Can a gene therapy restore natural hearing after cochlear implants?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Subjects must meet all of the following inclusion criteria to be enrolled in the study: 1. Age between 1 year and 17 years (inclusive) at the time of signing the ICF, male or female; 2. Confirmed homozygous or compound heterozygous mutation in the OTOF gene as documented in a report issued by a qualified genetic testing institution; 3. Audiometric testing (reports from within 6 months prior to signing the ICF are acceptable): Severe or profound deafness (Click ABR ≥ 80 dBnHL); 4. Has received cochlear implantation and has reasonable expectations; 5. Vital signs, physical examination, laboratory tests (complete blood count, blood biochemistry, coagulation function, urinalysis, etc.), and 12-lead ECG are all normal or show abnormalities judged by the investigator to be clinically insignificant; 6. Subject and/or their legal guardian signs the informed consent form. Exclusion Criteria: * Subjects who meet any of the following criteria are not eligible for enrollment: 1. Presence of other definite genetic mutations causing deafness other than the OTOF gene that may affect the judgment of the treatment effect of the OTOF investigational drug; 2. History of severe allergic reactions to any drug or its components in this study; 3. Prior gene therapy and/or oligonucleotide drug treatment in the ear that has undergone cochlear implantation; 4. Blood AAV2 neutralizing antibody titer \> 1:2000; 5. Presence of systemic diseases or receipt of related treatments that may affect hearing or surgical procedures; 6. Inability to undergo general anesthesia; 7. History of major inner ear surgery (judged by the investigator as inappropriate for gene therapy); 8. Other types of deafness unsuitable for otologic surgery, such as deafness caused by middle-inner ear developmental abnormalities or malformations, vestibulocochlear nerve abnormalities, conductive hearing loss, mixed hearing loss, or syndromic malformations as detected by CT/MRI; 9. Otologic diseases that may interfere with the planned surgery or interpretation of study endpoints, such as acute-chronic otitis media, Meniere's disease, acoustic neuroma, sudden deafness with no hearing recovery, etc.; 10. History of drug abuse, or receipt of any known ototoxic drug therapy within 6 months (e.g., aminoglycosides, cisplatin, loop diuretics, etc.), or receipt of antiviral and immunosuppressive therapy within 3 months, or vaccination within 1 month; 11. Subjects currently receiving or likely to receive immunosuppressive therapy other than that required for this study; 12. Allergy or intolerance to glucocorticoids; 13. History of malignant tumors or meningitis; 14. Presence of persistent or active infection; subjects who are HBsAg positive with peripheral blood HBV DNA titer above the lower limit of detection; subjects who are HCV antibody positive with peripheral blood HCV RNA titer above the lower limit of detection; subjects who are HIV antibody positive or have other immunodeficiency diseases; subjects with positive syphilis serology; 15. Subjects of childbearing potential who refuse to use effective contraceptive measures (hormonal, barrier methods, or abstinence) from the time of signing the ICF through 12 months after AAV injection; 16. Female subjects of childbearing potential with a positive serum pregnancy test, or who are currently pregnant or breastfeeding; 17. Subjects who have participated in any other clinical study within 4 weeks prior to the first dose and have already received study drug or treatment (including drug and device clinical studies, excluding non-interventional studies); 18. Unwilling or unable to comply with this study protocol; 19. Subjects whom the investigator judges to have any medical condition that renders them unable to participate in this study or complete the subsequent follow-up.