Supernus Announces FDA Approval of Its Partner's Product, Orenitram(TM)

Supernus Announces FDA Approval of Its Partner's Product, Orenitram(TM)

ROCKVILLE, Md., Dec. 23, 2013 (GLOBE NEWSWIRE) -- Supernus Pharmaceuticals,
Inc. (Nasdaq:SUPN), a specialty pharmaceutical company, announced today that
the FDA approved Orenitram™ (treprostinil), Extended-Release Tablets for the
treatment of pulmonary arterial hypertension (PAH) in WHO Group I patients to
improve exercise capacity.

Supernus developed the extended release formulation of Orenitram™ under a
Development and License Agreement with United Therapeutics Corporation
(Nasdaq:UTHR). The product uses EnSoTrol, Supernus' novel osmotic technology
platform. Per the license agreement between Supernus and United Therapeutics,
United Therapeutics will pay Supernus certain milestone fees and royalties
associated with the commercialization of the product worldwide.

"This is a very exciting development for Supernus, our partner United
Therapeutics and patients with PAH. This approval is the first of its kind for
an oral prostacyclin analogue for any disease. An orally administered
prostacyclin analogue offers patients and physicians more treatment choices.
We look forward to the launch of the product by United Therapeutics and are
very pleased to be a part of such a novel advancement with our EnSoTrol
technology," said Jack Khattar, Chief Executive Officer, President and
Director of Supernus.

For full patient information and full prescribing information, visit:

http://www.unither.com/assets/unither/docs/OrenitramFullPrescribingInformation.PDF.

Orenitram™ is a trademark of United Therapeutics Corporation.

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 two marketed products for
epilepsy, Oxtellar XR^® (extended-release oxcarbazepine) and 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.

Forward Looking Statements

This press release contains forward-looking statements regarding the potential
for Orenitram™ to treat PAH. Actual results may differ materially from those
in these forward-looking statements as a result of various factors, including,
but not limited to, risks regarding our partner's ability to commercialize the
product successfully, whether physicians will prescribe and patients will use
the product and competition in the market. 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 on March 15, 2013 and under the caption
"Risk Factors" and the updates to these risk factors in the Company's
quarterly report form 10-Q that was filed with the Commission on August 15,
2013. 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 Khattar, President & CEO
         Gregory S. Patrick, Vice President and CFO
         Supernus Pharmaceuticals, Inc.
         Tel: (301) 838-2591