Milestone Pharmaceuticals Inc.

Exhibit 99.1

Milestone Pharmaceuticals Submits Response to the FDA’s CRL for CARDAMYST (etripamil) Nasal Spray for PSVT Following Type A Meeting

Montreal and Charlotte, N.C., June 16, 2025 -- Milestone® Pharmaceuticals Inc. (Nasdaq: MIST) today announced submission of its response to the U.S. Food and Drug Administration (FDA)’s Complete Response Letter (CRL) regarding its New Drug Application (NDA) for CARDAMYST™ (etripamil) nasal spray, a prescription medication in development for the conversion of acute episodes of paroxysmal supraventricular tachycardia (PSVT) to sinus rhythm in adults. The response follows a Type A meeting recently held with the FDA. The acceptance of the response and corresponding Prescription Drug User Fee Act (PDUFA) date will be determined within the next thirty days per FDA policy. The review time is expected to be within 2 or 6 months from the resubmission, depending on the classification.

“Our recent Type A meeting with the FDA was productive and we believe it provided the guidance necessary to submit our response to the CRLdirectly after the meeting,” said Joe Oliveto, President and Chief Executive Officer of Milestone Pharmaceuticals. “We appreciate the engagement with the FDA and are excited to prepare for a potential new PDUFA date this year. We continue to believe in the value of CARDAMYST which, if approved, will be the first and only self-administered therapy for the rapid termination of episodes of PSVT.”