approved by FDA.

 We have revised the disclosures on the cover page, as requested.

 Summary of the Proxy Statement / Prospectus / Consent Solicitation Statement, page 22

3.
 We refer to prior comment 16 and re-issue in part. Please revise
the Prospectus Summary to clarify whether FDA denied or refused to grant NeuroRx’s September 2020 application for emergency use authorization for ZYESAMI.

We have revised the disclosures on page 25 of the Registration Statement, as requested.

Risk Factors, page 44

4.
 With reference to your disclosure on page 198, please revise to add a risk factor to highlight that FDA
has not explained how it will determine whether efficacy has been demonstrated in the context of an Emergency Use Authorization request relating to COVID-19 with Respiratory Failure (COVID-AIV).

 We have revised the disclosures on page 48 of the Registration
Statement, as requested.

 Our product candidates are in Phase IIb/III of clinical testing.., page 47

5.
 We note your response to prior comment 4. Your revised disclosures on pages 47-48 indicate that the Phase IIb/III trial was “successful” and that achievement of the stated primary endpoint in the second trial would qualify as a second Phase III trial in support of an NDA for
ZYESAMI. Please tell us the basis for these statements. Also, please revise to clarify that safety and efficacy determinations are within FDA’s purview and that trial results do not guarantee regulatory approval.

We have revised the disclosures on page 48 of the Registration Statement, as requested.

6.
 Your revised disclosure in this section states that ZYESAMI will be evaluated in a second Phase III
clinical trial in which the primary endpoint is increased likelihood of recover from respiratory failure at 90 days compared to placebo. However, your disclosure in the preceding sentence and on page 192 indicates that ZYESAMI will be compared to
remdesivir. Please reconcile your disclosure or advise.

 We have revised the disclosures on page 48 of the
Registration Statement, as requested.

 We do not anticipate maintaining orphan drug protection for the treatment of COVID-19.., page 51

7.
 We note your revised disclosures on pages 52 and 230 in response to prior comment 5; however, your risk
factor header on page 51 continues to imply that NeuroRx currently has orphan drug protection for the treatment of COVID-19. Accordingly please revise the header or advise.

We have revised the risk factor header on page 52 of the Registration Statement, as requested.

We must enter into agreements with, and depend upon, one or more partners…, page 72

8.
 We note your response to prior comment 6 and re-issue. Your
disclosure remains unclear as to whether NeuroRx’s plan is for the collaboration agreement with Relief Therapeutics to provide the funding necessary to commercialize ZYESAMI in the markets covered under the agreement. Please revise or advise.

 We have revised the disclosures on pages 73 of the Registration Statement, as requested.

 Business of NeuroRx, page 187

9.
 We note your response to prior comment 12 and revised disclosure. We further note your statement that the
Phase IIb/III trial of ZYESAMI (the “Intravenous Trial”) met its primary specified endpoint “when adjusting for ventilation status and treatment site.” However, your disclosure on pages 191 and
198-199 indicates that the Intravenous Trial did not achieve statistical significance before controlling for ventilation status and treatment site. Please revise your disclosure on page 187 and throughout the
Business of NeuroRx section to clearly state whether or not the Intravenous Trial met its primary prespecified endpoint before making any adjustments to trial data.

We have revised the disclosures on pages 188 and elsewhere of the Registration Statement, as requested.

10.
 Please revise to ensure consistent disclosure in the proxy/prospectus concerning the Intravenous Trial,
including: (i) the endpoint of this trial, (ii) whether or not ZYESAMI met the primary endpoint, before any adjustments, and (iii) the associated p-value(s). For instance, your disclosure on
page 192 indicates that “ZYESAMI met the primary endpoint for successful recovery from respiratory failure at days 28 (P=.014) and 60 (P=0.13); however, your disclosure in the fourth paragraph on page 198 states that at 28 days the P value was
at .08, a difference that does not meet the conventional P<.05 threshold for statistical significance.

 We
have revised the disclosures on page 193 of the Registration Statement, as requested.

11.
 We note your response to prior comment 13 and re-issue in part.
While your revised disclosure discusses the intellectual property coverage of NRX-101, there is no discussion of the intellectual property coverage of ZYESAMI. Please revise the Business of NeuroRx section,
where appropriate, to disclose the scope of the patent protection, or other IP coverage, for ZYESAMI. To the extent that NeuroRx does not own or license any patents that relate to ZYESAMI, please add risk factor disclosure or advise.

 We have revised the disclosures on pages 68 and 69 of the Registration Statement to add the requested risk
factor.

 General

12.
 Your proxy/prospectus indicates that BRPA will hold its annual meeting on May 24, 2021 at 8:30 a.m.,
eastern time and that BRPA shareholders must demand conversion of their shares to cash and deliver the shares to BRPA’s transfer agent physically or electronically “no later than two business days prior to the vote at the meeting.”
With reference to Rule 14a-9, please explain how your processes ensure that BRPA shareholders will have sufficient time to make: (i) an informed voting decision regarding the Business Combination Proposal
and other meeting proposals and (ii) an informed investment decision with respect to their conversion rights. In addition, we refer you to the guidance set forth in Release No. 34-33768 (March 16,
1994) which reminds registrants that proxy materials “must be mailed sufficiently in advance of the meeting date to allow five business days for processing by the banks and brokers and an additional period to provide ample time for delivery of
the material, consideration of the material by the beneficial owners, return of their voting instructions, and transmittal of the vote from the bank or broker to the tabulator.”

The Staff’s comment is duly noted. We have considered the guidance set forth in Release
No. 34-33768 and note that the purpose of Rule 14a-13 and the guidance set forth in Release No. 34-33768 was to ensure
that stockholders receive proxy soliciting material with sufficient time to make an informed voting decision. We respectfully advise the Staff that BRPA mailed a notice of the annual meeting to its stockholders on May 14, 2021, which informed
stockholders of the date and time of the annual meeting and the proposals to be considered thereat, included a summary of the principal terms of the business combination and related matters, and directed stockholders to review the definitive proxy
statement/consent solicitation statement/prospectus once available. The notice is also available online on BRPA’s proxy hosting website and through EDGAR. Accordingly, stockholders will have had at least 10 days to consider the proposals and
make their voting and investment decision before the date of the annual meeting. Additionally, once the Registration Statement is declared effective, BRPA intends to

issue a press release and file a Current Report on Form 8-K to ensure that stockholders are aware that definitive documentation is available for review
online on BRPA’s proxy hosting website and through EDGAR. The Staff has previously noted that electronic sources of information, including EDGAR and other internet sources, are increasingly relied upon by the investment community for
information regarding public companies (see, for instance, Release No. 33-7760 (January 24, 2000) and Release No. 33-8591 (July 19, 2005)), and we believe that
by mailing and posting the notice of meeting and filing the Form 8-K and issuing the press release, we are following the policy considerations the Staff expressed in Release
No. 34-33768 and therefore would appropriately be providing investors with the substantive information as to allow them to make an informed voting and investment decision through means that maximize their
access to the information.

 Further, we respectfully advise the Staff that the voting decisions of unaffiliated stockholders will not
change the outcome of the stockholder vote on any of the proposals to be considered by the stockholders. The officers, directors and affiliates of BRPA, who hold an aggregate of 2,067,500 shares of Common Stock, which currently constitutes
approximately 76.9% of the outstanding shares of Common Stock, have agreed to vote in favor of the business combination proposal and intend to vote such shares in favor of the other proposals. Accordingly, each of the proposals being submitted to
BRPA stockholders can be approved even if every holder of Public Shares votes against such proposals or does not vote at all. The foregoing is indicated in the risk factor titled “The business combination may be completed even if every
public stockholder votes against the business combination proposal.” that is included in the Registration Statement. As a result, the need for the unaffiliated holders to make an informed voting decision is not paramount in the present
transaction.

 With respect to the exercise of conversion rights by the holders of Public Shares, we have revised the disclosures
throughout the Registration Statement to provide that the holders of Public Shares will have two weeks following the consummation of the Business Combination to exercise their conversion rights. Accordingly, public holders will have adequate time to
make an informed investment decision as directed by the aforementioned release. We therefore believe that the rationale and safeguards meant to be afforded to public holders required by the guidance set forth in Release No. 34-33768 are fairly and adequately addressed in the current situation.

 *************

If you have any questions, please do not hesitate to contact me at the above telephone number.

 Sincerely,

/s/ Richard Ackerman

Richard Ackerman, Chairman, President and Chief Executive Officer

United States securities and exchange commission logo
May 19, 2021
Richard Ackerman
Chief Executive Officer
Big Rock Partners Acquisition Corp.
2645 N. Federal Highway, Suite 230
Delray Beach, FL 33483
Re:Big Rock Partners Acquisition Corp.
Amendment No. 3 to Registration Statement on Form S-4
Filed May 19, 2021
File No. 333-252479
Dear Mr. Ackerman:
            We have reviewed your amended registration statement 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 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.  Unless we note
otherwise, our references to prior comments are to comments in our May 5, 2021 letter.
Amendment No. 3 to Registration Statement on Form S-4
Cover Page
1.We note your response to prior comment 2 and revised disclosure indicating that the
Nasdaq listing condition can be waived. Please revise to update this disclosure to indicate
whether each party has made a determination as to whether to waive or not waive the
condition.  To the extent that any party has not made a determination concerning waiver,
please (i) revise to clarify when such waiver decision would be made and (ii) note that we
may have additional comment.
2.We note that the second paragraph highlights Fast Track designation for RLF-100 as well
as a commercial partnership and global commercialization.  Accordingly, please revise
this paragraph to clarify that the product candidate has not been approved by FDA.

