The world’s first gene therapy for deafness received approval from the U.S. Food and Drug Administration today. The treatment, from biotech company Regeneron, targets hearing loss caused by inherited mutations in the OTOF gene, which encodes otoferlin, a protein that allows the inner ear’s hair cells to sense and transmit sound to the brain. Patients receive a one-time ear injection containing viral vectors that carry a working copy of the OTOF gene into their cells. In a clinical trial, nine of 12 deaf children who initially received the Regeneron therapy gained enough hearing to stop using cochlear implants; three within that group ended up having normal hearing. Although many gene therapies cost $1 million or more, Regeneron said its treatment, called Otarmeni, will be free in the United States.
Eli Lilly & Co. and researchers in China are also developing gene therapies for OTOF mutations, which account for up to 3% of cases of inherited deafness. One U.S.-Chinese team reported in Nature this week that among 24 patients, including some adults, hearing improvements have lasted more than 2 years in some cases, NPR reports. Researchers eventually hope to treat other types of genetic deafness as well, but those attempts face more challenges. For example, for some disorders, it may be necessary to regenerate lost hair cells. In others, targeting the wrong cell type could damage hearing.









