
FORM10-K Indicate by check mark if the registrant is not required to file reports pursuant to Section13 or Section15(d)of the Act. Yes☐No☒ Indicate by check mark whether the registrant (1)has filed all reports required to be filed by Section13 or 15(d)of the Securities Exchange Actof 1934 during the preceding 12months (or for such shorter period that the registrant was required to file such reports), and (2)has been subject to suchfiling requirements for the past 90days. Yes☒No☐ Indicate by check mark whether the registrant has submitted electronically, if any, every Interactive Data File required to be submitted pursuantto Rule405 of RegulationS-T during the preceding 12months (or for such shorter period that the registrant was required to submit and post such files).Yes☒No☐ Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reportingcompany, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer”, “smaller reporting company” and“emerging growth company” in Rule12b-2 of the Exchange Act. If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying withany new or revised financial accounting standards provided pursuant to Section13(a)of the Exchange Act.☐ Indicate by check mark whether the registrant has filed a report on and attestation to its management's assessment of the effectiveness of itsinternal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C 7262(b)) by the registered public accounting firmthat prepared or issued its audit report. Yes☐No☒ Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive‐basedcompensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D‐1(b).☐ As of March 20, 2026, the total number of shares outstanding of the registrant’s Common Shares was 117,667,277 shares, net of treasury shares. DOCUMENTS INCORPORATED BY REFERENCE: Portions of the registrant’s definitive proxy statement for the registrant’s 2025 annual meeting of stockholders, to be filed within 120 days afterthe close of the registrant’s fiscal year, are incorporated by reference into Part III of this Annual Report. Table of Contents TABLE OF CONTENTSSpecial Note Regarding Forward-Looking Statements3Summary of Risk Factors5PART IItem1. Business7Item1A. Risk Factors29Item1B. Unresolved Staff Comments74Item 1C. Cybersecurity75Item2. Properties77Item3. Legal Proceedings77Item4. Mine Safety Disclosures77PART IIItem5. Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchasesof Equity Securities78Item6. Selected Financial Data78Item7. Management’s Discussion and Analysis of Financial Condition and Results of Operations79Item7A. Quantitative and Qualitative Disclosures About Market Risk93Item8. Financial Statements94Item9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure124Item9A. Controls and Procedures124Item9B. Other Information125Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections125PART IIIItem10. Directors, Executive Officers and Corporate Governance126Item11. Executive Compensation126Item12.Security Ownership of Certain Beneficial Owners and Management and RelatedStockholder Matters126Item13. Certain Relationships and Related Transactions, and Director Independence126Item14. Principal Accountant Fees and Services127PART IVItem15. Exhibits and Financial Statement Schedules128Item16. Form 10-K Summary131 “Milestone Pharmaceuticals” and the Milestone logo appearing in this Annual Report on Form10-K areunregistered trademarks of Milestone Pharmaceuticals Inc. All other trademarks, trade names and servicemarks appearing in this Annual Report on Form10-K are the property of their respective owners. Solelyfor convenience, the trademarks and trade names in this Annual Report on Form10-K may be referred towithout the ® and ™ symbols, but such references should not be construed as any indicator that theirrespective owners will not assert their rights thereto. This Annual Report on Form10-K contains references to United States dollars and Canadian dollars. Alldollar amounts referenced, unless otherwise indicated, are expressed in United States dollars. Referencesto “$” are to United States dollars and references to “C$” are to Canadian dollars. SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS This Annual Report on Form10-K contains forward-looking statements about us and our industry thatinvolve substantial risks and uncertainties. All statements other than statements of historical factscontained in this Annual Report on Form10-K, including statements regarding our strategy, futurefinancial condition, future operations, projected costs, prospects, pla