Milestone Pharmaceuticals Inc.

**UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of

the Securities Exchange Act of 1934

Filed by the Registrant☒

Filed by a Party other than the Registrant☐

Check the appropriate box:

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

April 30, 2026

Dear Fellow Shareholders:

On behalf of the Board of Directors of Milestone Pharmaceuticals Inc. (the “Company” or “Milestone”), I want to take this opportunity to invite you to attend our 2026 Annual Meeting of Shareholders (the “Annual Meeting”). The Annual Meeting will be held at 11:00 a.m., Eastern Time, on Wednesday, June 10, 2026. During the Annual Meeting, registered shareholders and duly appointed proxyholders will vote on the proposals set forth in the Notice of Annual Meeting and the accompanying management proxy circular and proxy statement (the “Proxy Statement”), as well as receive a report on the progress of the Company. For those shareholders who have previously provided instructions to receive paper copies of our proxy materials, a paper copy will be sent to you in addition to a Notice Regarding Internet Availability of Proxy Materials (the “Notice”). The Annual Meeting will take place via a virtual meeting portal through which you can listen to the Annual Meeting, submit questions and vote online. You will not be able to attend the Annual Meeting in person.

We are providing access to our proxy materials, including our Annual Report on Form 10-K for the fiscal year ended December 31, 2025, in a fast and efficient manner via the Internet to all shareholders of record as of April 15, 2026, and will post our proxy materials on the website referenced in the Notice (www.envisionreports.com/milestone2026). As more fully described in the Notice, all shareholders may choose to access our proxy materials on the website referred to in the Notice or may request to receive a printed set of our proxy materials. In addition, the Notice and website will provide information regarding how you may request to receive proxy materials in printed form by mail or electronically by email on an ongoing basis.

Your vote at the Annual Meeting is important. Whether or not you plan to attend the Annual Meeting, we hope you will vote as soon as possible. You will find voting instructions in the Notice, the Proxy Statement and on the Proxy Card. You may vote prior to the Annual Meeting, via the Internet, by telephone or by mail, or at the Annual Meeting via the online virtual meeting platform. Alternatively, if you requested a printed copy of the proxy materials by mail, or if we elect to subsequently send you a paper Proxy Card, you may mark, date, sign and mail the Proxy Card in the envelope provided.

We appreciate your continued ownership of Milestone shares and your support.

Sincerely,

/s/ Joseph Oliveto

Joseph Oliveto

President and Chief Executive Officer

**MILESTONE PHARMACEUTICALS INC.

1111 Dr. Frederik-Philips Boulevard, Suite 420,

Montréal, Québec, Canada H4M 2X6

NOTICE OF ANNUAL MEETING OF SHAREHOLDERS

JUNE 10, 2026

To the Shareholders of Milestone Pharmaceuticals Inc.:

NOTICE IS HEREBY GIVEN that the 2026 Annual Meeting of Shareholders (the “Annual Meeting”) of Milestone Pharmaceuticals Inc., a corporation existing under the laws of the province of Québec (the “Company” or “Milestone”), will be held on Wednesday, June 10, 2026, at 11:00 a.m., Eastern Time. The Meeting will take place via a virtual meeting portal through which registered shareholders and duly appointed proxyholders can listen to the Annual Meeting, submit questions and vote online. The Annual Meeting can be accessed by visiting https://meetnow.global/MUAPKKN. The Annual Meeting is being held virtually to enable greater participation by shareholders, and all shareholders, regardless of geographic location and equity ownership, will have an equal opportunity to participate. You will not be able to attend the Annual Meeting in person.

The purpose of the Annual Meeting will be the following:

The record date for the Annual Meeting is April 15, 2026 (the “Record Date”). Only registered shareholders at the close of business on the Record Date will be entitled to notice of and to vote during the Annual Meeting via the virtual meeting platform or by proxy.

We are providing access to our proxy materials, including our Annual Report on Form 10-K for the fiscal year ended December 31, 2025, to all shareholders of record as of the Record Date, in a fast and efficient manner via the Internet. On or around April 30, 2026, we will begin mailing a Notice Regarding Internet Availability of Proxy Materials (the “Notice”), to all shareholders of record as of the Record Date and post our proxy materials on the website referenced in the Notice (www.envisionreports.com/milestone2026). As more fully described in the Notice, all shareholders may choose to access our proxy materials free of charge on the website referred to in the Notice or may request to receive a printed set of our proxy materials free of charge. These materials will remain available on the website through the conclusion of the Annual Meeting. In addition, the Notice and website provide information regarding how you may request to receive proxy materials in printed form by mail or electronically by email on an ongoing basis. For those shareholders who have previously provided instructions to receive paper copies of our proxy materials, a paper copy will be sent to you in addition to the Notice. The management proxy circular and proxy statement (the “Proxy Statement”) that accompanies this Notice of Annual Meeting of Shareholders contains additional information regarding the proposals to be considered at the Annual Meeting, and shareholders are encouraged to read it in its entirety.

Shareholders are invited to attend the Annual Meeting via our virtual meeting platform and are urged to vote on the matters before the Annual Meeting by proxy (whether by mail, phone or the Internet). Registered shareholders who are unable to attend the Annual Meeting via our virtual meeting platform are requested to vote via the Internet prior to the Annual Meeting, by going to www.investorvote.com and following the instructions on the website, or vote by calling toll free 1-866-732-8683 on a touch tone telephone and following the instructions provided by “Vote Voice.” You will need to refer to the Proxy Card and to your 15-digit control number provided on the Notice or Proxy Card. Alternatively, if you received a printed copy of the proxy materials by mail, or if we subsequently elect to send you a paper Proxy Card, you may vote by mail by completing, dating and signing the Proxy Card and sending it to Computershare Investor Services Inc., 320 Bay Street, 14th Floor, Toronto Ontario M5H 4A6.

Beneficial owners of shares held through a broker, bank, or other agent, should have received a voting instruction form with these proxy materials from that organization rather than from Milestone. Beneficial owners should simply complete and mail the voting instruction form in accordance with the instructions in that form to ensure that their vote is counted. Alternatively, they may vote by telephone or over the Internet by following the instructions provided by their broker, bank or other nominee if such alternative is provided. Beneficial owners should provide their voting instructions to their broker, bank or nominee sufficiently in advance of the Annual Meeting to enable their broker, bank or nominee to act upon them and in accordance with the instructions provided by their broker, bank, or other agent.

For your vote to be effective, your voting instructions must be received by Computershare Investor Services Inc. (“Computershare”) not later than5:00 p.m. (Eastern Time) on Monday, June 8, 2026, or, in the case of any adjournment of the Annual Meeting, not less than 48 hours, excluding Saturdays, Sundays and applicable holidays, prior to the time of the rescheduled meeting. The Board may, at its discretion, accept late proxies or waive the time limit for deposit of proxies, but is under no obligation to accept or reject any late proxy.If you have voted by proxy using the Proxy Card, via fax or the Internet prior to the Annual Meeting or by telephone, any subsequent vote by proxy through any of these methods will cancel any other proxy you may have previously submitted in connection with the Annual Meeting, and only the latest dated proxy received prior to the deadline will be counted.

By Order of the Board of Directors,

/s/ Amit Hasija

Amit Hasija

Chief Financial Officer and Executive Vice President of Corporate Development

Dated: April 30, 2026

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**1111 Dr. Frederik-Philips Boulevard, Suite 420

Montréal, Québec, Canada H4M 2X6