 FirstName LastNameRichard Ackerman
 Comapany NameBig Rock Partners Acquisition Corp.
 May 19, 2021 Page 2
 FirstName LastNameRichard Ackerman
Big Rock Partners Acquisition Corp.
May 19, 2021
Page 2
Summary of the Proxy Statement / Prospectus / Consent Solicitation Statement, page 22
3.We refer to prior comment 16 and re-issue in part. Please revise the Prospectus Summary
to clarify whether FDA denied or refused to grant NeuroRx's September 2020 application
for emergency use authorization for ZYESAMI.
Risk Factors, page 44
4.With reference to your disclosure on page 198, please revise to add a risk factor to
highlight that FDA has not explained how it will determine whether efficacy has been
demonstrated in the context of an Emergency Use Authorization request relating to
COVID-19 with Respiratory Failure (COVID-AIV).
Our product candidates are in Phase IIb/III of clinical testing., page 47
5.We note your response to prior comment 4. Your revised disclosures on pages 47-
48 indicate that the Phase IIb/III trial was "successful" and that achievement of the
stated primary endpoint in the second trial would qualify as a second Phase III trial in
support of an NDA for ZYESAMI.  Please tell us the basis for these statements.  Also,
revise to clarify that safety and efficacy determinations are within FDA's purview and that
trial results do not guarantee regulatory approval.
6.Your revised disclosure in this section states that ZYESAMI will be evaluated in a second
Phase III clinical trial in which the primary endpoint is increased likelihood of recovery
from respiratory failure at 90 days compared to placebo. However, your disclosure in the
preceding sentence and on page 192 indicates that ZYESAMI will be compared to
remdesivir. Please reconcile your disclosure or advise.
We do not anticipate maintaining orphan drug protection for the treatment of COVID-19., page
51
7.We note your revised disclosures on pages 52 and 230 in response to prior comment 5;
however, your risk factor header on page 51 continues to imply that NeuroRx currently
has orphan drug protection for the treatment of COVID-19. Accordingly please revise the
header or advise.
We must enter into agreements with, and depend upon, one or more partners..., page 72
8.We note your response to prior comment 6 and re-issue. Your disclosure remains unclear
as to whether NeuroRx's plan is for the collaboration agreement with Relief Therapeutics
to provide the funding necessary to commercialize ZYESAMI in the markets covered
under the agreement. Please revise or advise.
Business of NeuroRx, page 187
9.We note your response to prior comment 12 and revised disclosure. We further note your
statement that the Phase IIB/III trial of ZYESAMI (the “Intravenous Trial”) met its

 FirstName LastNameRichard Ackerman
 Comapany NameBig Rock Partners Acquisition Corp.
 May 19, 2021 Page 3
 FirstName LastName
Richard Ackerman
Big Rock Partners Acquisition Corp.
May 19, 2021
Page 3
primary prespecified endpoint "when adjusting for ventilation status and treatment site."
However, your disclosure on pages 191 and 198-199 indicates that the Intravenous Trial
did not achieve statistical significance before controlling for ventilation status and
treatment site.  Please revise your disclosure on page 187 and throughout the Business of
NeuroRx section to clearly state whether or not the Intravenous Trial met its primary
prespecified endpoint before making any adjustments to trial data.
10.Please revise to ensure consistent disclosure in the proxy/prospectus concerning
the Intravenous Trial, including: (i) the endpoint of this trial, (ii) whether or not
ZYESAMI met the primary endpoint, before any adjustments, and (iii) the associated p-
values(s).  For instance, your disclosure on page 192 indicates that "ZYESAMI met the
primary endpoint for successful recovery from respiratory failure at days 28 (P = .014)
and 60 (P = .013); however, your disclosure in the fourth paragraph on page 198 states
that at 28 days the P value was at .08, a difference that does not meet the conventional
P<.05 threshold for statistical significance.
11.We note your response to prior comment 13 and re-issue in part. While your revised
disclosure discusses the intellectual property coverage of NRX-101, there is no discussion
of the  intellectual property coverage of ZYESAMI. Please revise the Business of
NeuroRx section, where appropriate, to disclose the scope of the patent protection, or
other IP coverage, for ZYESAMI. To the extent that NeuroRx does not own or license any
patents that relate to ZYESAMI, please add risk factor disclosure or advise.
General
12.Your proxy/prospectus indicates that BRPA will hold its annual meeting on May 24, 2021
at 8:30 a.m., eastern time and that BRPA shareholders must demand conversion of their
shares to cash and deliver the shares to BRPA’s transfer agent physically or
electronically “no later than two business days prior to the vote at the meeting.”  With
reference to Rule 14a-9, please explain how your processes ensure that BRPA
shareholders will have sufficient time to make: (i) an informed voting decision regarding
the Business Combination Proposal and other meeting proposals and (ii) an informed
investment decision with respect to their conversion rights.  In addition, we refer you to
the guidance set forth in Release No. 34-33768 (March 16, 1994) which reminds
registrants that proxy materials "must be mailed sufficiently in advance of the meeting
date to allow five business days for processing by the banks and brokers and an additional
period to provide ample time for delivery of the material, consideration of the material by
the beneficial owners, return of their voting instructions, and transmittal of the vote from
the bank or broker to the tabulator."

 FirstName LastNameRichard Ackerman
 Comapany NameBig Rock Partners Acquisition Corp.
 May 19, 2021 Page 4
 FirstName LastName
Richard Ackerman
Big Rock Partners Acquisition Corp.
May 19, 2021
Page 4
            You may contact Tracie Mariner at (202) 551-3744 or Al Pavot at (202) 551-3738 if you
have questions regarding comments on the financial statements and related matters. Please
contact Alan Campbell at (202) 551-4224 or Joe McCann at (202) 551-6262 with any other
questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:       Jeffrey M. Gallant, Esq.

CORRESP
1
filename1.htm

CORRESP

 Big Rock Partners Acquisition Corp.

2645 N. Federal Highway, Suite 230

Delray Beach, FL 33483

 (310) 734-2300

 May 11, 2021

Division of Corporation Finance

 Office of Life Sciences

Securities and Exchange Commission

 Washington, D.C. 20549

Re:

 Big Rock Partners Acquisition Corp.

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

Filed April 16, 2021

 File No. 333-252479

 Ladies and Gentlemen:

Big Rock Partners Acquisition Corp. (“BRPA”) hereby responds as follows to the comment letter from the staff of the Securities
and Exchange Commission (the “Staff”) dated May 5, 2021, relating to the above-referenced Registration Statement on Form S-4 (the “Registration Statement”). For the
Staff’s convenience, we have recited each of the comments in the Staff’s letter below in bold and italics, and set forth the response in regular font immediately thereafter.

Capitalized terms used but not defined herein have the meanings ascribed to them in the Registration Statement.

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

Cover Page

1.
 Please revise your disclosure here and elsewhere in the prospectus to clarify what percentage of the
shares in the combined company will be owned by the Sponsor and what percentage of shares in the combined company will be owned by BRPA’s public stockholders.

We have revised the disclosures on the cover page and pages 4, 25, 107 and 290 of the Registration Statement, as requested.

2.
 We note your revised cover page disclosure in response to prior comment 5. Given that the listing
condition is waivable, please revise the cover page to prominently disclose that shareholders will not have certainty at the time they vote regarding whether the Common Stock and Warrants will be listed on a national securities exchange following
the business combination. Also, reference the risk factor disclosure on page 72.

 We have revised the
disclosures on the cover page, as requested.

 Summary of the Proxy Statement / Prospectus / Consent Solicitation Statement, page 22

3.
 With reference to your disclosure on page 46, please update the Summary section to discuss NeuroRx’s
dispute with Relief Therapeutics Holding AG. Also, revise the second paragraph of the cover page to provide a cross reference to the “Division of Profits” disclosure on page 211.

We have revised the disclosures on the cover page and page 221 of the Registration Statement, as requested.

Risk Factors

 Our product
candidates are in Phase IIb/III of clinical testing, page 45

4.
 Please reconcile this risk factor with your disclosures on page 180 and elsewhere. In this regard, it
should be clear in the risk factor which drug or drug candidates you are referencing and whether the trials are completed or remain open. Also, we note your disclosure that you will need to commit substantial time and additional resources to
conducting further nonclinical studies and clinical trials before you can submit an NDA. Accordingly, revise, if appropriate, to discuss the funding and the trials needed to commercialize NRX-101, or revise to
clarify the risk factor disclosure.

 We have revised the disclosures on pages 46 and 188 of the Registration
Statement, as requested.

 We do not anticipate maintaining orphan drug protection for the treatment of
COVID-19..., page 49

5.
 Please revise to disclose the dates that the parties received and/or transferred the orphan drug
designations covering RLF-100 and NRX-101.

We have revised the disclosures on pages 51 and 227 of the Registration Statement, as requested.

We must enter into agreements with, and depend upon, one or more partners..., page 69

6.
 We note your response to prior comment 7 and updated disclosure and
re-issue. In this regard, it remains unclear whether your plan is for the collaboration agreement with Relief Therapeutics to provide the funding necessary to commercialize ZYESAMI in the markets covered under
the agreement.

 We have revised the disclosures on pages 25, 47, 48, 71, 220 and 221 of the Registration
Statement, as requested.

 Proposal No. 1 — The Business Combination Proposal

Merger Consideration, page 103

7.
 We note your response to prior comment 8 and revised disclosure. Please revise to clarify whether the
terms of the Earnout Cash Milestone (i) require the cash to be delivered to NeuroRx stockholders within a specified period of time and (ii) allow for any contingency or delay in payment if NRX Pharmaceuticals does not have sufficient
capital and is unable to raise sufficient capital in order to pay the Earnout Cash, particularly if NRX Pharmaceuticals is still in the process of beginning to commercialize ZYESAMI when the Earnout Cash becomes due.May

 We have revised the disclosures on the cover page and pages 106 and 123 of the Registration Statement, as
requested.

