This is an open-label extension study of a single intratympanic injection of OTO-104 given every 3 months for a total of 2 injections. Subjects must have completed either Otonomy study 104-201102 (Phase 2b study of OTO-104) or 104-201506 (Phase 3 study of OTO-104) in order to be eligible for this open-label extension study.