United States, Sept. 17 -- The U.S. Food and Drug Administration approved Fayuvi (rebisufligene etisparvovec-hopf), the first treatment for pediatric patients with mucopolysaccharidosis type IIIA (MPS IIIA), also known as Sanfilippo syndrome type A., MPS IIIA is a rare inherited disease that progressively damages the brain and nervous system, causing children to lose cognitive, language and other developmental abilities over time. Until today, treatment was limited to managing symptoms; there was no FDA-approved therapy designed to change the underlying course of the disease. Fayuvi is a one-time, intravenous (given directly into a vein) gene therapy that uses a modified, non-infectious virus called an adeno-associated virus serotype 9 (AAV...