Performance and Hearing-related Outcomes in Adults Implanted With the CI622D Dexamethasone-eluting Cochlear Implant Compared to Those Implanted With a Standard Cochlear Implant (CI622)

Inclusion Criteria: * Aged 18 years or older (at time of consent) * Clinically established post-linguistic bilateral moderately severe to profound sensorineural hearing loss * Meets local candidacy criteria for cochlear implantation * Compromised functional hearing with a hearing aid in the ear to be implanted * Willing to participate in and comply with all requirements of the protocol, including willingness to be randomised to either arm * Evidence of pneumococcal vaccination (e.g., Pneumovax) according to local guidelines prior to randomisation * Candidate is proficient in the language used to assess speech perception performance * Willing and able to provide written informed consent. Exclusion Criteria: * Planned for a partial insertion of the electrode array * Intra-axial (within the brain) lesions or deafness due to lesions of the acoustic nerve affecting the ear to be implanted * Middle ear infection (including acute otitis media, chronic otitis media, suppurative otitis media, or serous drainage) in the ear to be implanted either at the time of surgery or within 3 months prior to enrolment * Active autoimmune disease or active immunosuppressive therapy * Any of the following in the ear to be implanted within 3 months prior to enrolment: history of prior otologic surgery including grommets, or tympanic membrane perforation * Previously reported diagnosis of auditory neuropathy, in the ear to be implanted * Previously reported diagnosis, in the ear to be implanted, of…