Regeneron Pharmaceuticals Inc. (NASDAQ: REGN) announced the European Medicines Agency has accepted its Marketing Authorization Application for Otarmeni, a gene therapy for biallelic OTOF variant-associated hearing loss, under accelerated assessment review.

Otarmeni, formerly known as DB-OTO, is an adeno-associated virus vector-based gene therapy delivered through intracochlear infusion. The therapy previously received Orphan Designation from the EMA and would be the first gene therapy for OTOF-related hearing loss in the European Union if approved.

The application is supported by data from the CHORD clinical trial, which enrolled 24 participants aged 10 months to 16 years. Participants received a single dose either in one ear (10 participants) or both ears (14 participants). Earlier data from this trial also supported the FDA's accelerated approval of Otarmeni in April 2026.

OTOF-related hearing loss affects approximately 46 newborn children per year in the EU. The condition results from variants in the OTOF gene that prevent production of functional otoferlin protein, which is necessary for communication between inner ear sensory cells and the auditory nerve.

The ongoing CHORD trial is a Phase 1/2 multicenter study evaluating safety and efficacy across sites in the United States, United Kingdom, Spain, Germany and Japan. The trial includes a dose-escalation phase with single-ear treatment and an expansion phase with bilateral treatment.

Regeneron plans additional regulatory submissions in markets including Japan. The company stated that outside the United States, the safety and efficacy of Otarmeni have not been fully evaluated.