Hyperion Therapeutics (Hyperion) has reported that its investigational product HPN-100 (glycerol phenylbutyrate) has received orphan product designation from the FDA for intermittent or chronic treatment of patients with cirrhosis and any grade of hepatic encephalopathy.
HPN-100 (glycerol phenylbutyrate) is a pre-pro-drug of phenylacetic acid, the active moiety of Buphenyl, FDA-approved as adjunctive therapy for the chronic management of patients with the most prevalent urea cycle disorders; carbamylphosphate synthetase, ornithine transcarbamylase and argininosuccinic acid synthetase deficiencies.
Glycerol phenylbutyrate is administered orally in liquid form. The company claims, 17.4ml of glycerol phenylbutyrate delivers the same amount of active ingredient as the maximum daily dose of Buphenyl.
Reportedly, the company is planning to initiate a phase II clinical program in the indication later this year.