Regeneron's experimental gene therapy for inherited deafness has achieved remarkable clinical success, with 11 of 12 patients experiencing clinically meaningful hearing improvements within weeks of treatment. The breakthrough DB-OTO gene therapy targets mutations in the OTOF gene, an inherited condition that causes profound hearing loss from birth.
The therapy gained international attention through the case of Opal Sandy, who made history in 2023 as the youngest patient worldwide to receive the treatment at just 11 months old. Two years later, the now 3-year-old can hear normally, even without her cochlear implant activated, according to her parents.
Clinical Trial Results
Regeneron announced on October 12 that the clinical trial results exceeded expectations, with nearly all participants showing significant hearing improvements. The therapy involves a 15-minute procedure performed under general anesthesia, during which a working copy of the OTOF gene is delivered directly into the patient's cochlea - the spiral-shaped tube in the inner ear responsible for hearing.
Opal's mother, Jo Sandy, described the transformation as "mind blowing." Prior to treatment, both Opal and her 6-year-old sister Nora, who has the same inherited condition, had no hearing response even to the highest levels of sound testing. "Both girls had no hearing whatsoever," Sandy explained. "So we're talking like big, massive drums and cymbals being banged behind their heads. There was never a response, even at the very highest levels that they can test."
Treatment Approach
The DB-OTO gene therapy represents a novel approach to treating genetic hearing loss by addressing the root cause rather than simply amplifying sound. During Opal's procedure in the United Kingdom, doctors simultaneously delivered the gene therapy to her right ear and placed a cochlear implant in her left ear, providing both genetic correction and traditional hearing assistance.
The treatment specifically targets OTOF gene mutations, which prevent the proper function of cells in the inner ear responsible for converting sound waves into electrical signals that the brain can interpret as hearing.
Expanding Access
The international clinical trial is actively enrolling children under 18 years old across multiple countries, including the United Kingdom, United States, Spain, and Germany. This broad geographic approach aims to provide access to the experimental therapy while gathering comprehensive safety and efficacy data.
Many patients in the trial continue to show hearing progress beyond the initial weeks following treatment, suggesting the therapy's benefits may be sustained and potentially improve over time. The ongoing enrollment indicates Regeneron's commitment to expanding access to this potentially life-changing treatment for children with inherited hearing loss.