 Big Rock’s Board of Directors’ Reasons for Approval of the Merger Agreement, page 112

8.
 We refer to prior comment 10 and note the disclosure that EBC presented a comparable companies analysis
to the Board. Please explain whether this analysis served as a basis for the Board’s valuation of the company or either of the two lead drug candidates. If it did, then please revise to clarify this point and present the comparable companies
analysis in the prospectus. If it did not serve as a basis, then revise to explain how the Board came to that conclusion concerning the comparable companies analysis.

We have revised the disclosures on pages 115 and 116 of the Registration Statement, as requested.

9.
 Please revise to explain whether the Board’s valuation of NeuroRx was predicated on any material
assumptions regarding the timing of regulatory approval and/or authorization for either of the two lead product candidates. Also revise to indicate whether NeuroRx provided the Board with financial projections. To the extent that projections were
provided, please indicate when the projections were provided and whether the Board used such projections to value NeuroRx.

We have revised the disclosures on page 116 of the Registration Statement, as requested.

BRPA’s Management’s Discussion and Analysis of Financial Condition and Results of Operations

Liquidity and Capital Resources, page 174

10.
 We note your response to prior comment 12 and revised disclosure. We further note your disclosure on page
F-8 indicates that BRAC is affiliated with the “underwriter.” Please revise throughout to clarify, if true, that BRAC Lending Group is affiliated with Early Bird Capital, the underwriter of
BRPA’s initial public offering, and discuss any associated conflicts of interest.

 We have revised the
disclosures on pages 1, 183, and 266 of the Registration Statement and have discussed conflicts of interest on page 30 and 31 and 118 and 119 of the Registration Statement, as requested.

Beneficial Ownership of Securities of BRPA and NRX Pharmaceuticals, page 176

11.
 Please revise to identify the natural persons with voting and/or dispositive control of the shares held
by GEM Yield Bahamas Limited in footnote 10 to the beneficial ownership table.

 We have revised the disclosures
on page 183 of the Registration Statement, as requested.

 Business of NeuroRx, page 179

12.
 We note your statements that ZYESAMI has “demonstrated clear benefit in both survival and recovery
from respiratory failure” and that it is the first COVID-19 therapeutic to “demonstrate advantages in both survival and recovery from critical COVID-19.”
Please revise to avoid stating that ZYESAMI has demonstrated “clear benefit” or “advantages” as this may create an inference that your product is likely to be declared safe and effective, which is a determination solely in the
authority of regulatory agencies such as the FDA. You may present clinical trial end points and objective data resulting from trials without concluding efficacy. In your revisions, please also clarify that the results from your clinical trials of
ZYESAMI do not provide a guarantee that ZYESAMI will be deemed to be safe or effective for the treatment of COVID-19, and that extensive clinical testing and regulatory approval will be required before ZYESAMI
can be commonly prescribed for the treatment of COVID-19.

 We have revised the disclosures on pages 184, 189, 195 and 197 of the Registration
Statement, as requested.

13.
 We note your response to prior comment 18 and re-issue. Please
revise the Business of NeuroRx section, where appropriate, to disclose the nature of NeuroRx’s material intellectual property including the scope of the patent protection for NeuroRx’s product candidates and whether such patents are owned
or licensed as well as the duration of any patents, trademarks, licenses, franchises and concessions held by NeuroRx.

We have revised the disclosures on pages 185 and 186 of the Registration Statement, as requested.

ZYESAMI Phase IIb/III Clinical Trial for treatment of Respiratory Failure in Critical COVID- 19, page 180

14.
 We note your statement on page 181 that ZYESAMI demonstrated a meaningful benefit in survival after
controlling for ventilation status and treatment site. Please revise to clearly explain the meaning of the term “meaningful benefit” and whether the results were statistically significant. Also explain why and how NeuroRx “controlled
for ventilation status and treatment site”. Present the results before controlling for ventilation status and treatment site.

We have revised the disclosures on page 184 of the Registration Statement, as requested.

Initial Human Studies of ZYESAMI in COVID-19 with Respiratory Failure, page 186

15.
 Please revise your disclosure in this section to provide a brief overview of statistical significance and
how the FDA assesses whether trial data demonstrates statistical significance.

 We have revised the disclosures
on page 195 of the Registration Statement, as requested.

16.
 We refer to a December 30, 2020 joint press release with Relief Therapeutics and a February 23,
2021 article by Endpoints News (as updated on February 26, 2021) which both indicate that in December 2020 FDA denied your September 2020 emergency use authorization application. Please advise or revise the prospectus summary, as well as other
appropriate sections of the prospectus, to discuss this regulatory determination, including the stated basis, if any, for FDA’s decision. Also revise the Business section to present the 28-day data and
discuss any and all changes to endpoints used during the course of the clinical trial.

 We have revised the
disclosures on page 195 of the Registration Statement, as requested.

 Critical COVID-19 with Respiratory
Failure, page 192

17.
 We note your response to prior comment 23 and re-issue. Please
revise your description of the trial under this heading, as well as the trial under the heading “Critical COVID-19 with Severe Comorbidity Expanded Access”, to disclose who is conducting the trial,
the phase of the trial, the primary and secondary endpoints, metrics utilized, the number and nature of any drug-related adverse events and the planned duration of the trial. To the extent any of these trials has been completed, please disclose
whether the trial achieved its primary and secondary endpoints. If the disclosure in these sections is duplicative of disclosure that appears elsewhere in the document, please consider removing this disclosure or including a cross-reference.

 We have revised the disclosures on page 201 of the Registration Statement, as requested.

 General

18.
 Please ensure that the opinions and consents of both Marcum and KPMG are included in your next amendment
in order for the Staff to timely process it.

 The opinions and consents of both Marcum and KPMG have been included in this
filing of the Registration Statement as requested.

 *************

If you have any questions, please do not hesitate to contact me at the above telephone number.

Sincerely,

 /s/ Richard Ackerman

Richard Ackerman, Chairman, President and Chief Executive Officer

cc:
 Graubard Miller

David Alan Miller, Esq.

 Jeffrey
M. Gallant, Esq.

 NeuroRx, Inc.

 Jonathan C.
Javitt, MD, MPH

 Alessandra Daigneault, Esq.

Paul, Weiss, Rifkind, Wharton & Garrison LLP

David S. Huntington, Esq.

 David
A. Curtiss, Esq.

United States securities and exchange commission logo
May 5, 2021
Richard Ackerman
Chief Executive Officer
Big Rock Partners Acquisition Corp.
2645 N. Federal Highway, Suite 230
Delray Beach, FL 33483
Re:Big Rock Partners Acquisition Corp.
Amendment No. 1 to Registration Statement on Form S-4
Filed April 16, 2021
File No. 333-252479
Dear Mr. Ackerman:
            We have reviewed your amended registration statement 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 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.  Unless we note
otherwise, our references to prior comments are to comments in our February 26, 2021 letter.
Amendment No. 1 to Registration Statement on Form S-4
Cover Page
1.Please revise your disclosure here and elsewhere in the prospectus to clarify what
percentage of the shares in the combined company will be owned by the Sponsor and what
percentage of shares in the combined company will be owned by BRPA's public
stockholders.
2.We note your revised cover page disclosure in response to prior comment 5.  Given that
the listing condition is waivable, please revise the cover page to prominently disclose that
shareholders will not have certainty at the time they vote regarding whether the Common
Stock and Warrants will be listed on a national securities exchange following the business
combination. Also, reference the risk factor disclosure on page 72.

 FirstName LastNameRichard Ackerman
 Comapany NameBig Rock Partners Acquisition Corp.
 May 5, 2021 Page 2
 FirstName LastName
Richard Ackerman
Big Rock Partners Acquisition Corp.
May 5, 2021
Page 2

Summary of the Proxy Statement / Prospectus / Consent Solicitation Statement, page 22
3.With reference to your disclosure on page 46, please update the Summary section to
discuss NeuroRx's dispute with Relief Therapeutics Holding AG.  Also, revise the second
paragraph of the coverpage to provide a cross reference to the "Division of Profits"
disclosure on page 211.
Risk Factors
Our product candidates are in Phase IIb/III of clinical testing, page 45
4.Please reconcile this risk factor with your disclosures on page 180 and elsewhere.  In this
regard, it should be clear in the risk factor which drug or drug candidates you are
referencing and whether the trials are completed or remain open.  Also, we note your
disclosure that you will need to commit substantial time and additional resources to
conducting further nonclinical studies and clinical trials before you can submit an NDA.
Accordingly, revise, if appropriate, to discuss the funding and the trials needed to
commercialize NRX-101, or revise to clarify the risk factor disclosure.

We do not anticipate maintaining orphan drug protection for the treatment of COVID-19..., page
49
5.Please revise to disclose the dates that the parties received and/or transferred the orphan
drug designations covering RLF-100 and NRX-101.
We must enter into agreements with, and depend upon, one or more partners..., page 69
6.We note your response to prior comment 7 and updated disclosure and re-issue. In this
regard, it remains unclear whether your plan is for the collaboration agreement with Relief
Therapeutics to provide the funding necessary to commercialize ZYESAMI in the markets
covered under the agreement.
Proposal No. 1 -- The Business Combination Proposal
Merger Consideration, page 103
7.We note your response to prior comment 8 and revised disclosure. Please revise to clarify
whether the terms of the Earnout Cash Milestone (i) require the cash to be delivered to
NeuroRx stockholders within a specified period of time and (ii) allow for any contingency
or delay in payment if NRX Pharmaceuticals does not have sufficient capital and is unable
to raise sufficient capital in order to pay the Earnout Cash, particularly if NRX
Pharmaceuticals is still in the process of beginning to commercialize ZYESAMI when the
Earnout Cash becomes due.

