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 6, 2013

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 2.02                                           Other Events

On May 6, 2013, Supernus issued a press release announcing that it expects to report financial results for the quarter ending March 31, 2013 after the market closes on May 13, 2013, and will hold a conference call and webcast on that date to review the financial results as well as provide an update on other business matters.  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)                                 Exhibits

The following document is furnished as an Exhibit pursuant to Item 2.02 hereof:

Exhibit 99.1 — Press Release dated May 6, 2013 of the Company announcing first quarter 2013 earnings conference call and webcast.

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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

FOR IMMEDIATE RELEASE

Supernus Announces First Quarter 2013 Earnings Conference Call and Webcast

Rockville, MD, May 6, 2013 —Supernus Pharmaceuticals, Inc. (NASDAQ: SUPN), today announced that the Company expects to report financial results for the quarter ended March 31, 2013 after the market closes on Monday May 13, 2013.  Supernus will host a conference call at 5:00 p.m. Eastern Time (2:00 p.m. Pacific Time) to review the financial results, as well as provide an update on other business matters of the Company.

A live webcast will be available at www.supernus.com.  The webcast will be archived on the Company’s website for 30 business days following the live call.

Callers should dial in approximately 10 minutes prior to the start of the call. The phone number to join the conference call is +1(877) 288-1043 (U.S. and Canada) or +1 (970) 315-0267(international and local). The access code for the live call is 59547232.

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, or CNS, diseases. The Company has one marketed product for epilepsy, Oxtellar XR™ (extended-release oxcarbazepine), and one tentatively approved product for epilepsy, Trokendi XR™ (extended-release topiramate). The Company is also developing several product candidates in psychiatry to address large market opportunities in ADHD, including ADHD patients with impulsive aggression. These product candidates include SPN-810 for impulsive aggression in ADHD and SPN-812 for ADHD.

CONTACTS:

Jack Khattar, President and CEO

Gregory S. Patrick, Vice President and CFO

Supernus Pharmaceuticals, Inc.

Tel: (301) 838-2591