Immedica Pharma US Inc, an affiliate of Swedish pharmaceutical company Immedica Pharma AB, announced on Monday that it has received accelerated approval from the US Food and Drug Administration (FDA) for Loargys (pegzilarginase-nbln), an arginine specific enzyme indicated for the treatment of hyperargininemia in adults and paediatric patients two years of age and older with Arginase 1 Deficiency (ARG1-D), in conjunction with dietary protein restriction.

This indication is approved under accelerated approval based on reduction of plasma arginine. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial.

According to Immedica, LOARGYS is the first and only treatment to address persistently elevated levels of plasma arginine, the primary driver of ARG1-D. It is expected to be available in the United States in April 2026.

Dr. Stephen Cederbaum, professor Emeritus of Human and Medical Genetics at UCLA, said: "Until now, the care of patients with Arginase 1 Deficiency has been limited to symptomatic management and strict dietary control. The accelerated approval of LOARGYS offers a fundamentally new approach that addresses the enzyme deficiency itself. Since persistently elevated arginine and its metabolites have been reported to be the proximal or direct driver of disease progression, this is a major advancement in metabolic medicine."