 Exploratory analyses for secondary outcomes will assess 1 cochlear damage, specifically hair cell function obtained from the results of DPOAEs, ands 2 the difference between the PTS in dB at pure tone averages 0.5 to 8 kHz, which represent frequencies for speech perception. Other outcomes considered are ototoxicity severity according to CTCAE, and adverse effects of the transtympanic injections. 