UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, DC 20549 Form 10-K (Mark One) ☑ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 001-37359 BLUEPRINT MEDICINES CORPORATION (Exact name of registrant as specified in its charter) Delaware 26-3632015 (State or other juris ...