Acer Therapeutics (NASDAQ: ACER) and Relief Therapeutics (OTCQB: RLFTF) have reported that the FDA has approved OLPRUVA (sodium phenylbutyrate) for oral suspension in the United States to treat certain patients living with urea cycle disorders (UCDs) involving deficiencies of carbamylphosphate synthetase (CPS), ornithine transcarbamylase (OTC), or argininosuccinic acid synthetase (AS).

UCDs are a group of rare, genetic disorders that can cause harmful ammonia to build up in the blood, potentially resulting in brain damage and neurocognitive impairments if ammonia levels are not controlled.

OLPRUVA's approval triggers the availability of a $42.5 million term loan to Acer under a previously announced March 2022 loan agreement that the company entered into with affiliates of Marathon Asset Management L.P.

OLPRUVA received FDA approval under section 505(b)(2) of the Federal Food, Drug, and Cosmetic Act (FDCA), a regulatory pathway that allows applicants to rely, at least in part, on third party data for approval.

In its New Drug Application (NDA), Acer cited preclinical and clinical safety and efficacy data from the reference listed drug (RLD), BUPHENYL powder, which is approved as adjunctive therapy in the chronic management of patients with UCDs involving deficiencies of CPS, OTC, or AS.

The company also provided additional data, including studies that evaluated the bioavailability and bioequivalence of OLPRUVA compared to BUPHENYL powder. The data from these studies, presented at the Society for Inherited Metabolic Disorders (SIMD) Annual Meeting in April 2022 and the Genetic Metabolic Dieticians International (GMDI) Conference in May 2022, showed that OLPRUVA was bioequivalent to BUPHENYL powder.

“The daily challenges of living with a UCD can be overwhelming and emotionally draining for patients and their families,” said Tresa Warner, president of the National Urea Cycle Disorders Foundation. “We welcome new treatment options that can help patients, caregivers and their healthcare teams manage UCDs.”

OLPRUVA is a prescription medicine used alongside certain therapies, including changes in diet, for the long-term management of adults and children weighing 44 pounds (20 kg) or greater and with a body surface area (BSA) of 1.2 m2 or greater, with UCDs involving deficiencies of CPS, OTC, or AS. OLPRUVA is not used to treat rapid increases in ammonia in the blood (acute hyperammonemia), which can be life-threatening and requires emergency medical treatment.

Shares of Acer Therapeutics trade on the NASDAQ under the ticker symbol ACER while Relief Therapeutics trade on the OTC under RLFTF. For more information visit www.acertx.com.