Akouos, Inc., a wholly owned subsidiary of Eli Lilly and Company announced positive initial clinical results from the Phase 1/2 AK-OTOF-101 study, which demonstrated pharmacologic hearing restoration within 30 days of AK-OTOF administration in the first participant, an individual with a decade-plus history of profound hearing loss. Results, including initial data from a second participant to receive AK-OTOF, will be presented during the Late Breaking Presidential Symposium at the 2024 Association for Research in Otolaryngology (ARO) MidWinter Meeting. The first participant to receive AK-OTOF in the study, an 11-year-old at the time of AK-OTOF administration with profound hearing loss from birth, experienced restored hearing within 30 days of AK-OTOF administration.

In this individual, hearing was restored across all tested frequencies, achieving thresholds of 65 to 20 dB HL, and within the normal hearing range at some frequencies at the Day 30 visit. Both the surgical administration procedure and the investigational therapy were well tolerated, and no serious adverse events were reported. In the AK-OTOF-101 trial, eligible participants receive a single, unilateral intracochlear administration of AK-OTOF, with hearing restoration assessed by behavioral audiometry and auditory brainstem response (ABR), a clinically accepted and objective measure of hearing sensitivity.

Participants in cohort 1 receive AK-OTOF at a dose of 4.1E11 total vector genomes. Hearing loss is the most common sensory condition, and with no approved pharmacologic treatments to restore hearing, represents a significant area of unmet need in medicine. Millions of individuals worldwide have disabling hearing loss because one of their genes generates an incorrect or incomplete version of a protein the ear requires for hearing.

In many of these cases ? including for some of the estimated 200,000 individuals worldwide who live with OTOF-mediated hearing loss ? delivering a healthy version of the gene to a target cell within the inner ear has the potential to restore auditory function and enable high-acuity physiologic hearing.

OTOF-mediated hearing loss is the first monogenic form of hearing loss to be investigated as part of a gene therapy clinical trial. AK-OTOF (AAVAnc80-hOTOF) is a dual adeno-associated viral (AAV) vector-based gene therapy designed to restore auditory function by gene transfer and durable expression of normal, functional otoferlin protein to the inner hair cells of the cochlea. AK-OTOF utilizes AAVAnc80, a capsid with high transduction efficiency for inner hair cells, together with a strong ubiquitous promoter to achieve expression of otoferlin, observed only in the target inner hair cells, at levels that have the potential to restore high acuity physiologic hearing.

The Akouos delivery device, being developed in parallel specifically for intracochlear administration, enables a minimally invasive surgical approach to deliver AK-OTOF throughout the cochlea. The AK-OTOF-101 Clinical Trial (NCT05821959) is a Phase 1/2 trial that is assessing the safety, tolerability, and bioactivity of escalating doses of AK-OTOF delivered via the Akouos delivery device. The AK-OTOF-NHS-002 Natural History Study (NCT05572073) is designed to characterize the natural history of OTOF-mediated hearing loss, including progression of physiologic responses and audiologic outcomes over time, potential genotype-phenotype relationships, and longitudinal assessment of clinical outcomes.