This multi-center, observational, post-intervention long term follow-up (LTFU) study will monitor for safety and efficacy of AAVAnc80-hOTOF in individuals with sensorineural hearing loss due to otoferlin gene mutations who have previously received intracochlear administration of AAVAnc80-hOTOF in the AK-OTOF-101 Clinical Trial.

After completing one year of initial safety and efficacy assessments following an intracochlear administration of AAVAnc80-hOTOF in AK-OTOF-101, participants will continue to be observed for an additional approximately four years of safety and efficacy follow-up in this LTFU study, for a total of approximately five years of safety and efficacy observations after vector administration. For each participant, evaluations in the LTFU study will occur at approximately one and a half years and two years after vector administration, followed by annual visits through Year 5; the duration in this LTFU study is approximately four years, with the aim of understanding and mitigating any risks related to delayed adverse events, as well as characterizing the durability of effect of the AAVAnc80-hOTOF.

Inclusion Criteria:

• Individuals with otoferlin gene-mediated hearing loss who received intracochlear administration of AAVAnc80-hOTOF in the AK-OTOF-101 Clinical Trial
• Legally authorized representative and/or participant willingness to comply with all study requirements, as evidenced by successful completion of the informed consent process or permission and participant assent process (where appropriate)

Exclusion Criteria:

• Any condition that would not allow the potential participant to complete follow-up examinations during the course of the study and/or, in the opinion of the Investigator, makes the potential participant unsuitable for the study

Individuals with otoferlin gene-mediated hearing loss who received intracochlear administration of AAVAnc80-hOTOF in the AK-OTOF-101 Clinical Trial.