 FirstName LastNameRichard Ackerman
 Comapany NameBig Rock Partners Acquisition Corp.
 May 5, 2021 Page 3
 FirstName LastName
Richard Ackerman
Big Rock Partners Acquisition Corp.
May 5, 2021
Page 3
Big Rock's Board of Directors' Reasons for Approval of the Merger Agreement, page 112
8.We refer to prior comment 10 and note the disclosure that EBC presented a comparable
companies analysis to the Board.  Please explain whether this analysis served as a basis
for the Board's valuation of the company or either of the two lead drug candidates.  If it
did, then please revise to clarify this point and present the comparable companies analysis
in the prospectus.  If it did not serve as a basis, then revise to explain how the Board came
to that conclusion concerning the comparable companies analysis.
9.Please revise to explain whether the Board's valuation of NeuroRx was predicated on any
material assumptions regarding the timing of regulatory approval and/or authorization for
either of the two lead product candidates.  Also revise to indicate whether NeuroRx
provided the Board with financial projections.  To the extent that projections were
provided, please indicate when the projections were provided and whether the Board used
such projections to value NeuroRx.
BRPA's Management's Discussion and Analysis of Financial Condition and Results of
Operations
Liquidity and Capital Resources, page 174
10.We note your response to prior comment 12 and revised disclosure. We further note your
disclosure on page F-8 indicates that BRAC is affiliated with the "underwriter." Please
revise throughout to clarify, if true, that BRAC Lending Group is affiliated with Early
Bird Capital, the underwriter of BRPA's initial public offering, and discuss any associated
conflicts of interest.
Beneficial Ownership of Securities of BRPA and NRX Pharmaceuticals, page 176
11.Please revise to identify the natural persons with voting and/or dispositive control of the
shares held by GEM Yield Bahamas Limited in footnote 10 to the beneficial ownership
table.
Business of NeuroRx, page 179
12.We note your statements that ZYESAMI has "demonstrated clear benefit in both survival
and recovery from respiratory failure" and that it is the first COVID-19 therapeutic to
"demonstrate advantages in both survival and recovery from critical COVID-19." Please
revise to avoid stating that ZYESAMI has demonstrated "clear benefit" or "advantages" as
this may create an inference that your product is likely to be declared safe and effective,
which is a determination solely in the authority of regulatory agencies such as the
FDA. You may present clinical trial end points and objective data resulting from trials
without concluding efficacy. In your revisions, please also clarify that the results from
your clinical trials of ZYESAMI do not provide a guarantee that ZYESAMI will be
deemed to be safe or effective for the treatment of COVID-19, and that extensive clinical
testing and regulatory approval will be required before ZYESAMI can be commonly

 FirstName LastNameRichard Ackerman
 Comapany NameBig Rock Partners Acquisition Corp.
 May 5, 2021 Page 4
 FirstName LastName
Richard Ackerman
Big Rock Partners Acquisition Corp.
May 5, 2021
Page 4
prescribed for the treatment of COVID-19.
13.We note your response to prior comment 18 and re-issue. Please revise the Business of
NeuroRx section, where appropriate, to disclose the nature of NeuroRx's material
intellectual property including the scope of the patent protection for NeuroRx's product
candidates and whether such patents are owned or licensed as well as the duration of any
patents, trademarks, licenses, franchises and concessions held by NeuroRx.
ZYESAMI Phase IIb/III Clinical Trial for treatment of Respiratory Failure in Critical COVID-
19, page 180
14.We note your statement on page 181 that ZYESAMI demonstrated a meaningful benefit in
survival after controlling for ventilation status and treatment site. Please revise to clearly
explain the meaning of the term "meaningful benefit" and whether the results were
statistically significant. Also explain why and how NeuroRx "controlled for ventilation
status and treatment site".  Present the results before controlling for ventilation status and
treatment site.
Initial Human Studies of ZYESAMI in COVID-19 with Respiratory Failure, page 186
15.Please revise your disclosure in this section to provide a brief overview of statistical
significance and how the FDA assesses whether trial data demonstrates statistical
significance.
16.We refer to a December 30, 2020 joint press release with Relief Therapeutics and a
February 23, 2021 article by Endpoints News (as updated on February 26, 2021) which
both indicate that in December 2020 FDA denied your September 2020 emergency use
authorization application.  Please advise or revise the prospectus summary, as well as
other appropriate sections of the prospectus, to discuss this regulatory determination,
including the stated basis, if any, for FDA’s decision.  Also revise the Business section to
present the 28-day data and discuss any and all changes to endpoints used during the
course of the clinical trial.
Critical COVID-19 with Respiratory Failure, page 192
17.We note your response to prior comment 23 and re-issue. Please revise your description of
the trial under this heading, as well as the trial under the heading "Critical COVID-19 with
Severe Comorbidity Expanded Access", to disclose who is conducting the trial, the phase
of the trial, the primary and secondary endpoints, metrics utilized, the number and nature
of any drug-related adverse events and the planned duration of the trial. To the extent any
of these trials has been completed, please disclose whether the trial achieved its primary
and secondary endpoints. If the disclosure in these sections is duplicative of disclosure
that appears elsewhere in the document, please consider removing this disclosure or
including a cross-reference.

 FirstName LastNameRichard Ackerman
 Comapany NameBig Rock Partners Acquisition Corp.
 May 5, 2021 Page 5
 FirstName LastName
Richard Ackerman
Big Rock Partners Acquisition Corp.
May 5, 2021
Page 5
General
18.Please ensure that the opinions and consents of both Marcum and KPMG are included in
your next amendment in order for the Staff to timely process it.
            You may contact Tracie Mariner at (202) 551-3744 or Al Pavot at (202) 551-3738 if you
have questions regarding comments on the financial statements and related matters. Please
contact Alan Campbell at (202) 551-4224 or Joe McCann at (202) 551-6262 with any other
questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:       Jeffrey M. Gallant, Esq.

CORRESP
1
filename1.htm

CORRESP

 Big Rock Partners Acquisition Corp.

2645 N. Federal Highway, Suite 230

Delray Beach, FL 33483

 (310) 734-2300

 April 16, 2021

Division of Corporation Finance

 Office of Life Sciences

Securities and Exchange Commission

 Washington, D.C. 20549

Re:

 Big Rock Partners Acquisition Corp.

Registration Statement on Form S-4

Filed January 27, 2021

 File No. 333-252479

 Ladies and Gentlemen:

Big Rock Partners Acquisition Corp. (“BRPA”) hereby responds as follows to the comment letter from the staff of the Securities
and Exchange Commission (the “Staff”) dated February 26, 2021, relating to the above-referenced Registration Statement on Form S-4 (the “Registration Statement”). For the
Staff’s convenience, we have recited each of the comments in the Staff’s letter below in bold and italics, and set forth the response in regular font immediately thereafter. We note that, given the current market uncertainty regarding the
accounting of warrants issued by special purpose acquisition companies, this submission is being made without the consent or audit report with respect to the financial statements included therein. We recognize that prior to requesting effectiveness
from the Staff we will be required to include those items in a subsequent amendment and request the Staff review the filing while the auditors review the accounting treatment of the warrants.

Capitalized terms used but not defined herein have the meanings ascribed to them in the Registration Statement.

Registration Statement on Form S-4

Cover Page

 1. Please revise your disclosure
here to clarify, if true, that ZYESAMI has not been approved by the FDA and is not commercialized.

 We have revised the disclosure on
the cover page of the prospectus included as part of the Registration Statement (the “prospectus”) as requested.

 2. Please revise the
prospectus cover page to disclose the expected ownership percentages in the combined company of BRPA’s public stockholders, the Sponsor and NeuroRx’s stockholders.

We have revised the disclosure on the cover page of the prospectus as requested.

Questions and Answers About the Proposals, page 7

3. We note your reference to a PIPE financing on pages 133 and 139. Please revise here or in the Prospectus Summary, as appropriate, to discuss the material
terms of the PIPE. Also, disclose, if applicable, whether the investors are affiliated with either of the constituent companies.

 We
respectfully inform the Staff that on March 12, 2021 BRPA entered into subscription agreements with certain qualified institutional buyers and institutional accredited investors (the “Investors”), pursuant to which BRPA will,
substantially concurrently with, and contingent upon, the consummation of the business combination with NeuroRx, Inc. (“NeuroRx”), issue to the Investors an aggregate of 1,000,000 shares of common stock of BRPA (the “Common
Stock”) at a price of $10.00 per share, for aggregate gross proceeds to BRPA of $10,000,000 (the “PIPE”). None of the Investors are affiliated with BRPA or NeuroRx. We have revised the disclosures on pages 24 and 106 of the
Registration Statement to discuss the material terms of the PIPE.

 I am a BRPA stockholder. Do I have conversion rights?, page 10

4. Please revise here and throughout the prospectus, where appropriate, to disclose the number of redemptions that would cause BRPA to fail to meet the net
tangible assets test.

 Assuming the PIPE is consummated substantially simultaneously with the consummation of the Merger, BRPA is
expected to meet the net tangible assets test even if all public stockholders exercise their conversion rights. We have revised the disclosures on pages 12, 29, 93, 95, 135 and 136 of the Registration Statement as requested.

Summary of the Proxy Statement / Prospectus / Consent Solicitation Statement, page 20

5. Please revise this section, where appropriate, to discuss Big Rock Partners Acquisition Corp.’s current listing on Nasdaq as well as the initial
listing application for the combined company that will be required in order for the combined company to be listed on Nasdaq. In addition, please disclose here and on the cover page when you will file the initial listing application for the combined
company and whether Nasdaq’s determination will be known at the time that stockholders are asked to vote on the merger agreement.

We have revised the disclosures on the cover page of the prospectus and on pages 6, 7 and 72 of the Registration Statement as requested.

Summary Historical Financial Information

BRPA, page 36

 6. We note that the third line
item in BRPA’s balance sheet data indicates that no shares of common stock were subject to possible redemption as of September 30, 2020. Elsewhere in the document, including on page 40, your disclosure indicates that 582,278 Public Shares
could be redeemed in connection with the Transactions. Please reconcile your disclosure or advise.

