FDA approves first gene therapy for Sanfilippo syndrome type A

FDA approves first gene therapy for Sanfilippo syndrome type A

The U.S. Food and Drug Administration (FDA) has approved Ultragenyx’s Fayuvi (rebisufligene etisparvovec-hopf) for children with Sanfilippo syndrome type A, also known as mucopolysaccharidosis type IIIA (MPS IIIA).

The approval makes Fayuvi the first disease-modifying treatment approved for this rare inherited neurodegenerative disorder.

Sanfilippo syndrome type A progressively damages the brain and nervous system, causing children to lose cognitive, language, and other developmental abilities over time. Patients with the condition have an average life expectancy of around 15 years.

Fayuvi is a one-time gene therapy that uses an AAV9 viral vector to deliver a functional copy of the SGSH gene into a patient’s cells. This enables the body to produce sulfamidase, an enzyme that is missing or deficient in people with MPS IIIA.

Clinical trial data showed that a single intravenous administration of the therapy maintained or improved cognitive function compared with an untreated historical control group.

Fayuvi will have a U.S. list price of $3.95 million, making it one of the most expensive medicines currently on the market. According to Ultragenyx, lifetime care costs for a child with Sanfilippo syndrome type A can exceed $8 million.

The therapy will be administered through a network of qualified treatment centers specifically trained to provide gene therapy.