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                            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,
 Richard Ackerman
FirstName LastNameRichard
Big Rock Partners AcquisitionAckerman
                              Corp.
Comapany26,
February  NameBig
            2021 Rock Partners Acquisition Corp.
February
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         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
 Richard Ackerman
FirstName LastNameRichard
Big Rock Partners AcquisitionAckerman
                              Corp.
Comapany26,
February  NameBig
            2021 Rock Partners Acquisition Corp.
February
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         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.
 Richard Ackerman
FirstName LastNameRichard
Big Rock Partners AcquisitionAckerman
                              Corp.
Comapany26,
February  NameBig
            2021 Rock Partners Acquisition Corp.
February
Page 4 26, 2021 Page 4
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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
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Big Rock Partners AcquisitionAckerman
                              Corp.
Comapany26,
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            2021 Rock Partners Acquisition Corp.
February
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         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
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Big Rock Partners AcquisitionAckerman
                              Corp.
Comapany26,
February  NameBig
            2021 Rock Partners Acquisition Corp.
February
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         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.
 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,
FirstName LastNameRichard Ackerman
                                                         Division of
Corporation Finance
Comapany NameBig Rock Partners Acquisition Corp.
                                                         Office of Life
Sciences
February 26, 2021 Page 7
cc:       Jeffrey M. Gallant, Esq.
FirstName LastName