South San Francisco, CA - November 12, 2008 - Hyperion Therapeutics, Inc. today reported completion of data analysis for its Phase 2 clinical trial designed to evaluate the safety, tolerability and ammonia scavenging effects of HPN-100 versus BUPHENYL® (sodium phenylbutyrate), the current standard of care in patients with urea cycle disorders. Data from the trial will be presented at an upcoming medical conference.
“We are encouraged by this trial and the potential to develop a new therapy for patients with urea cycle disorders,” said Dr. Bruce Scharschmidt, Senior Vice President and Chief Medical Officer of Hyperion Therapeutics, Inc. “Based on the results, we plan to meet with the Food and Drug Administration in early 2009 to discuss our Phase 3 development program.”
“We are pleased with the progress of the HPN-100 clinical program,” said Cindy LeMons, Executive Director of the National Urea Cycle Disorders Foundation (NUCDF). “The urea cycle disorder community encourages the development of treatment alternatives.”
Hyperion and Ucyclyd Pharma, Inc., a subsidiary of Medicis Pharmaceutical Corporation, entered into a collaboration agreement for HPN-100 in August 2007. Under the terms of the agreement, Hyperion is conducting ongoing research and development of HPN-100 for urea cycle disorders, hepatic encephalopathy, and other forms of hyperammonemia.
About Urea Cycle Disorder
Urea cycle disorders are inherited, inborn errors of metabolism present in an estimated 1 in 10,000 births in the United States. Patients with urea cycle disorders are deficient in one of the key enzymes that comprise the urea cycle, the body’s primary vehicle for removing ammonia, a potent neurotoxin, from the bloodstream. Onset may occur at any age depending on the severity of the disorder. Left untreated, urea cycle disorders can cause dangerously heightened levels of ammonia in the bloodstream (hyperammonemia) resulting in brain damage, coma, and/or death.
HPN-100 is a pro-drug of phenylbutyrate and a pre-pro-drug of phenylacetic acid, the active moiety of BUPHENYL®, the only therapy currently FDA-approved as adjunctive therapy for the chronic management of patients with the most prevalent urea cycle deficiencies including those related to carbamylphosphate synthetase, ornithine transcarbamylase and argininosuccinic acid synthetase. HPN-100, which is dosed orally in liquid form, provides an alternative pathway to the urea cycle for the disposal of waste nitrogen through the renal excretion of phenylacetylglutamine, which is formed from phenylacetic acid and glutamine.
BUPHENYL® is indicated as adjunctive therapy in the chronic management of patients with urea cycle disorders involving deficiencies of carbamylphosphate synthetase (CPS), ornithine transcarbamylase (OTC), or argininosuccinic acid synthetase (AS). BUPHENYL® should not be administered to patients with known hypersensitivity to sodium phenylbutyrate or any component of this preparation. The most common adverse reactions associated with BUPHENYL® were amenorrhea dysfunction, decreased appetite, body odor (probably caused by its metabolite phenylacetate) and bad taste or taste aversion. Patients with urea cycle disorders should not take valproic acid, haloperidol, or steroids as these drugs have been reported to increase blood ammonia levels, and probenecid may affect the kidneys’ excretion. Use with great care, if at all, in patients with congestive heart failure or severe renal insufficiency, and in clinical states where there is sodium retention with edema. Use caution when administering to patients with hepatic or renal insufficiency or inborn errors of beta oxidation. The safety or efficacy of doses in excess of 20 grams (40 tablets) per day has not been established.
The National Urea Cycle Disorders Foundation is a nationally-recognized nonprofit organization dedicated to saving children and adults from the catastrophic effects of urea cycle disorders. The Foundation is a lifeline to families and medical professionals all over the world desperately seeking crisis intervention and treatment information. The Foundation’s mission is to provide information, guidance and support to patients and their families, to educate healthcare professionals on the identification, diagnosis and treatment of UCDs, to raise awareness so that no child or adult ever goes undiagnosed, and to stimulate and support critical research activities and a CURE. The Foundation is headquartered in Pasadena, California. For more information, visit www.nucdf.org, or call (626) 578-0833.
About Hyperion Therapeutics
Hyperion Therapeutics is a privately held specialty therapeutics company focused on the development of therapies that address critical unmet needs and underserved patient populations in the areas of gastroenterology and hepatology. Hyperion is headquartered in South San Francisco, CA. For additional information, visit: www.hyperiontx.com.