PaxMedica, Inc. Common Stock (PXMD) 8-K Amendments to Articles of Incorporation or Bylaws

Exhibit 3.1

AMENDMENT NO. 1

TO THE AMENDED AND RESTATED BYLAWS OF

PAXMEDICA, INC.

The Amended and Restated Bylaws of PaxMedica, Inc. are hereby amended, effective March 21, 2024, to amend Section 1.6 of Article I:

Section 1.6 Quorum. Except as otherwise provided by law, the Certificate of Incorporation or these Bylaws, the holders of at least 33.4% in voting power of the shares of the capital stock of the Corporation issued and outstanding and entitled to vote at the meeting, present in person, present by means of remote communication in a manner, if any, authorized by the Board in its sole discretion, or represented by proxy, shall constitute a quorum for the transaction of business; provided, however, that where a separate vote by a class or classes or series of capital stock is required by law or the Certificate of Incorporation, the holders of at least 33.4% in voting power of the shares of such class or classes or series of the capital stock of the Corporation issued and outstanding and entitled to vote on such matter, present in person, present by means of remote communication in a manner, if any, authorized by the Board in its sole discretion, or represented by proxy, shall constitute a quorum entitled to take action with respect to the vote on such matter. A quorum, once established at a meeting, shall not be broken by the withdrawal of enough votes to leave less than a quorum.