 We respectfully inform the Staff
that BRPA accounts for common stock subject to possible conversion in accordance with the guidance in Accounting Standards Codification (“ASC”) Topic 480 “Distinguishing Liabilities from Equity.” Common stock subject to mandatory
redemption (if any) is classified as a liability instrument and is measured at fair value. Conditionally redeemable common stock (including common stock that features redemption rights that are either within the control of the holder or subject to
redemption upon the occurrence of uncertain events not solely within our control) is classified as temporary equity. At all other times, common stock is classified as stockholders’ equity. BRPA’s common stock features certain redemption
rights that are considered to be outside of its control and subject to occurrence of uncertain future events. Accordingly, common stock subject to possible redemption is presented as temporary equity, outside of the stockholders’ equity section
of our condensed balance sheets. As of December 31, 2020, there are 552,742 Public Shares subject to possible redemption.

 Risk Factors

 We must enter into agreements with, and depend upon, one or more partners…, page 69

7. We note your statements that you must enter into a collaboration with one or more partners to assist you in any future product launches. Please revise
your disclosure to confirm whether it is planned that your collaboration agreement with Relief Therapeutics will be sufficient to commercialize ZYESAMI in the markets covered under the agreement.

We have revised the disclosures on page 69 of the Registration Statement as requested.

 Proposal No. 1 – The Business Combination Proposal

Merger Consideration, page 100

 8. We note your
disclosure that NeuroRx’s current securityholders have the contingent right to receive an aggregate of $100 million in cash upon the earlier of (i) FDA approval of NeuroRx’s COVID-19 drug
and the listing of that drug in the Orange Book and (ii) FDA approval of NeuroRx’s antidepressant drug regimen and the listing of that drug in the Orange Book, in each case, prior to December 31, 2022. Please revise or clarify whether
FDA approval of ZYESAMI or NRX-101 would trigger this earnout payment obligation. Please also revise to discuss how the combined company plans to meet this potential payment obligation if it is triggered,
including whether the $100 million is payable over a specified time period or must be paid immediately upon achievement of the earnout milestone.

We have revised the disclosures on page 103 of the Registration Statement as requested.

Background of the Transactions, page 103

 9.
Please identify the investment manager who introduced representatives of BRPA to representatives of NeuroRx and whether that investment manager is affiliated with either company.

We have revised the disclosures on pages 108 and 109 of the Registration Statement as requested.

Big Rock’s Board of Directors’ Reasons for Approval of the Merger Agreement, page 106

10. Please revise here and in the Summary to state the dollar value that the Board attributed to NeuroRx. To the extent that the Board relied exclusively on
the market valuation of Relief, revise the Summary to highlight that the Board did not conduct any additional financial or valuation analyses.

We have revised the disclosures on page 112 of the Registration Statement as requested.

Proposal No. 2 – The Charter Proposals

Required Vote to Amend the Charter, page 142

11. We note that you propose to amend your charter such that two-thirds of the voting power of all of the
outstanding shares of voting stock of NRX Pharmaceuticals will be required to amend or rescind “certain provisions” of the Proposed Charter. Please revise your disclosure to specify which Proposed Charter provisions would be subject to the
supermajority approval requirement.

 We have revised the disclosures on pages 8, 25, 91, 147, 148 and 284 of the Registration Statement
as requested.

 BRPA’s Management’s Discussion and Analysis of Financial Condition and Results of Operations

Liquidity and Capital Resources, page 168

 12.
Please revise to identify the “Investor”.

 We have revised the disclosures on page 174 of the Registration Statement as
requested.

 Beneficial Ownership of Securities of BRPA and NRX Pharmaceuticals, page 170

13. Please revise to disclose the beneficial ownership in the combined company held by officers and directors following the consummation of the
Transactions. Please also revise to disclose the ownership in the combined company held by Glytech, LLC and the affiliation between Glytech, LLC and Daniel Javitt.

We have revised the disclosures on pages 176 and 177 of the Registration Statement as requested.

 Business of NeuroRx, page 173

14. We note your references throughout to ZYESAMI, RLF-100, VIP and aviptadil. Based on the disclosure throughout
your document, each of these terms appears to be a reference to the same product candidate. To the extent this is true, revise your disclosure to refer to this product candidate consistently throughout. Alternatively, please revise the beginning of
this section to clearly explain the differences between ZYESAMI, RLF-100, VIP and aviptadil.

Aviptadil is the generic name for synthetically-manufactured VIP, as distinct from the natural peptide.
RLF-100 and ZYESAMI are both VIP-derived products, with ZYESAMI being a reformulation of RLF-100. We have revised the disclosures
on page 179 of the Registration Statement as requested, and we have revised the disclosures throughout the Registration Statement to distinguish ZYESAMI, RLF-100, VIP and aviptadil.

15. We note your statement that ZYESAMI’s “effectiveness” in COVID-19 is based on the principle that
the coronavirus specifically invades the Alveolar Type II cell of the pulmonary epithelium. Efficacy is a determination solely within the authority of the FDA or similar foreign regulators. You may present clinical trial end points and objective
data resulting from trials without concluding efficacy. Please revise this statement as well as any similar statements throughout this section, including your disclosure regarding NRX-101 on page 174 and the
header on page 180, to remove any implication that your product candidates have been found to be effective.

 We have revised the
disclosures on page 180 and 187 of the Registration Statement as requested, and we have revised the disclosures throughout the Registration Statement to remove any implication that NeuroRx’s product candidates have been found to be effective.

 16. We note the statement on page 173 that ZYESAMI is shown to increase the production of surfactant, block replication of SARS-CoV-2, block cytokine production and block cell death. Please revise to clarify whether NeuroRx conducted these pre-clinical
studies and, if not, who conducted them. We further note the statement that VIP is shown to have important potential effects in the treatment of other lung diseases. Please revise your disclosure to clarify whether NeuroRx is developing product
candidates for these other lung diseases.

 We have revised the disclosures on page 180 of the Registration Statement as requested.

17. We note your statement that the discovery underlying your approach is the synergy when NMDA antagonists are combined with inhibitors of the
brain’s 5-HT2A receptor. Please revise to state how this discovery was made and whether it has been observed or replicated in pre-clinical studies or clinical
trials.

 We have revised the disclosures on pages 180 and 181 of the Registration Statement as requested.

18. Please revise the Business of NeuroRx section, where appropriate, to disclose the nature of NeuroRx’s material intellectual property including the
scope of the patent protection for NeuroRx’s product candidates and whether such patents are owned or licensed as well as the duration of any patents, trademarks, licenses, franchises and concessions held by NeuroRx.

We have revised the disclosures on pages 179, 180 and 212 through 215 of the Registration Statement as requested.

Market Opportunity for Our Products

 ZYESAMI
(Aviptadil), page 176

 19. We note your statement here that the preliminary data for inhaled ZYESAMI are “positive” as well as your
statement on page 180 that management believes that the initial results of human studies of ZYESAMI are “encouraging.” Please revise to clarify the limitations of preliminary data, and revise to present the supporting preliminary data or
tell us where it currently appears in the document.

 We respectfully inform the Staff that the phase IIb/III randomized controlled
trial of ZYESAMI vs. placebo (NCT 04311697), conducted under FDA Fast Track designation, has achieved its primary and secondary endpoints, and the data is no longer preliminary. We have revised the disclosures on pages 181 and 182 of the
Registration Statement as requested.

 ZYESAMI (Aviptadil) Mechanism of Action, page 176

20. We note your statement that the Research Foundation of the State University of New York has agreed that it will not grant any other license to
Foundation Subject Matter that would allow any third-party to manufacture or sell products or services for the treatment of COVID-19 during the term of the License Agreement. Please revise here and on page 205
to state whether this agreement was made orally or in writing. Refer, if applicable, to Compliance Disclosure Interpretations, Regulation S-K, Question 146.04 concerning oral contracts.

We have revised the disclosures on pages 184 and 208 of the Registration Statement as requested.

21. We note your statement that VIP blocks the replication of coronavirus in the ATII cell and that it prevents cell death while increasing production of
surfactant. Please revise to clarify whether these effects were observed in pre-clinical studies or clinical trials and who conducted these studies or trials.

We have revised the disclosures on page 185 of the Registration Statement as requested.

Initial Human Studies of VIP in COVID-19 with Respiratory Failure, page 181

22. We note your comparison of the data from your Expanded Access Protocol (NCT04453839) to the results of the clinical trial of Remdesivir. As you have not
conducted head-to-head clinical trials, please revise to remove the comparison.

We have removed the comparison from the Registration Statement as requested.

