Ultragenyx Announces FDA Full Approval for FAYUVI™, First-Ever Gene Therapy for MPS IIIA

Ultragenyx Pharmaceutical Inc. announced it received standard full approval from the U.S. Food and Drug Administration (FDA) for FAYUVI™ (rebisufligene etisparvovec-hopf), a gene therapy for pediatric patients with mucopolysaccharidosis type IIIA (MPS IIIA), also known as Sanfilippo syndrome Type A. This marks the first-ever approved treatment for this progressive and fatal neurodegenerative disease.

Key Details

• Product: FAYUVI™ (also known as UX111) received standard full FDA approval on September 17, 2026.
• Significance: This is the first approved therapy for Sanfilippo syndrome Type A and the second gene therapy approval for Ultragenyx.
• Incentive: The company was granted a Priority Review Voucher (PRV) by the FDA in conjunction with the approval.