NORTHBROOK, IL — (MARKET WIRE) — 09/30/11 — Horizon Pharma, Inc. (NASDAQ: HZNP) today announced the appointments of Michael Grey and Ronald Pauli to the Company’s Board of Directors.

“We are pleased to welcome Mike and Ron to our board. Their extensive pharma and biopharmaceutical experience in business development, finance and building companies will be an asset to our Board and beneficial to Horizon’s future growth,” said Timothy P. Walbert, chairman, president and chief executive officer of Horizon.

Mr. Grey currently serves as president and chief executive officer at Lumena Pharmaceuticals, Inc. During his more than 30-year career in the pharmaceutical and biotechnology industries, Mr. Grey has held senior positions at a number of other companies, including president and chief executive officer of SGX Pharmaceuticals, Inc. (sold to Eli Lilly in 2008), president and chief executive officer of Trega Biosciences, Inc. (sold to Lion Bioscience in 2001) and president of BioChem Therapeutic Inc. Mr. Grey also currently serves as a venture partner at Pappas Ventures. For approximately 20 years, Mr. Grey served in various roles with Glaxo, Inc. and Glaxo Holdings, P.L.C., culminating in his position as vice president, Corporate Development and director, International Licensing. Mr. Grey also serves on the board of directors of BioMarin Pharmaceutical Inc. and Selventa, Inc.

Mr. Grey received a bachelor’s degree in chemistry from the University of Nottingham in the United Kingdom.

Mr. Pauli is currently chief business officer at Sagent Pharmacueticals, Inc., where he was recently promoted from his role as chief financial officer. As CFO, he played a key role in Sagent’s recent initial public offering. In addition, Mr. Pauli has held senior positions at a number of biopharmaceutical companies, including chief financial officer at NeoPharm, Inc. and corporate controller and interim chief financial officer at Abraxis BioScience, Inc., formerly American Pharmaceutical Partners, Inc. Mr. Pauli previously served as corporate controller for Applied Power, Inc. and R.P. Scherer Corporation and also held multiple finance positions at Kmart Corporation.

Mr. Pauli received a bachelor’s degree in accounting from Michigan State University and a master’s degree in finance from Walsh College.

Horizon also announced that Dr. Peter Johann informed the Company he has decided to resign his position from the Horizon Board, effective immediately. Today’s announcements bring the total number of members of the board to eight.

“On behalf of the Board of Directors of Horizon, I would like to thank Peter for his contributions to the Company’s journey to date and we wish him well in his endeavors,” commented Mr. Walbert.

About Horizon Pharma
Horizon Pharma, Inc. is a biopharmaceutical company that is developing and commercializing innovative medicines to target unmet therapeutic needs in arthritis, pain and inflammatory diseases. For more information, please visit www.horizonpharma.com.

Forward-Looking Statements
This press release contains forward-looking statements, including statements regarding potential future contributions of Mr. Grey and Mr. Pauli and future growth of Horizon’s business. 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, but are not limited to, risks regarding Horizon’s ability to obtain regulatory approval for and commercialize products and the effectiveness of Mr. Grey and Mr. Pauli as directors on Horizon’s board. For a further description of these and other risks facing Horizon, please see the risk 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.