Critical COVID-19 with Respiratory Failure, page 184

23. Please revise your description of the trial under this heading, as well as the trials under the headings “Critical
COVID-19 Prospective Multi-Center Trial” and “Critical COVID-19 with Severe Comorbidity Expanded Access” to disclose who is conducting the trial, the
phase of the trial, the primary and secondary endpoints, metrics utilized, the number and nature of any drug-related adverse events and the planned duration of the trail. To the extent any of these trials has been completed, please disclose whether
the trial ac

United States securities and exchange commission logo
February 26, 2021
Richard Ackerman
Chief Executive Officer
Big Rock Partners Acquisition Corp.
2645 N. Federal Highway, Suite 230
Delray Beach, FL 33483
Re:Big Rock Partners Acquisition Corp.
Registration Statement on Form S-4
Filed January 27, 2021
File No. 333-252479
Dear Mr. Ackerman:
            We have reviewed your registration statement 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 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-4
Cover Page
1.Please revise your disclosure here to clarify, if true, that ZYESAMI has not been approved
by the FDA and is not commercialized.
2.Please revise the prospectus cover page to disclose the expected ownership percentages in
the combined company of BRPA's public stockholders, the Sponsor and NeuroRx's
stockholders.
Questions and Answers About the Proposals, page 7
3.We note your reference to a PIPE financing on pages 133 and 139. Please revise here or in
the Prospectus Summary, as appropriate, to discuss the material terms of the PIPE.  Also,

 FirstName LastNameRichard Ackerman
 Comapany NameBig Rock Partners Acquisition Corp.
 February 26, 2021 Page 2
 FirstName LastNameRichard Ackerman
Big Rock Partners Acquisition Corp.
February 26, 2021
Page 2
disclose, if applicable, whether the investor or investors are affiliated with either of the
constituent companies.
I am a BRPA stockholder. Do I have conversion rights?, page 10
4.Please revise here and throughout the prospectus, where appropriate, to disclose the
number of redemptions that would cause BRPA to fail to meet the net tangible assets test.
Summary of the Proxy Statement / Prospectus / Consent Solicitation Statement, page 20
5.Please revise this section, where appropriate to discuss Big Rock Partners Acquisition
Corp.'s current listing on Nasdaq as well as the initial listing application for the combined
company that will be required in order for the combined company to be listed on Nasdaq.
In addition, please disclose here and on the cover page when you will file the initial listing
application for the combined company and whether Nasdaq's determination will be known
at the time that stockholders are asked to vote on the merger agreement.
Summary Historical Financial Information
BRPA, page 36
6.We note that the third line item in BRPA's balance sheet data indicates that no shares of
common stock were subject to possible redemption as of September 30, 2020. Elsewhere
in the document, including on page 40, your disclosure indicates that 582,278 Public
Shares could be redeemed in connection with the Transactions. Please reconcile your
disclosure or advise.
Risk Factors
We must enter into agreements with, and depend upon, one or more partners..., page 69
7.We note your statements that you must enter into a collaboration with one or more
partners to assist you in any future product launches. Please revise your disclosure to
confirm whether it is planned that your collaboration agreement with Relief Therapeutics
will be sufficient to commercialize ZYESAMI in the markets covered under the
agreement.
Proposal No. 1--The Business Combination Proposal
Merger Consideration, page 100
8.We note your disclosure that NeuroRX's current securityholders have the contingent right
to receive an aggregate of $100M in cash upon the earlier of (i) FDA approval of
NeuroRX's COVID-19 drug and the listing of that drug in the Orange Book and (ii) FDA
approval of NeuroRX's antidepressant drug regimen and the listing of that drug in the
Orange Book, in each case prior to December 31, 2022. Please revise to clarify whether
FDA approval of ZYESAMI or NRX-101 would trigger this earnout payment obligation.
Please also revise to discuss how the combined company plans to meet this potential
payment obligation if it is triggered, including whether the $100M is payable over a

 FirstName LastNameRichard Ackerman
 Comapany NameBig Rock Partners Acquisition Corp.
 February 26, 2021 Page 3
 FirstName LastNameRichard Ackerman
Big Rock Partners Acquisition Corp.
February 26, 2021
Page 3
specified time period or must be paid immediately upon achievement of the earnout
milestone.
Background of the Transactions, page 103
9.Please identify the investment manager who introduced representatives of BRPA to
representatives of NeuroRX and whether that investment manager is affiliated with either
company.
Big Rock’s Board of Directors’ Reasons for Approval of the Merger Agreement, page 106
10.Please revise here and in the Summary to state the dollar value that the Board attributed to
NeuroRx.  To the extent that the Board relied exclusively on the market valuation of
Relief, revise the Summary to highlight that the Board did not conduct any additional
financial or valuation analyses.
Proposal No. 2--The Charter Proposals
Required Vote to Amend the Charter, page 142
11.We note that you propose to amend your charter such that two-thirds of the voting power
of all of the outstanding shares of voting stock of NRX Pharmaceuticals will be required
to amend or rescind "certain provisions" of the Proposed Charter. Please revise your
disclosure to specify which Proposed Charter provisions would be subject to the
supermajority approval requirement.
BRPA's Management's Discussion and Analysis of Financial Condition and Results of
Operations
Liquidity and Capital Resources, page 168
12.Please revise to identify the "Investor".
Beneficial Ownership of Securities of BRPA and NRX Pharmaceuticals, page 170
13.Please revise to disclose the beneficial ownership in the combined company held by
officers and directors following the consummation of the Transactions. Please also revise
to disclose the ownership in the combined company held by Glytech, LLC and the
affiliation between Glytech, LLC and Daniel Javitt.
Business of NeuroRX, page 173
14.We note your references throughout to ZYESAMI, RLF-100, VIP and aviptadil. Based on
the disclosure throughout your document, each of these terms appears to be a reference to
the same product candidate. To the extent this is true, revise your disclosure to refer to this
product candidate consistently throughout. Alternatively, please revise the beginning of
this section to clearly explain the differences between ZYESAMI, RLF-100, VIP and
aviptadil.

 FirstName LastNameRichard Ackerman
 Comapany NameBig Rock Partners Acquisition Corp.
 February 26, 2021 Page 4
 FirstName LastNameRichard Ackerman
Big Rock Partners Acquisition Corp.
February 26, 2021
Page 4
15.We note your statement that ZYESAMI's "effectiveness" in COVID-19 is based on the
principle that the coronavirus specifically invades the Alveolar Type II cell of the
pulmonary epithelium.  Efficacy is a determination solely within the authority of the FDA
or similar foreign regulators. You may present clinical trial end points and objective data
resulting from trials without concluding efficacy. Please revise this statement as well as
any similar statements through this section, including your disclosure regarding NRX-101
on page 174 and the header on page 180, to remove any implication that your product
candidates have been found to be effective.
16.We note the statement on page 173 that ZYESAMI is shown to increase the production of
surfactant, block replication of SARS-CoV-2, block cytokine production and block cell
death. Please revise to clarify whether NeuroRx conducted these pre-clinical studies and,
if not, who conducted them. We further note the statement that VIP is shown to have
important potential effects in the treatment of other lung diseases. Please revise your
disclosure to clarify whether NeuroRx is developing product candidates for these other
lung diseases.
17.We note your statement that the discovery underlying your approach is the synergy when
NMDA antagonists are combined with inhibitors of the brain's 5-HT2A receptor. Please
revise to state how this discovery was made and whether it has been observed or
replicated in pre-clinical studies or clinical trials.
18.Please revise the Business of NeuroRx section, where appropriate, to disclose the nature
of NeuroRx's material intellectual property including the scope of the patent protection for
NeuroRx's product candidates and whether such patents are owned or licensed as well as
the duration of any patents, trademarks, licenses, franchises and concessions held by
NeuroRx.
Market Opportunity for Our Products
ZYESAMI (Aviptadil), page 176
19.We note your statement here that the preliminary data for inhaled ZYESAMI are
"positive" as well as your statement on page 180 that management believes that the initial
results of human studies of ZYESAMI are "encouraging." Please revise to clarify the
limitations of preliminary data, and revise to present the supporting preliminary data or
tell us where it currently appears in the document.
ZYESAMI (Aviptadil) Mechanism of Action, page 176
20.We note your statement that the Research Foundation of the State University of New York
has agreed that it will not grant any other license to Foundation Subject Matter that would
allow any third-party to manufacture or sell products of services for the treatment of
COVID-19 during the term of the License Agreement. Please revise here and on page 205
to state whether this agreement was made orally or in writing.  Refer, if applicable, to
Compliance Disclosure Interpretations, Regulation S-K, Question 146.04 concerning oral

 FirstName LastNameRichard Ackerman
 Comapany NameBig Rock Partners Acquisition Corp.
 February 26, 2021 Page 5
 FirstName LastNameRichard Ackerman
Big Rock Partners Acquisition Corp.
February 26, 2021
Page 5
contracts.
21.We note your statement that VIP blocks the replication of coronavirus in the ATII cell and
that it prevents cell death while increasing production of surfactant. Please revise to
clarify whether these effects were observed in pre-clinical studies or clinical trials and
who conducted these studies or trials.
Initial Human Studies of VIP in COVID-19 with Respiratory Failure, page 181
22.We note your comparison of the data from your Expanded Access Protocol
(NCT04453839) to the results of the clinical trial of Remdesivir. As you have not
conducted head-to-head clinical trials, please revise to remove the comparison.
Critical COVID-19 with Respiratory Failure, page 184
23.Please revise your description of the trial under this heading, as well as the trials under the
headings "Critical COVID-19 Prospective Multi-Center Trial" and "Critical COVID-19
with Severe Comorbidity Expanded Access" to disclose who is conducting the trial, the
phase of the trial, the primary and secondary endpoints, metrics utilized, the number and
nature of any drug-related adverse events and the planned duration of the trial. To the
extent any of these trials has been completed, please disclose whether the trial achieved its
primary and secondary endpoints.
Product Development and Manufacturing, page 191
24.Your disclosure on page 191 indicates that you have signed an exclusive supply
agreement with Nephron Pharmaceuticals for the supply of aviptadil and that you have
signed exclusive distribution agreement with Cardinal Health for the warehousing and
distribution of aviptadil in the United States and Puerto Rico. Please describe the material
terms of these agreements and file them as exhibits to the registration statement.
Summary of NeuroRx Material In-licensing Obligations, page 201
25.Please file the agreements referenced in this section as exhibits to the registration
statement.
Management of NeuroRx
Executive Employment Arrangements, page 228
26.Please file the employment agreements with Dr. Javitt and Mr. Del Buono and the "Work
For Hire" agreement with Mr. Besthof as exhibits to the registration statement.
NeuroRx's Management's Discussion and Analysis of Financial Condition and Results of
Operations
Liquidity and Capital Resources, page 240
27.We note your statement that you generated financial projections in partnership with

