First Amendment to the Services Convertible Promissory Note, dated March 25, 2020, between Virpax Pharmaceuticals, Inc. and RRD International, LLC

Exhibit 10.25

FIRST AMENDMENT TO THE SERVICES CONVERTIBLE PROMISSORY NOTE

BETWEEN VIRPAX PHARMACEUTICALS, INC. AND RRD INTERNATIONAL, LLC

This First Amendment to the Services Convertible Promissory Note (Exhibit A to the Service Provider Convertible Note Purchase Agreement dated August 29, 2019, this “Amendment”) is entered into on March 25, 2020 (the “Effective Date”) between Virpax Pharmaceuticals, Inc., (the “Virpax”) and RRD International, LLC (“RRD”). Virpax and RRD may be collectively referred to herein as the “Parties.”

W I T N E S S E T H:

WHEREAS, the Parties entered into that certain Services Convertible Promissory Note dated August 29, 2019, (the “Note”) which described the terms under which RRD would loan certain amounts to Virpax the terms under which Virpax would repay such amounts; and

WHEREAS, the Parties desire to amend the Note in order to: (1) amend the definitions of Qualified Financing and Conversion Date to extend the dates therein from March 31, 2020 to September 30, 2020; (2) amend the definition of Maximum in order to increase the amount of principal from $400,000 to $600,000; (3) amend the terms of conversion to provide for RRD, at its option, to convert the note into equity or cash (all or in part) upon a Qualified Financing or upon the Conversion Date; and (4) provide for the payment of all interest accrued up to March 31, 2020.

NOW THEREFORE, the Parties in consideration of the mutual covenants and agreements hereinafter set forth agree as follows:

“Unless earlier converted as provided in this Services Note, this Services Note shall be due and payable immediately without presentment, demand, protest or notice of any kind, all of which are hereby expressly waived by the Company, and the Service Provider then may, immediately and without expiration of any period of grace, enforce payment of all amounts due and owing under the Services Note and exercise any and all other remedies granted to the Service Provider at law, in equity or otherwise upon the earlier of: (a) the date of the Qualified Financing (as defined below); (b) an Event of Default (as defined below); or (c) a Change in Control (as defined below). Upon enforcement, Service Provider shall have the option to receive cash or convert any or all of the principle and accrued interest to Qualified Securities as defined below.”

“Upon a Qualified Financing, Service Provider shall have the option to convert any or all of the principle and accrued interest to Qualified Securities as defined below.”

Immediately upon execution of this Amendment, Virpax shall pay to RRD all interest accrued up to March 31, 2020 ($16,435) as further described in Exhibit B.

IN WITNESS WHEREOF, the Parties have caused this Amendment to be executed by their duly authorized representatives as of the Effective Date.

ACKNOWLEDGED, ACCEPTED AND AGREED TO:

Exhibit A

Amended and restated Exhibit A to the Note as of March 27, 2020

Exhibit B

Calculation of interest accrued up to March 31, 2020 ($16,435)

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