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 Large Vestibular Aqueduct Syndrome (LVAS), Meniere's disease, or cochlear hydrops
• Ossification, otosclerosis, malformation or any other cochlear anomaly, such as common cavity, that might prevent complete insertion of the electrode array, as confirmed by imaging, in the ear to be implanted
• Current cerebrospinal fluid (CSF) shunts or drains, existing perilymph fistula, temporo- parietal skull fracture or CSF leaks
• History of bacterial meningitis
• Known allergic reaction or contraindication to dexamethasone or corticosteroids
• Severe, or poorer, bilateral sensorineural hearing loss prior to 5 years of age, as reported by the subject
• Severe, or poorer, sensorineural hearing loss of more than 20 years, as reported by the subject, in the ear to be implanted
• Prior cochlear implantation, in either ear
• Medical plan for cochlear implantation during the clinical investigation, contralateral to the ear to be implanted
• Medical or psychological conditions that contraindicate general anaesthesia, surgery or participation in the clinical investigation, as determined by the investigator
• Women who are pregnant
• Unrealistic expectations on the part of the subject, regarding the possible benefits, risks, and limitations that are inherent to the surgical procedure(s) and prosthetic devices as determined by the Investigator
• Additional disabilities that may affect the subject's participation or safety during the clinical investigation, as determined by the Investigator
• Unable or unwilling to comply with the requirements of the clinical investigation as determined by the Investigator
• Investigator site personnel directly affiliated with this study and/or their immediate families; immediate family is defined as spouse, parent, child, or sibling to the study candidate
• Cochlear employees or employees of Contract Research Organisations or contractors engaged by Cochlear for the purposes of this investigation
• Current participation, or participation in another interventional clinical study/trial in the past 30 days, involving an investigational drug or device (unless Cochlear sponsored and determined by investigator or Sponsor to not impact this investigation)
• Subjects recruited at a French site who are not affiliated with social security
• Subjects recruited at a French site who are under legal protection.