OTO-413 in Subjects With Speech-in-Noise Hearing Impairment

Inclusion Criteria: * Subject has audiometrically-defined normal hearing or up to moderately severe hearing impairment. * Subject has self-reported difficulty hearing in noisy environments for at least 6 months prior to Screening. * Subject exhibited a speech-in-noise hearing deficit in at least one ear. Exclusion Criteria: * Subject is pregnant or lactating. * Subject has the following hearing disorders or any other hearing disorders that may impact the efficacy assessments or safety of the subject in the opinion of the Investigator: Meniere's disease, congenital hearing loss, or genetic sensorineural hearing loss. * Subject has a cochlear implant or consistently uses a hearing aid. * Subject has worked at least 5 years as a professional musician or has had at least 15 years of formal musical training. * Subject self-reports bothersome, subjective tinnitus and is consistently aware of their tinnitus throughout much of the waking day.