Horizon Pharma, Inc. Announces Receipt of Additional U.S. Patent Allowance for DUEXIS®

DEERFIELD, IL--(Marketwire - February 05, 2013) - Horizon Pharma, Inc. (NASDAQ: HZNP) today announced that it has received a Notice of Allowance from the United States Patent and Trademark Office (USPTO) for U.S. Patent Application Serial No. 13/620,150 entitled "Stable Compositions of Famotidine and Ibuprofen" with claims that cover DUEXIS® (ibuprofen and famotidine) tablets. DUEXIS is indicated for the relief of signs and symptoms of rheumatoid arthritis and osteoarthritis and to decrease the risk of developing upper gastrointestinal ulcers.

"This additional Notice of Allowance for DUEXIS, our fourth in the U.S., continues to validate the strength of our intellectual property for DUEXIS," said Timothy P. Walbert, chairman, president and chief executive officer, Horizon Pharma. "Horizon will continue to vigorously expand and protect the innovation and intellectual property of DUEXIS, with protection currently out to 2028."

The Notice of Allowance concludes the substantive examination of this U.S. patent application and will result in the issuance of the U.S. patent after administrative processes are completed. The U.S. patent scheduled to issue from this application will expire in 2028. After issuance, Horizon plans to list the U.S. patent in the FDA's Approved Drug Products with Therapeutic Equivalence Evaluations, or Orange Book. Horizon has now been granted four patents covering DUEXIS in the U.S. since October 2011.

About DUEXIS
DUEXIS, a proprietary single-tablet combination of the NSAID ibuprofen and the histamine H2-receptor antagonist famotidine, is indicated for the relief of signs and symptoms of rheumatoid arthritis and osteoarthritis and to decrease the risk of developing upper gastrointestinal ulcers, which in the clinical trials was defined as a gastric and/or duodenal ulcer, in patients who are taking ibuprofen for those indications. The clinical trials primarily enrolled patients less than 65 years of age without a prior history of gastrointestinal ulcer. Controlled trials do not extend beyond 6 months. For more information, please visit www.DUEXIS.com.

Important Safety Information About DUEXIS
DUEXIS is not right for everyone. People who have had asthma, hives, or an allergic reaction to aspirin or other NSAIDs should not take DUEXIS. Women in the late stages of pregnancy should not take DUEXIS. People who have had allergic reactions to medications like famotidine (histamine H2-receptor antagonists) should not take DUEXIS.

Tell your health care provider right away if you have signs of active bleeding (persistent and unexplained) while you are taking DUEXIS.

NSAID-containing medications like DUEXIS can cause high blood pressure or make existing high blood pressure worse, either of which can increase the chance of a heart attack or stroke. Your health care provider should check your blood pressure while you are taking DUEXIS.

Before you start taking DUEXIS, tell your health care provider if you have heart problems, kidney problems, or liver problems, or if you are taking medications for high blood pressure. DUEXIS can increase the chance of potentially significant liver injury and/or kidney injury, which may be fatal. Stop taking DUEXIS immediately and contact your health care provider if you experience any signs and/or symptoms of liver or kidney injury.

Serious allergic reactions, including skin reactions, can happen without warning and can be life threatening. Stop taking DUEXIS and consult your doctor immediately if you get a skin rash or if you start to have problems breathing or swallowing or if you develop swelling of your face or throat.

The most common side effects of DUEXIS include nausea, diarrhea, constipation, upper abdominal pain and headache.

Please see Medication Guide and full Prescribing Information, available at www.DUEXIS.com.

About Horizon Pharma
Horizon Pharma, Inc. is a specialty pharmaceutical company that has developed and is commercializing DUEXIS and RAYOS/LODOTRA, both of which target unmet therapeutic needs in arthritis, pain and inflammatory diseases. The Company's strategy is to develop, acquire, in-license and/or co-promote additional innovative medicines where it can execute a targeted commercial approach in specific therapeutic areas while taking advantage of its commercial strengths and the infrastructure the Company has put in place.

Forward-Looking Statements
This press release contains forward-looking statements, including statements regarding the issuance of a patent based on the notice of allowance from the U.S. Patent and Trademark Office and the ability to protect the commercial potential of DUEXIS to 2028. These forward-looking statements are based on management's expectations and assumptions as of the date of this press release, and actual results may differ materially from those in these forward-looking statements as a result of various factors. These factors include risks regarding whether the administrative processes required for the issuance of a patent as indicated in the notice of allowance will be completed in a timely matter or at all, whether the patent, if issued as indicated in the notice of allowance, will provide sufficient protection and market exclusivity for DUEXIS, whether any patents issued to Horizon may be challenged, invalidated, infringed or circumvented by third parties and other factors described in Horizon's filings with the United States Securities and Exchange Commission, including those factors discussed under the caption "Risk Factors" in those filings. Forward-looking statements speak only as of the date of this press release, and Horizon undertakes no obligation to update or revise these statements, except as may be required by law.