Our increased understanding of the underlying causes of many hearing disorders has led to the development of molecular therapeutics to address a variety of disorders. The CGF166 (atoh1) human clinical trial has enhanced our ability to model and understand the delivery of viral vectors to the human inner ear and serves as a model for understanding the translation of a range of molecular therapeutics into clinical trials.  Key issues emerging from this study are identification of appropriate models for preclinical testing development of improved testing to aid in patient selection and optimization of delivery approaches.  There has also been a leap forward in the development of synthetic vectors that can target the inner ear.  The next generation of translational studies will address a broader range of inner ear applications including genetic hearing loss, protection of the inner ear and modification of cellular phenotype.