RARE Reports Positive Long-Term Data From Metabolic Disorder Study

Core Insights - Ultragenyx Pharmaceutical (RARE) reported positive long-term data from a late-stage study of its AAV gene therapy, DTX401, for treating glycogen storage disease type Ia (GSDIa), a rare and life-threatening metabolic disorder affecting approximately 6,000 people in commercially accessible regions [1][4] Group 1: Treatment Efficacy - GSDIa patients showed significant reductions in daily cornstarch intake while maintaining low hypoglycemia and improved fasting tolerance after 96 weeks of treatment with DTX401 [2][5] - The DTX401 group achieved a 61% mean reduction in daily cornstarch needs from baseline, with the crossover group also showing similar results [4][7] - Notably, the DTX401 group experienced a 70% mean reduction in nighttime cornstarch intake, and two-thirds of patients eliminated at least one nighttime dose [5][9] Group 2: Patient Quality of Life - Clinical benefits of DTX401 were reflected in significant improvements in patient-reported quality of life, with 83% of patients in the DTX401 group and 95% in the crossover group reporting reduced disease burden [9] - Patients reported fewer hypoglycemic events, decreased tiredness, and improvements in physical, social, and daily functioning [9][10] Group 3: Regulatory Pathway - Ultragenyx initiated the rolling submission of a biologics license application (BLA) to the FDA for DTX401, with completion expected later this year [11][12] - The submission allows the FDA to review key data early while Ultragenyx addresses outstanding questions related to chemistry, manufacturing, and controls [12] Group 4: Market Performance - Year to date, RARE shares have declined by 25.1%, contrasting with the industry's growth of 4.5% [6]