The FDA cleared Ultragenyx’s one-time gene therapy Genglycos (pariglasgene brecaparvovec; DTX-401) for glycogen storage disease type Ia (GSDIa), marking both an accelerated approval and Ultragenyx’s first approved gene therapy. The treatment is designed to deliver a functional gene to the liver to address the underlying enzyme deficiency that drives life-threatening blood sugar instability between meals. Regulators’ approval covers patients aged 8 and older. Pricing and access plans were described publicly by Ultragenyx alongside the approval decision, with expected availability at specialized treatment centers within about 30 to 60 days. The clearance strengthens Ultragenyx’s rare-disease platform after prior regulatory setbacks, and also positions the company to monetize gene therapy know-how and related opportunities, including potential priority review voucher economics tied to its broader pipeline.