Immedica Pharma won accelerated FDA approval for Loargys (pegzilarginase) to treat arginase‑1 deficiency (ARG1‑D) in patients aged two and older, reviving a once‑rejected enzyme replacement therapy for an ultrarare urea‑cycle disorder. The approval targets a population of roughly 250 U.S. residents and follows Immedica’s acquisition of the arginine‑specific enzyme program. Regulators cited clinical data showing biochemical correction of hyperargininemia and expect Loargys to address severe neurological symptoms tied to elevated arginine. The accelerated pathway requires confirmatory post‑approval commitments and highlights the FDA’s willingness to clear treatments for debilitating, extremely rare metabolic disorders when unmet need is acute.