Exhibit 32.1

CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Annual Report on Form 10-K of Blueprint Medicines Corporation (the “Company”) for the year ended December 31, 2024 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), each of the undersigned officers of the Company hereby certifies, pursuant to 18 U.S.C. Section 1350, that to his knowledge:

(1)

the Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (15 U.S.C. 78m or 78o(d)); and

(2)

the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: February 13, 2025	By:	/s/ Kathryn Haviland
		Kathryn Haviland
		President and Chief Executive Officer
		(Principal Executive Officer)

Date: February 13, 2025	By:	/s/ Michael Landsittel
		Michael Landsittel
		Chief Financial Officer
		(Principal Financial Officer)