RecruitingCombination productOpen-label Study of SKY-GJB2 in Pediatric Subjects With GJB2-mediated Hearing LossSkylark Bio is conducting a study of an investigational new drug called SKY-GJB2 and its delivery device, the SKY-CAT. SKY-GJB2 is a gene therapy that is being developed to treat children who have hearing loss due to changes in the GJB2 gene (also referred to as Connexin 26). The SKY-CAT is a device that delivers the gene therapy. The purpose of this study is to: Learn about the safety and tolerability (does not cause ongoing discomfort) of SKY-GJB2 Evaluate the efficacy of SKY-GJB2 (how well is works)