Hyperion Therapeutics Announces Health Canada Accepts RAVICTI(R) New Drug Submission With Priority Review

BRISBANE, Calif., June 3, 2014 (GLOBE NEWSWIRE) -- Hyperion Therapeutics, Inc. (Nasdaq:HPTX) today announced that the validation period is complete for its New Drug Submission (NDS) to Health Canada for RAVICTI (glycerol phenylbutyrate) Oral Liquid for the treatment of urea cycle disorders (UCDs), and that the RAVICTI NDS was granted Priority Review. Standard review in Canada takes 18 months or more and Priority Review, which is granted to promising medicines that address life-threatening or severely debilitating conditions, shortens the review time to approximately six months.

"We are pleased with the acceptance of the NDS with Priority Review for RAVICTI and potentially expanding the availability of RAVICTI to UCD patients outside of the United States," said Donald J. Santel, president and chief executive officer of Hyperion. "If approved, RAVICTI will be the first treatment approved by Health Canada to treat UCDs."

The NDS is based on results from 10 controlled and uncontrolled clinical trials studying the safety and efficacy of RAVICTI in 359 patients across three populations, including 114 UCD patients. Data from multiple Canadian patients enrolled at the University of Toronto were included in the submission. The safety and efficacy of RAVICTI is under review by Health Canada and market authorization has not yet been granted.

UCD patients lack enzymes or transporters necessary for the conversion of ammonia to urea and experience heightened levels of ammonia in the bloodstream. Left untreated, UCDs can result in neurological damage, coma, and/or death. Approved by the Food and Drug Administration on February 1, 2013, RAVICTI is an odorless nearly tasteless liquid medication used for the long-term management of high blood levels of ammonia. In short term clinical studies involving more than 80 UCD patients ages two years and older, RAVICTI was safe and efficacious based on 24-hour ammonia profiles. In addition in long-term follow up studies, patients on RAVICTI maintained average fasting ammonia levels below the upper limit of normal. What makes RAVICTI different from other currently available ammonia removing medicines is that it requires digestion such that the active ingredient enters the circulation more slowly.

RAVICTI Safety Information

RAVICTI is indicated for use as a nitrogen-binding agent for chronic management of adult and pediatric patients ≥2 years of age with UCDs who cannot be managed by dietary protein restriction and/or amino acid supplementation alone. RAVICTI must be used with dietary protein restriction and, in some cases, dietary supplements (e.g., essential amino acids, arginine, citrulline, protein-free calorie supplements). RAVICTI is not indicated for the treatment of acute hyperammonemia in patients with UCDs because more rapidly acting interventions are essential to reduce plasma ammonia levels. The safety and efficacy of RAVICTI for the treatment of N-acetylglutamate synthase (NAGS) deficiency has not been established. The use of RAVICTI in patients less than 2 months of age is contraindicated.

For additional Important Safety Information, including Warnings and Precautions, Adverse Events, Drug Interactions, and Special Populations, please see full Prescribing Information ( http://www.ravicti.com/files/RAVICTI_Prescribing_Information.pdf) and Medication Guide ( http://www.ravicti.com/files/RAVICTI_Medication_Guide.pdf) for RAVICTI.

About Hyperion Therapeutics

Hyperion Therapeutics, Inc. is a commercial stage biopharmaceutical company committed to developing and delivering life-changing treatments for orphan diseases. The company's first commercial product, RAVICTI® (glycerol phenylbutyrate) Oral Liquid, was approved in February 2013 and is currently being marketed in the United States. The company also owns worldwide rights to BUPHENYL® (sodium phenylbutyrate) Tablets and Powder, which it markets in the U.S. The compound is also marketed internationally through business partners. In addition, the company is developing glycerol phenylbutyrate for the potential treatment of hepatic encephalopathy. Upon closing of the recently announced acquisition of Andromeda Biotech Ltd., the company will also own DiaPep277 ®, a first-in-class immune intervention therapy for new onset Type 1 diabetes. The company expects to close the Andromeda acquisition during second quarter 2014. For more information, please visit www.hyperiontx.com.
CONTACT: Myesha Edwards         Corporate Communications and Investor Relations         (650) 745-7829