NOVATO, Calif., Feb. 23, 2026 (GLOBE NEWSWIRE) —Ultragenyx Pharmaceutical Inc. has announced that the U.S. Food and Drug Administration (FDA) has accepted for review its Biologics License Application (BLA) for DTX401 (pariglasgene brecaparvovec), an investigational AAV8 gene therapy for Glycogen Storage Disease Type Ia (GSDIa). The application has been granted Priority Review, with a Prescription Drug User Fee Act (PDUFA) action date of August 23, 2026.
DTX401 is designed as a single intravenous AAV8 gene therapy to deliver stable expression of the G6PC gene, which encodes glucose-6-phosphatase (G6Pase). By restoring G6Pase activity in liver cells, the therapy aims to address the root cause of GSDIa, enabling physiological glucose regulation and reducing dependence on strict dietary management.
The BLA submission is supported by data from 52 treated patients across the clinical development program, including up to six years of follow-up. Results from the Phase 3 GlucoGene study demonstrated significant and clinically meaningful reductions in both the quantity and frequency of daily cornstarch intake, while maintaining improved glycemic control and fasting tolerance. Patients also reported meaningful quality-of-life improvements, as measured by the Patient Global Impression of Change (PGIC) scale. The therapy was generally well tolerated with an acceptable safety profile.
If approved, DTX401 would become the first disease-modifying treatment for GSDIa. Manufacturing of the AAV8 gene therapy will be conducted entirely in the United States at Ultragenyx’s gene therapy facility in Bedford, Massachusetts.
DTX401 has previously received Rare Pediatric Disease, Orphan Drug, Fast Track, and Regenerative Medicine Advanced Therapy (RMAT) designations from the FDA, as well as Orphan Drug and PRIME designations from the European Medicines Agency.
GSDIa is a rare, life-threatening metabolic disorder caused by pathogenic variants in the G6PC gene, leading to deficient G6Pase activity. Patients experience severe fasting hypoglycemia, excess hepatic glycogen accumulation, and long-term metabolic complications. Current management relies heavily on frequent cornstarch dosing to maintain blood glucose levels, placing a significant burden on patients and families. There are currently no approved pharmacologic therapies. The disease is estimated to affect approximately 6,000 individuals in commercially accessible regions.
