The US Food and Drug Administration (FDA) has approved Fayuvi (rebisufligene etisparvovec-hopf; UX111) for the treatment of pediatric patients with mucopolysaccharidosis type IIIA (MPS IIIA; Sanfilippo syndrome type A).
MPS IIIA is a genetic neurodegenerative disorder characterized by the inability to break down heparan sulfate due to mutations in the SGSH gene. Affected individuals can have severe neurological symptoms, including progressive dementia, aggressive behavior, hyperactivity, seizures, deafness, loss of vision, and an inability to sleep for more than a few hours at a time.
UX111 is a single-dose intravenous AAV9 gene therapy designed to deliver a functional copy of the deficient enzyme gene that can express and replace the missing SGSH enzyme. It is the first-ever FDA-approved treatment for MPS IIIA.
The approval is based on data from the pivotal Transpher A clinical trial (NCT02716246) and long-term follow-up studies. Treatment with UX111 demonstrated clinical benefit relative to the decline observed in natural history, as well as a durable treatment effect across clinical assessments and multiple biomarkers. UX111 also maintained an acceptable safety profile.
Additionally, UX111 demonstrated biochemical efficacy in replacing the missing SGSH enzyme through reduction in accumulated cerebral spinal fluid heparan sulfate levels throughout the study and across all age groups.
Clinical efficacy was assessed based on patients’ mean change in Bayley-III Cognitive raw score from 24 to 60 months of age. UX111-treated patients from the modified intention-to-treat population were compared to untreated patients with MPS IIIA from an external, comparable natural history cohort. UX111-treated patients demonstrated a 23.5 point higher cognitive score over natural history during the period of study.
Ultragenyz also received a Priority Review Voucher upon this approval.
For more information, click visit https://ir.ultragenyx.com/news-releases/news-release-details/ultragenyx-announces-approval-fayuvitm-gene-therapy-first-ever
To learn more about MPS IIIA and other rare metabolic conditions, visit https://checkrare.com/diseases/metabolic-disorders/