The U.S. Food and Drug Administration (FDA) has officially granted accelerated approval to Immedica Pharma’s Loargys (pegzilarginase) for the treatment of Arginase 1 deficiency (ARG1-D). This represents a major turnaround, as the treatment previously received a heavy-handed “refusal-to-file” from regulators in 2022 and a complete response letter (CRL) citing major deficiencies as recently as last August.
Loargys is a recombinant human enzyme designed to replace the deficient natural enzyme, effectively lowering blood arginine levels in patients aged 2 and older. Prior to Loargys, the estimated 250 patients with ARG1-D in the U.S. relied solely on strict protein-restricted diets and symptom management. The approval was supported by additional long-term data demonstrating an 80% reduction in plasma arginine, helping to curb disease progression such as spasticity and intellectual disability.
Immedica expects to make Loargys—which is administered via weekly injections—available in the U.S. by April. This success not only validates Immedica Pharma’s ability to revive promising projects (acquired from Aeglea BioTherapeutics in 2023) but also offers new hope for the global community of patients suffering from ultrarare metabolic disorders.