sodium phenylbutyrate

Sodium phenylbutyrate is a small molecule nitrogen-scavenging agent used as adjunctive therapy for the chronic management of patients with urea cycle disorders (UCDs). It is a prodrug that is rapidly metabolized in the body to phenylacetate. Phenylacetate then undergoes enzymatic conjugation with glutamine in the liver and kidneys to form phenylacetylglutamine, which is subsequently excreted by the kidneys. This metabolic pathway provides an alternative vehicle for nitrogen excretion, bypassing defective steps in the urea cycle (such as deficiencies in CPS, OTC, or AS enzymes) and helping to prevent the accumulation of toxic ammonia. Originally developed by Ucyclyd Pharma and later acquired by Hyperion Therapeutics and Horizon Therapeutics, the drug is now part of the Amgen portfolio following its acquisition of Horizon in 2023. It is typically administered orally in tablet or powder form.

Brand names

BuphenylPheburane

Other names

Sodium 4-phenylbutyrateSodium4-phenylbutyrateSodium-4-phenylbutyrate4-phenylbutyric acid sodium salt