NeuroRx, Inc. entered into letter of intent to acquire Big Rock Partners Acquisition Corp. (NasdaqCM:BRPA) from BRAC Lending Group LLC, EarlyBirdCapital, Inc., Big Rock and others for approximately $980 million in a reverse merger transaction on November 14, 2020. NeuroRx, Inc. entered into an agreement to acquire Big Rock Partners Acquisition Corp. (NasdaqCM:BRPA) in a reverse merger transaction on December 13, 2020. Under the terms of the agreement, the total consideration of the transaction is valued at approximately $530 million plus approximately $350 million additional consideration based on projected milestones. Big Rock will issue to NeuroRx's current equity holders an aggregate of 50 million shares of Big Rock common stock for their interests in NeuroRx, representing $500 million of equity consideration, assuming a value of $10 per common share. Subject to certain conditions, an aggregate of 25 million additional shares of Big Rock common stock will be issued to NeuroRx pre-merger equity holders if, prior to December 31, 2022, (1) RLF-100 receives emergency use authorization by the FDA and (2) the FDA accepts the NeuroRx filing of its application to approve RLF-100. In addition, subject to certain conditions, a $100 million cash earnout may be payable to NeuroRx pre-merger equity holders if, prior to December 31, 2022, either (1) FDA approval of the NeuroRx COVID-19 Drug is obtained and the NeuroRx COVID-19 Drug is listed in the FDA's "Orange Book" or (2) FDA approval of the NeuroRx Antidepressant Drug Regimen is obtained and the NeuroRx Antidepressant Drug Regimen is listed in the FDA's "Orange Book". Immediately after the Closing, NeuroRx's stockholders will hold approximately 95% of the issued and outstanding Common Stock and the current stockholders of BRPA will hold approximately 5% of the issued and outstanding Common Stock of the combined company. The agreement may be terminated at any time prior to the Closing as follows: by written notice from either BRPA or NeuroRx if the transactions are not consummated on or before April 23, 2021 or by written notice from NeuroRx to BRPA if Extension Approval is not obtained by December 24, 2020. In connection with the Merger, BRPA will change its name to NRX Pharmaceuticals, Inc., with stockholders of NeuroRx becoming stockholders of NRX Pharmaceuticals. If NeuroRx terminates the agreement in order to enter into a definitive agreement for a superior proposal, BRPA will be entitled to receive a termination fee in the amount of $10 million. Under the terms of the transaction, Big Rock and NeuroRx will merge and post-approvals, the common stock and warrants will be traded on Nasdaq under the symbols “NRXP” and “NRXPW”, respectively.

Post transaction NeuroRx's management team will comprise of Founder, Chairman & Chief Executive Officer Jonathan C. Javitt; William Fricker, Chief Financial Officer and Treasurer; Robert Besthof as Chief Commercial and Patient Officer and Head of Operations, and Alessandra Daigneault as Corporate Secretary, who are expected to continue to run the combined company. All officers and members of the Board of Directors of Big Rock will resign in connection with the closing of the transactions. The Board of Directors of the combined company will consist of Jonathan Javitt, Sherry A. Glied, Patrick J. Flynn, Daniel Troy, Aaron Gorovitz and Chaim Hurvitz. The corporate headquarters and principal executive offices of BRPA will be located at 1201 N. Market Street, Suite 111, Wilmington, DE 19801.

Completion of the transaction is subject to approval by stockholders of NeuroRx and Big Rock and other customary closing conditions includes all specified waiting periods under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended shall have expired; BRPA shall have at least $5,000,001 of net tangible assets; the registration statement, of which this proxy statement / prospectus / consent solicitation statement forms a part, shall have become effective; each ancillary agreement required to be executed by the Merger Agreement shall have been executed and delivered by the parties thereto; BRPA shall be and remain listed on Nasdaq and BRPA's application to list the shares of Common Stock to be issued in connection with the Transactions (including the Earnout Shares) shall have been approved by Nasdaq, subject to official notice thereof and public holder requirements and the resignation of each officer and director of BRPA as of the Effective Time. The Boards of Directors of both NeuroRx and Big Rock have unanimously approved the proposed transaction. The special meeting of stockholders of Big Rock Partners Acquisition will be held on April 23, 2021 to approve a proposal to amend the Company's amended and restated certificate of incorporation, as amended to extend the date by which the Company has to consummate a business combination. The Board of Directors of Big Rock Partners Acquisition Corp. unanimously recommended that stockholders vote “FOR” the approval of the extension amendment proposal. As of May 20, 2021, the shareholder meeting of Big Rock Partners is scheduled on May 24, 2021. As of May 21, 2021, the waiting period under the HSR Act expired on March 15, 2021. As of May 21, 2021, registration statement on Form S-4 was declared effective. The transaction is expected to occur in the first or second quarter of 2021.

EarlyBirdCapital acted as financial advisor to Big Rock and David Alan Miller and Jeffrey M. Gallant of Graubard Miller acted as legal advisors to Big Rock in the transaction. Big Rock will pay EarlyBirdCapital a cash fee of $2.76 million for such services upon the consummation of a Business Combination in an amount equal to 4% of the gross proceeds of the Initial Public Offering. David S. Huntington and David A. Curtiss of Paul, Weiss, Rifkind, Wharton & Garrison LLP acted as legal advisors to NeuroRx in the transaction. Karen Smith of Advantage Proxy, Inc. acted as information agent and Mark Zimkind of Continental Stock Transfer & Trust Company acted as transfer agent for Big Rock Partners. Big Rock Partners will pay a fee of $5,500 to Advantage Proxy, Inc. for the foregoing services.

NeuroRx, Inc. completed the acquisition of Big Rock Partners Acquisition Corp. (NasdaqCM:BRPA) from BRAC Lending Group LLC, EarlyBirdCapital, Inc., Big Rock and others in a reverse merger transaction on May 24, 2021. As a result of the transaction, the resulting issuer will undergo a name change and CUSIP number. In conjunction with the change of name, the common stock and warrant will be listed on the Nasdaq Global Market. The right (BRPAR) and Unit (BRPAU) will be suspended from listing. As of May 25, 2021, , NeuroRx, Inc., announced it has been approved by the Nasdaq for listing on the Nasdaq Global Market, following the completion of its business combination
and the combined company commenced trading on Nasdaq under name NRx Pharmaceuticals, Inc. and ticker NRXP.