Aug 11, 2026 —
Skylark Bio announced that the first patient has been dosed in the SONIX Phase 1/2 clinical trial evaluating SKY-GJB2, its investigational inner-ear-targeted AAV gene therapy for GJB2-mediated hearing loss.
GJB2-related hearing loss is the most common genetic cause of nonsyndromic deafness and one of the most prevalent monogenic forms of pediatric hearing loss. The disorder is caused by genetic changes in GJB2, which disrupt the function of connexin 26, a protein essential for the gap-junction network of the inner ear and normal hearing function.
There are currently no approved disease-modifying treatments for GJB2-related hearing loss. Existing interventions, including hearing aids and cochlear implants, can provide partial access to sound but do not address the underlying genetic cause or restore natural hearing.
SKY-GJB2 is designed as a potential first-in-class AAV-delivered therapy to address the underlying cause of GJB2-related hearing loss. The therapy is intended to deliver a functional copy of GJB2 to supporting cells in the cochlea that naturally express connexin 26, with the goal of restoring the gap-junction network essential for hearing.
The SONIX trial is a multicenter, open-label Phase 1/2 study designed to assess the safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary efficacy of a single unilateral intracochlear injection of SKY-GJB2.
The study is enrolling children aged 9 months to 7 years, a population in which early intervention may be important for hearing development and spoken-language acquisition.
Skylark expects preliminary data from SONIX by year-end 2026, with additional readouts anticipated in 2027.
The company said the recent approval of a targeted inner-ear AAV-delivered therapy provides important validation for the hearing-loss gene therapy field and reinforces confidence in locally delivered AAV approaches for monogenic hearing disorders.
The first patient dosing marks an important step for Skylark’s targeted genetic medicine platform, which is focused on monogenic diseases where precise local delivery and disease-relevant, cell-specific expression are critical to therapeutic success.
