Breakthrough: First Gene Therapy for Hearing Loss
On April 23, 2026, the U.S. FDA approved Regeneron's gene therapy Otarmeni (formerly DB-OTO) for treating hearing loss caused by mutations in the OTOF gene. This is the first approved genetic medicine for inherited hearing loss, marking a major milestone in auditory medicine.
Disease Background: OTOF Mutations and Hearing Loss
The OTOF gene encodes otoferlin, a protein expressed in inner hair cells of the cochlea that regulates signal transmission between sensory cells and the auditory nerve. Mutations lead to lack of functional otoferlin and profound hearing loss. The condition is ultra-rare, affecting about 50 newborns annually in the U.S.
Mechanism: One-Time Infusion to Restore Natural Hearing
Otarmeni uses an engineered viral vector to deliver a functional copy of the OTOF gene into cochlear hair cells. Administered via intracochlear infusion under general anesthesia (similar to cochlear implant surgery), the cells then produce otoferlin protein. This one-time treatment aims to restore natural acoustic hearing, avoiding the robotic quality of cochlear implants.
Clinical Trial Results
The CHORD trial enrolled 25 patients aged 10 months to 16 years, excluding those with prior cochlear implant in the treated ear. Key findings:
- 11 of 12 evaluable patients showed clinically meaningful hearing improvement, with 3 achieving normal hearing.
- Longer follow-up showed stable or continued improvement in 8 patients.
- FDA reported 80% of 20 evaluable patients experienced improved hearing.
Pricing and Business Strategy
Regeneron announced it will provide Otarmeni for free. The approval comes with a Rare Pediatric Disease Priority Review Voucher, which the company can sell to other drugmakers, potentially worth hundreds of millions of dollars.