Pegzilarginase is currently being evaluated in a Phase 3 trial for the treatment of Arginase 1 Deficiency.

Our most advanced investigational medicine is pegzilarginase, a novel, recombinant human arginase 1 enzyme designed to lower levels of the amino acid arginine. An elevated level of arginine is the hallmark of Arginase 1 Deficiency (ARG1-D), a debilitating, progressive, inherited metabolic disease that typically presents in childhood. Patients with ARG1-D experience persistently high levels of arginine, which leads to muscle tightness (spasticity), missed developmental milestones, intellectual disability, seizures and early death.

In data from a Phase 1/2 clinical trial and its open-label extension study, treatment with pegzilarginase was shown to rapidly and sustainably reduce blood arginine levels in patients with ARG1-D. The data also showed that pegzilarginase improved clinical outcomes, including mobility and motor function. Pegzilarginase was well tolerated, with most treatment-related adverse events being mild and manageable with standard measures.

Pegzilarginase is investigational. Safety and efficacy have not been established by any agency.

In a clinical trial, pegzilarginase demonstrated rapid and sustainable reduction in arginine to goal levels in people with ARG1-D.

Pegzilarginase is currently being investigated in a global, placebo-controlled, pivotal Phase 3 trial, called PEACE, which is designed to assess the effects of treatment with pegzilarginase over 24 weeks. For more information on the ongoing studies of pegzilarginase, please visit the Clinical Trials page.

Pegzilarginase has received several regulatory designations, including Fast Track, Breakthrough, Orphan Drug and Rare Pediatric Disease Designations from the U.S. Food and Drug Administration as well as Orphan Drug Designation from the European Medicines Agency.

Advancing Multiple Development Programs