Amendment, dated March 9, 2022, to the Share Purchase Agreement, by and among Synthetic Biologics, Inc., VCN Biosciences, S.L. and the shareholders of VCN Biosciences, S.L., dated December 14, 2021

Exhibit 2.2

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AMENDMENT TO SHARE PURCHASE AGREEMENT

This AMENDMENT (the “Amendment”) is made and entered into as of the 9^th day of
March, 2022 to the SHARE PURCHASE AGREEMENT, dated December 14, 2021 (the “Agreement”), by and among Synthetic Biologics, Inc., a Nevada corporation (the “Purchaser”), VCN Biosciences, S.L., a corporation organized under the laws of Spain (the “Company”), and each of the shareholders of the Company (collectively, the “Shareholders”). Capitalized terms used and not defined herein shall have the meanings ascribed to them in the Agreement.

WHEREAS, Section 13.3 of the Agreement provides that prior to the Closing the Agreement may be amended by written agreement among the Purchaser, the Company and the Shareholders.

NOW, THEREFORE, for good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, the parties hereto agree as follows:

1.            Section 1.2(a) of the Agreement is hereby deleted in its entirety and replaced with the following:

“At the Closing, the Purchaser shall deliver to (i) Grifols Innovation and New Technologies Limited (“Grifols”) the Closing Cash Consideration by means of wire transfer of immediately available funds to an account or accounts designated by Grifols; (ii) the creditors of VCN set forth on Schedule 1.2 hereto (the “VCN Creditors”) evidence of registration with the Purchaser’s transfer agent of shares of Purchaser Common Stock in the name of each such creditor, in each case for such number of shares of Purchaser Common Stock set forth opposite such creditors name on Schedule 1.2 hereto; and (iii) the Remaining Shareholders evidence of registration with the Purchaser’s transfer agent of shares of Purchaser Common Stock in the name of each Remaining Shareholder, in each case for such number of shares of Purchaser Common Stock set forth opposite such Remaining Shareholder’s name on Schedule 1.2 hereto (collectively, the “Closing Consideration”); provided, however, it shall be a condition to any issuance of Purchaser Common Stock to the VCN Creditors that Purchaser shall have received from each such creditor a written representation and warranty, in form and substance acceptable to Purchaser, with respect to the matters set forth in Article IV hereof, as applicable to such creditor.”

2.            The first of sentence of Section 9.1 of the Agreement is hereby deleted in its entirety and replaced with the following:

“Unless otherwise mutually agreed in writing between the Purchaser and the Shareholders, the Closing shall take place at the offices of Blank Rome LLP, 1271 Avenue of the Americas, New York, NY 10020, on the date agreed to by the Purchaser and the Shareholders but no later than 8:00 A.M. (Eastern Time) on March 15, 2022.”

3.            Schedule 1.2 of the Agreement is hereby deleted in its entirety and replaced with Schedule 1.2 attached hereto.

4.            All other terms of the Agreement shall remain in full force and effect. The Agreement, as amended by this Amendment, constitutes the entire agreement between the parties with respect to the subject matter thereof.

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5.            This Amendment may be executed in two or more identical counterparts, all of which shall be considered one and the same agreement and shall become effective when counterparts have been signed by each party and delivered to the other party; provided that a facsimile signature shall be considered due execution and shall be binding upon the signatory thereto with the same force and effect as if the signature were an original, not a facsimile signature.

[Signature Page Follows]

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IN WITNESS WHEREOF, the parties have executed this Amendment to the Agreement as of the date first written above.

[Signatures continue on next page]

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Signature page to the Amendment to Share Purchase Agreement

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Schedule 1.2