 FirstName LastNameRichard Ackerman
 Comapany NameBig Rock Partners Acquisition Corp.
 February 26, 2021 Page 6
 FirstName LastNameRichard Ackerman
Big Rock Partners Acquisition Corp.
February 26, 2021
Page 6
IQVIA that estimate potential gross sales in excess of $1.4 billion for the treatment of
COVID-19 in the United States. Please revise to disclose the time period over which these
gross sales are projected to be realized. Please also provide the consent of IQVIA in
accordance with Rule 436.
Material U.S. Federal Tax Consequences, page 257
28.Please revise to state, if true, that the disclosure in this section represents the opinion of
Paul, Weiss, Rifkind, Wharton & Garrison LLP.  In this regard, your disclosure on pages
33 and 258 indicates that counsel's opinion is limited to whether the transaction will
qualify as a “reorganization” within the meaning of Section 368(a) of the tax code.  As
such it is not clear whether the tax opinion covers the tax consequences of the Merger to
U.S. Holders of NeuroRx Capital Stock who exchange their shares.  It is similarly unclear
whether counsel's tax opinion extends to BRPA Stockholders who redeem their shares.
Please refer to Sections III.B and III.C.3 of Staff Legal Bulletin No. 19 for additional
guidance.
Description of Capital Stock of NRX Pharmaceuticals, page 276
29.Please revise this section or another section in the body of the prospectus, as appropriate,
to describe the material terms of the share subscription facility agreement referred to on
page F-54 and file the share subscription agreement as an exhibit to the registration
statement. In your revisions, please state whether the share-lending option and the warrant
issuance obligation would be triggered by the consummation of the transactions described
in the registration statement as well as the exercise price of the warrants. Alternatively,
please tell us why this description and the filing of the share subscription agreement
would not be required.
            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.

 FirstName LastNameRichard Ackerman
 Comapany NameBig Rock Partners Acquisition Corp.
 February 26, 2021 Page 7
 FirstName LastName
Richard Ackerman
Big Rock Partners Acquisition Corp.
February 26, 2021
Page 7
            You may contact Tracie Mariner at (202) 551-3744 or Al Pavot at (202) 551-3738 if you
have questions regarding comments on the financial statements and related matters.  Please
contact Alan Campbell at (202) 551-4224 or Joe McCann at (202) 551-6262 with any other
questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:       Jeffrey M. Gallant, Esq.

CORRESP
1
filename1.htm

brpa_corres

Graubard
Miller

The
Chrysler Building

405
Lexington Avenue

New York, N.Y. 10174-1101

(212)
818-8800

facsimile

direct
dial number

(212)
818-8881

(212)
818-8638

email
address

jgallant@graubard.com

December 7,
2020

Division
of Corporation Finance

Office
of Real Estate & Construction

Securities
and Exchange Commission

100 F
Street, N.E.

Washington,
D.C. 20549

Re:

Big
Rock Acquisition Corp.

Preliminary
Proxy Statement on Schedule 14A

Filed
November 25, 2020

File
No. 001-38302

Ladies
and Gentlemen:

On
behalf of Big Rock Acquisition Corp. (“Company”), we
respond as follows to the Staff’s comment letter, dated
December 4, 2020, relating to the above-captioned Preliminary Proxy
Statement on Schedule 14A (“Preliminary Proxy
Statement”).

Please
note that for the Staff’s convenience, we have recited each
of the Staff’s comments and provided the Company’s
response to each comment immediately thereafter.

Preliminary Proxy Statement on Schedule 14A

General

1.

We note that you may not be able to continue to meet the listing
standards of Nasdaq. Please disclose the effects of being delisted
from Nasdaq on shareholders who elect not to redeem including, for
example, on the stock price and liquidity. Please also clearly
disclose which Nasdaq requirements would continue to apply to your
company in the event you are delisted, such as the requirement that
the initial business combination be with a company that had an
aggregate fair market value of 80% of the assets held in the trust
account. Lastly, disclose the risk that redemptions in connection
with this shareholder vote would further reduce the amount held in
the trust and the impact that would have upon your ability to find
a business combination.

We have
revised the disclosure of the Preliminary Proxy Statement on pages
4, 7 and 14 as requested.

*************

If
you have any questions, please do not hesitate to contact me at the
above telephone and facsimile numbers.

Sincerely,

/s/
Jeffrey M. Gallant

Jeffrey
M. Gallant

cc:

Mr. Richard
Ackerman

United States securities and exchange commission logo
December 7, 2020
Richard Ackerman
Chief Executive Officer
Big Rock Partners Acquisition Corp.
2645 N. Federal Highway, Suite 230
Delray Beach, Florida 33483
Re:Big Rock Partners Acquisition Corp.
Preliminary Proxy Statement on Schedule 14A
Filed November 25, 2020
File No. 001-38302
Dear Mr. Ackerman:
            We have completed our review of your filing.  We remind you that the company and its
management are responsible for the accuracy and adequacy of their disclosures, notwithstanding
any review, comments, action or absence of action by the staff.
Sincerely,
Division of Corporation Finance
Office of Real Estate & Construction
cc:       Jeffrey Gallant

United States securities and exchange commission logo
December 4, 2020
Richard Ackerman
Chief Executive Officer
Big Rock Partners Acquisition Corp.
2645 N. Federal Highway, Suite 230
Delray Beach, Florida 33483
Re:Big Rock Partners Acquisition Corp.
Preliminary Proxy Statement on Schedule 14A
Filed November 25, 2020
File No. 001-38302
Dear Mr. Ackerman:
            We have reviewed your filing and have the following comment.  In our comment, we
may ask you to provide us with information so we may better understand your disclosure.
            Please respond to this comment within ten business days by providing the requested
information or advise us as soon as possible when you will respond.  If you do not believe our
comment applies to your facts and circumstances, please tell us why in your response.
            After reviewing your response to this comment, we may have additional comments.
Preliminary Proxy Statement on Schedule 14A
General
1.We note that you may not be able to continue to meet the listing standards of Nasdaq.
Please disclose the effects of being delisted from Nasdaq on shareholders who elect not to
redeem including, for example, on the stock price and liquidity.  Please also clearly
disclose which Nasdaq requirements would continue to apply to your company in the
event you are delisted, such as the requirement that the initial business combination be
with a company that had an aggregate fair market value of 80% of the assets held in the
trust account.  Lastly, disclose the risk that redemptions in connection with this
shareholder vote would further reduce the amount held in the trust and the impact that
would have upon your ability to find a business combination.

 FirstName LastNameRichard Ackerman
 Comapany NameBig Rock Partners Acquisition Corp.
 December 4, 2020 Page 2
 FirstName LastName
Richard Ackerman
Big Rock Partners Acquisition Corp.
December 4, 2020
Page 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.
            Please contact Ronald (Ron) E. Alper at 202-551-3329 or Brigitte Lippmann at 202-551-
3713 with any other questions.
Sincerely,
Division of Corporation Finance
Office of Real Estate & Construction
cc:       Jeffrey Gallant

CORRESP
1
filename1.htm

Blueprint

November
16, 2017

Securities
and Exchange Commission

100 F
Street, N.E.

Washington,
D.C. 20549

Re:

Big Rock Partners
Acquisition Corp.

Registration
Statement on Form S-1

File No.

333-220947

Ladies
and Gentlemen:

Pursuant
to Rule 461 of the General Rules and Regulations promulgated under
the Securities Act of 1933, as amended, Big Rock Partners
Acquisition Corp. (the “Company”) hereby requests
that its Registration Statement on Form S-1, as amended (File No.
333-220947) filed with the Securities and Exchange Commission (the
“Commission”) be declared
effective by the Commission on or before Noon Eastern Time, Monday,
November 20, 2017, or as soon thereafter as practical.

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 Company acknowledges that
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. The Company
acknowledges that it 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.

Once
the Registration Statement is declared effective, please orally
confirm that event with our counsel, Akerman LLP by calling
Christina Russo at (305) 982-5531.

Very
truly yours,

BIG
ROCK PARTNERS ACQUISITION CORP.

By:/s/
Richard Ackerman

Name:
Richard Ackerman

Title:
Chief Executive Officer

CORRESP
1
filename1.htm

Blueprint

EARLYBIRDCAPITAL,
INC.

366
Madison Avenue | 8th Floor

New
York, NY 10017

November 16,
2017

VIA EDGAR

Securities and Exchange Commission

100 F. Street, N.E.

Washington, D.C. 20549

Attn: Amanda Ravitz

Re:

Big Rock Partners Acquisition Corp. (the "Company")

Registration Statement on Form S-1

(File No. 333-220947) (the "Registration Statement")

Dear
Ms. Ravitz:

In
connection with the Registration Statement on Form S-1 of Big Rock
Partners Acquisition Corp., the undersigned, which is acting as the
representative of the underwriters of the offering, hereby requests
acceleration of the effective date and time of the Registration
Statement to 12:00 P.M., Monday, November 20, 2017 or as soon
thereafter as practicable, pursuant to Rule 461 of the Securities
Act of 1933.

Very truly
yours,

EARLYBIRDCAPITAL,
INC.

By:

/s/
Steven
Levine

Name:

Steven
Levine

Title:

CEO

CORRESP
1
filename1.htm

Blueprint

EARLYBIRDCAPITAL, INC.

366 Madison Avenue | 8th Floor

New York, NY 10017

November 16,
2017

VIA EDGAR

Securities
and Exchange Commission

100 F.
Street, N.E.

Washington,
D.C. 20549

Attn:
Amanda Ravitz

Re:

Big Rock Partners Acquisition Corp. (the "Company")

Registration Statement on Form S-1

(File No. 333-220947) (the "Registration Statement")

Dear
Ms. Ravitz:

In
accordance with the provisions of Rule 460 under the Securities Act
of 1933, the undersigned, as representative of the underwriters of
the proposed offering of securities of Big Rock Partners
Acquisition Corp., hereby advises that copies of the Preliminary
Prospectus, dated November 14, 2017, were distributed on or about
November 14, 2017, as follows:

235 to
individual investors;

108 to
FINRA members (which included 28 prospective underwriters and
selected dealers); and

49 to
institutions.

