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): November 9, 2015

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))

Item 8.01                                           Other Events.

On November 9, 2015, Supernus Pharmaceuticals, Inc. (the “Company”) issued a press release announcing that the Company’s management will present an overview and update of the Company and host investor meetings at investor conferences in New York City on November 17, 2015 and December 1, 2015.  A copy of this press release is furnished as Exhibit 99.1 hereto and is incorporated herein by reference.

Item 9.01                                           Financial Statements and Exhibits.

(d)                                 Exhibit

The following document is furnished as an Exhibit pursuant to Item 8.01 hereof:

Exhibit 99.1 — Press Release Dated November 9, 2015.

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SIGNATURES

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.

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EXHIBIT INDEX

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Exhibit 99.1

Supernus to Present at Two Investor Conferences

ROCKVILLE, Md., November 9, 2015 — Supernus Pharmaceuticals, Inc. (NASDAQ: SUPN), a specialty pharmaceutical company focused on developing and commercializing products for the treatment of central nervous system diseases, today announced that the Company’s management will present an overview and update of the Company and host investor meetings at the following investor conferences:

Stifel 2015 Healthcare Conference

Presentation Date: Tuesday, November 17th
Presentation Time: 4:30 PM ET
Place: The New York Palace Hotel, New York

Piper Jaffray 27th Annual Healthcare Conference

Presentation Date: Tuesday, December 1st

Presentation Time: 10:30 AM ET

Place:  The New York Palace Hotel, New York

Investors interested in arranging a meeting with the Company’s management during these conferences should contact the respective conference coordinator.

A live webcast of the presentations can be accessed by visiting ‘Events & Presentations’ in the Investors Section on the Company’s website at www.supernus.com. An archived replay of each webcast will be available for 60 days on the Company’s website following the conferences.

About Supernus Pharmaceuticals, Inc.

Supernus Pharmaceuticals, Inc. is a specialty pharmaceutical company focused on developing and commercializing products for the treatment of central nervous system diseases. The Company has two marketed products for epilepsy, Oxtellar XR® (extended-release oxcarbazepine) and Trokendi XR® (extended-release topiramate). The Company is also developing several product candidates to address large market opportunities in psychiatry, including SPN-810 for the treatment of impulsive aggression in patients with ADHD in conjunction with standard ADHD treatment, and SPN-812 for ADHD.

CONTACT:

Jack A. Khattar, President and CEO

Gregory S. Patrick, Vice President and CFO

Supernus Pharmaceuticals, Inc.

Tel: (301) 838-2591

Or

Investor Contact:

Peter Vozzo

Westwicke Partners

Office: (443) 213-0505

Mobile: (443) 377-4767

Email: peter.vozzo@westwicke.com