Study of OTO-104 in Subjects With Unilateral Meniere's Disease

Inclusion Criteria includes, but is not limited to: * Subject has a diagnosis of unilateral Meniere's disease by 1995 American Academy of Otolaryngology - Head and Neck Surgery (AAOHNS) criteria and reports active vertigo for the 2 months prior to the study lead-in period. * Subject has experienced active vertigo during the lead-in period. * Subject has documented asymmetric sensorineural hearing loss. * Subject agrees to maintain their current treatments for Meniere's disease while on-study. Exclusion Criteria includes, but is not limited to: * Subject is pregnant or lactating. * Subject has a history of immunodeficiency disease. * Subject has a history of previous endolymphatic sac surgery. * Subject has a history of previous use of intratympanic (IT) gentamicin in the affected ear. * Subject has a history of tympanostomy tubes with evidence of perforation or lack of closure. * Subject has experienced an adverse reaction to IT injection of steroids. * Subject has used an investigational drug or device in the 3 months prior to screening. * Subject has previously been randomized to a trial of OTO-104.