EXHIBIT 32.1

SUPERNUS PHARMACEUTICALS, INC.

CERTIFICATION PURSUANT TO

18 U.S.C. sec. 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report of Supernus Pharmaceuticals, Inc. (the “Company”) on Form 10-Q for the period ended June 30, 2022 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Jack A. Khattar, President and Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. sec. 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

(1)The Report fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934; 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: August 8, 2022	By:	/s/ Jack A. Khattar
		Jack A. Khattar President and Chief Executive Officer