Exhibit 32.1

CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

Pursuant to 18 U.S.C. § 1350, as created by Section 906 of the Sarbanes-Oxley Act of 2002, the undersigned officer of Zenas BioPharma, Inc. (the “Company”) hereby certifies, to the best of my knowledge, that:

(i)

the accompanying Quarterly Report on Form 10-Q of the Company for the fiscal quarter ended June 30, 2025 (the “Report”) fully complies with the requirements of Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934; and

(ii)

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


Dated: August 12, 2025	By:	/s/ Leon O. Moulder, Jr.
		Name:	Leon O. Moulder, Jr.
		Title:	Chief Executive Officer
			(Principal Executive Officer)