Hyperion Therapeutics Completes Initial Public Offering and Announces Exercise of Underwriters’ Over-Allotment Option

Hyperion Therapeutics, Inc.Christine Nash, 650-745-7844

Hyperion Therapeutics, Inc. (NASDAQ:HPTX) announced today the completion of its initial public offering of 5,000,000 shares of common stock. In addition, the underwriters of its initial public offering exercised their over-allotment option in full and purchased an additional 750,000 shares of common stock. All of such shares were sold by Hyperion Therapeutics at the initial public offering price of $10.00 per share. Leerink Swann LLC and Cowen and Company, LLC acted as joint book-running managers for the proposed offering, and Needham & Company, LLC acted as co-manager of the offering.

A registration statement relating to these securities was declared effective by the Securities and Exchange Commission on July 25, 2012. The offering was made only by means of a prospectus, copies of which may be obtained from Leerink Swann LLC, Attention: Syndicate Department, One Federal Street, 37th Floor, Boston, MA 02110, by calling (800) 808-7525, and Cowen and Company, LLC, c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, NY 11717, Attn: Prospectus Department, by calling (631) 274-2806, or faxing (631) 254-7140.

This press release shall not constitute an offer to sell or the solicitation of an offer to buy, nor shall there be any sale of these securities in any state or other jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or other jurisdiction.

Hyperion Therapeutics is a biopharmaceutical company focused on the development and commercialization of novel therapeutics to treat disorders in the areas of orphan diseases and hepatology. Hyperion Therapeutics is developing Ravicti™ (glycerol phenylbutyrate) for two orphan indications: urea cycle disorders and hepatic encephalopathy.