UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): May 15, 2018

Supernus Pharmaceuticals, Inc.

(Exact name of registrant as specified in its charter)

Delaware

(State or other jurisdiction of
Incorporation)

Registrant’s telephone number, including area code:  (301) 838-2500

Not Applicable

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). o

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

Item 5.02                                           Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

(b)  On May 15, 2018, Victor Vaughn, Senior Vice President, Sales and Marketing, notified Supernus Pharmaceuticals, Inc. (“Supernus” or the “Company”) of his retirement from the Company effective May 31, 2018 to spend more time with his family. Mr. Vaughn has been commuting from Kentucky for several years since he joined Supernus as a full time employee and prior to that on a consulting basis.

Supernus very much appreciates all the significant contributions Mr. Vaughn has made to the Company and fully understands his desire to retire and be back with his family. Mr. Vaughn’s direct reports, Todd Horich, Vice President of Marketing, and Taylor Raiford, Vice President of Sales, will report directly to the CEO of the Company. Messrs. Horich and Raiford have been leading the commercial organization in their respective areas since the Company built its commercial infrastructure. Messrs. Horich and Raiford joined the Company in 2010 and 2012, respectively, built their respective teams and led them through the successful launch of Oxtellar XR and Trokendi XR.

2

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

3