The
undersigned has been informed by the participating dealers that, in
accordance with Rule 15c2-8 under the Securities Exchange Act of
1934, copies of the Preliminary Prospectus, dated November 14,
2017, have been distributed to all persons to whom it is expected
that confirmations of sale will be sent; and we have likewise so
distributed copies to all customers of ours. We have adequate
equity to underwrite a “firm commitment”
offering.

Very truly
yours,

EARLYBIRDCAPITAL,
INC.

By:

/s/
Steven
Levine

Name:

Steven
Levine

Title:

CEO

CORRESP
1
filename1.htm

Blueprint

Michael
Francis

Akerman
LLP

Las
Olas Centre II, Suite 1600

350
East Las Olas Boulevard

Fort
Lauderdale, FL 33301-2999

T: 954
463 2700

F: 954
463 2224

November
14, 2017

VIA EDGAR

Amanda
Ravitz

Assistant
Director

Office
of Electronics and Machinery

United
States Securities and Exchange Commission

Division
of Corporation Finance

Mail
Stop 3030

Washington,
D.C. 20549

Re:

Big Rock Partners Acquisition Corp.

Registration Statement on Form S-1

Filed October 13, 2017

File No. 333-220947

Dear Ms. Ravitz:

On
behalf of Big Rock Partners Acquisition Corp. (the "Company"), we
hereby respond to the Staff's comment letter, dated November 9,
2017, regarding the Company's Registration Statement on Form S-1
filed on October 13, 2017. Please note that we are simultaneously
filing Amendment No. 1 to the Registration Statement on Form S-1
(“Amendment No. 1”).

Please
note for your convenience, we have recited the Staff's comments in
boldface type and provided the Company's response to the comment
immediately thereafter.

Prospectus Cover

1.

We
note your disclosure on your prospectus cover that you applied to
have your units listed on the Nasdaq Capital Market on or promptly
after the date of this prospectus. Given several features of the
offered securities appear to rely to a certain extent upon such
listing, including protection of the funds in the trust as well as
liquidity of the trading market, clearly highlight the risks of not
so listing throughout in appropriate locations, including the
summary. In addition, since the listing does not appear to be a
condition to completion of this offering, it does not appear
appropriate to highlight Nasdaq listing as you have
done.

Amanda
Ravitz

Assistant
Director

Office
of Electronics and Machinery

November
14, 2017

Page
2

In
response to the Staff’s comment, we hereby confirm that in
the event that the Company’s securities are not approved for
listing on Nasdaq Capital Market (“NASDAQ”), the
Company would not proceed with this offering. As such, we do not
believe that there is a need to highlight the risks of not listing
on NASDAQ and we believe it is appropriate to highlight the NASDAQ
listing and NASDAQ rules as we have done.

Business Strategy, page 1

2.

Please
expand the appropriate section to explain what you mean by the
phrase “differentiated deal flow” mentioned in the
third paragraph on page 2.

In
response to the Staff’s comment, we have revised the language
in this section and elsewhere, as appropriate.

JOBS Act, page 5

3.

Please
supplementally provide us with copies of all written
communications, as defined in Rule 405 under the Securities Act,
that you or anyone authorized to do so on your behalf, present to
potential investors in reliance on Section 5(d) of the Securities
Act, whether or not they retain copies of the
communications.

We will
supplementally provide the Staff with copies of all such written
communications under separate cover. We further advise the Staff
that investors will not retain copies of any such
materials.

Liquidation if no business combination, page 11

4.

Please
tell us why your statement in this section and elsewhere that you
have "not independently verified" that A/Z Property Partners, LLC
has sufficient funds to satisfy its indemnity obligations is
appropriate in view of your disclosure that A/Z Property Partners
is an entity majority owned by Richard Ackerman.

In
response to the Staff’s comment, we have revised the language
in this section and elsewhere, as appropriate.

Amanda
Ravitz

Assistant
Director

Office
of Electronics and Machinery

November
14, 2017

Page
3

Risk Factors, page 14

5.

Given
your disclosure on page 2 and elsewhere that you intend to focus on
companies in the senior housing and care industry in the United
States, please add risk factors that highlight the materials risks
concerning companies in that industry.

In
response to the Staff’s comment, we have added risk factors
that highlight the material risks concerning companies in the
senior housing and care industry.

Management, page 56

6.

Please
explain what you mean by the terms “Class A” senior
housing communities and “triple-net leased properties focused
on the post-acute sector.”

In
response to the Staff’s comment, we have revised the language
in this section.

7.

Please
ensure that the information about your management team’s
experience is balanced, with equally prominent discussion of any
management experience with similar transactions initiated but
abandoned, unsuccessful transactions, or transactions or entities
that generated losses for investors.

In
response to the Staff’s comment, we have revised the language
in this section.

Conflicts of Interest, page 60

8.

Please
expand the disclosure in this section to include a table that
summarizes the entities to which your executive officers, directors
and director nominees currently have fiduciary duties or
obligations.

In
response to the Staff’s comment, we have included the
requested table.

Underwriting Discount, page 81

9.

We
note your disclosure in this section about changing the offering
price and other selling terms. If true, please revise to clarify
that you are referring to changes after completion of this
offering.

In
response to the Staff’s comment, we have revised the language
to clarify that we are referring to changes after completion of
this offering.

Amanda
Ravitz

Assistant
Director

Office
of Electronics and Machinery

November
14, 2017

Page
4

* *
* * * * * * * * * * *

If you
have any questions, please call me at 305.982.5581.

Sincerely,

AKERMAN, LLP

/s/
Michael Francis

For the
Firm

cc:

Andri
Carpenter

United
States Securities and Exchange Commission

Brian
Cascio, Accounting Brach Chief

United
States Securities and Exchange Commission

Tom
Jones

United
States Securities and Exchange Commission

Daniel
Morris, Special Counsel

United
States Securities and Exchange Commission

Richard
Ackerman, Chairman, President and Chief Executive
Officer

Big Rock Partners Acquisition
Corp.

Lori
Wittman, Chief Financial Officer

Big Rock Partners Acquisition
Corp.

Christina C. Russo, Esq.

Akerman
LLP

Mail Stop 3030
November 9, 2017
.
Via E -mail
Richard Ackerman
Chairman, President and Chief Executive Officer
Big Rock Partners Acquisition Corp.
2645 N. Federal Highway
Suite 230
Delray Beach, Florida 33483

Re: Big Rock Partners Acquisition Corp.
Registration Statement on Form S -1
Filed October 13, 2017
  File No. 333 -220947

Dear Mr. Ackerman :

We have reviewed your registration statement 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 amending your registration statement and providing the
requested information .  If you do not believe our comm ents 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.

Prospectus Cover

1. We note your disclosure on your prospectus cover that you applied to have your units
listed on the Nasdaq Capital Market on or promptly after the date of this prospectus.
Given several features of the of fered securities appear to rely to a certain extent upon
such listing, including protection of the funds in the trust as well as liquidity of the
trading market, clearly highlight the risks of not so listing throughout in appropriate
locations, including t he summary. In addition, since the listing does not appear to be a
condition to completion of this offering, it does not appear appropriate to highlight
Nasdaq listing as you have done.

Richard Ackerman
Big Rock Partners Acquisition Corp.
November 9, 2017
Page 2

 Business Strategy, page 1

2. Please expand the appropriate section to explain what you mean by the phrase
“differentiated deal flow” mentioned in the third paragraph on page 2.

JOBS Act, page 5

3. Please supplementally provide us with copies of all written communications, as defined
in Rule 405 under the Securities Act, that you or anyone authorized to do so on your
behalf, present to potential investors in reliance on Section 5(d) of the Securities Act,
whether or not they retain copies of the communications.

Liquidation if no business combination, page 11

4. Please tell us why your statement in this section and elsewhere that you have "not
independently verified" that A/Z Property Partners, LLC has sufficient funds to satisfy its
indemnity obligations is appropriate in view of your disclosure that A/Z Property Partners
is an entity majority owned by Richard Ackerman.

Risk Factors, page 14

5. Given your disclosure on page 2 and elsewhere that you intend to focus on companies in
the senior housing and care industry in the United States, please add risk factors that
highlight t he materials risks concerning companies in that industry.

Management, page 56

6. Please explain what you mean by the terms “Class A” senior housing communities and
“triple -net leased properties focused on the post -acute sector.”

7. Please ensure that the information about your management team’s experience is balanced,
with equally prominent discussion of any management experience with similar
transactions initiated but abandoned, unsuccessful transactions, or transactions or entities
that generated losses for investors.

Conflicts of Interest, page 60

8. Please expand the disclosure in this section to include a table that summarizes the entities
to which your executive officers, directors and director nominees currently have fiduciary
duties or obligations.

Richard Ackerman
Big Rock Partners Acquisition Corp.
November 9, 2017
Page 3

 Underwriting Discount, page 81

9. We note your disclosure in this section about changing the offering price and other
selling terms.  If true, please revise to clarify that you are referring to changes after
completion of this offering.

 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.

You may contact Andri Carpenter at (202) 551 -3645 or Brian Cascio, Accounting Branch
Chief, at (202) 551 -3676 if you have questions re garding comments on the financial statements
and related matters.  Please contact Tom Jones at (202) 551 -3602 or Daniel Morris, Special
Counsel, (202) 551 -3314 with any other questions.

Sincerely,

 /s/ Daniel Morris for

 Amanda Ravitz
Assistant Directo r
Office of Electronics and Machinery

cc:    Michael Francis, Esq.