Regeneron announced plans to seek regulatory approval after New England Journal of Medicine–published data showed its gene therapy produced measurable hearing improvements in nearly a dozen children with a rare genetic deafness. The trial, led by Regeneron investigators and reported in NEJM, documents functional gains rather than only biomarker shifts. The study enrolled pediatric patients with a specific monogenic form of hearing loss and reported audiologic improvements following a single administration. The results mark a transition from early-stage safety studies to an efficacy dataset Regeneron will use in its regulatory submission. Regeneron intends to file with regulators based on the NEJM data; the company will need to expand datasets and define long-term durability and safety endpoints for labeling. Clinicians and payers will watch follow-up cohorts and durability analyses closely as the therapy moves toward market authorization.