OTO-313 in Subjects With Unilateral Subjective Tinnitus

Inclusion Criteria: * Subject has early-onset subjective unilateral tinnitus that is persistent (consistently aware of their tinnitus throughout much of the waking day). * Subject is able to use the diary to complete their daily tinnitus ratings. * Subject's tinnitus is likely of cochlear origin, e.g., associated with sensorineural hearing loss; acute hearing loss from noise trauma, barotrauma, or traumatic cochlear injury (acute acoustic trauma, blast trauma, middle ear surgery, inner ear barotrauma); age related hearing loss; resolved otitis media; ototoxic drug exposure. * Subject is willing to comply with the protocol and attend all study visits. Exclusion Criteria: * Subject has pulsatile tinnitus, temporomandibular joint disease (TMJ) associated with tinnitus perception, tinnitus resulting from traumatic head or neck injury, or tinnitus resulting from a tumor or stroke. * Subject is pregnant, lactating, or undergoing fertility treatment. * Subject has other clinically significant illness, medical condition or medical history at Screening or Baseline that, in the Investigator's opinion, would likely reduce the safety of study participation or compliance with study procedures.