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): February 08, 2016

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 February 08, 2016, Supernus Pharmaceuticals, Inc. (the “Company”) issued a press release announcing that following a seven-day bench trial, Judge Renee Marie Bumb of the United States District Court for the District of New Jersey ruled that Actavis Inc. and its subsidiaries infringed U.S. Patent Nos. 7,722,898, and 7,910,131 by submitting to the FDA an ANDA seeking permission to market a generic version of Oxtellar XR® before the expiration of the Company’s patents. Judge Bumb also ruled that U.S. Patent Nos. 7,722,898, 7,910,131, and 8,617,600 are valid. The FDA’s Orange Book lists all three patents as expiring on April 13, 2027.

In addition to the above three patents that are subject to the Federal Court decision, Oxtellar XR is further protected by two other patents that are also listed in the Orange Book and that have an expiration that is no earlier than 2027. Finally, as of the date of the press release, the Company is not aware of any FDA approval for the Actavis ANDA. 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 February 08, 2016.

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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 Prevails in Oxtellar XR® ANDA Litigation

A Federal Court finds Supernus patents valid and Actavis infringing two of them

ROCKVILLE, Md., February 8, 2016 — 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 following a seven-day bench trial, Judge Renee Marie Bumb of the United States District Court for the District of New Jersey ruled that Actavis Inc. and its subsidiaries infringed U.S. Patent Nos. 7,722,898 and 7,910,131 by submitting to the FDA an ANDA seeking permission to market a generic version of Oxtellar XR® before the expiration of Supernus’ patents.  Judge Bumb also ruled that U.S. Patent Nos. 7,722,898, 7,910,131, and 8,617,600 are valid.  The FDA’s Orange Book lists all three patents as expiring on April 13, 2027.

“We are pleased with the court’s ruling that Actavis will infringe two of our patents on Oxtellar XR, and the finding that all three patents are valid,” stated Jack Khattar, President and Chief Executive Officer of Supernus Pharmaceuticals. “We will continue to vigorously defend our novel products and build upon our strong intellectual property to provide our products the protection they are entitled to.”

In addition to the above three patents that were subject to the Federal Court decision, Oxtellar XR is further protected by two other patents that are also listed in the Orange Book and that have an expiration date that is no earlier than 2027. Finally, as of the date of this press release, we are not aware of any FDA approval for the Actavis ANDA.

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.

Forward Looking Statements

This press release contains forward-looking statements regarding the Company’s ability to defend and enforce its intellectual property rights covering Oxtellar XR or Trokendi XR. Actual results may differ materially from those in these forward-looking statements as a result of various factors, including, but not limited to, the ability of Supernus to finance potential litigation and to prevail in any such proceeding to successfully defend its intellectual property rights. For a further description of these and other risks facing the Company, please see the risk factors described in the Company’s Annual Report Form 10-K that was filed with the United States Securities and Exchange Commission (“Commission”) on March 12, 2015 under the caption “Risk Factors” and the updates to these risk factors in the Company’s

Quarterly Report form 10-Q filed with the Commission on November 9, 2015. Forward-looking statements speak only as of the date of this press release, and the Company undertakes no obligation to update or revise these statements, except as may be required by law.

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