There are more than 150 different genes that have been identified as causing hearing loss. A rarer gene, the otoferlin (OTOF) gene, was identified in an 11-year-old boy and he was subsequently treated with gene therapy at Children’s Hospital of Philadelphia (CHOP) in October 2023.
The young boy was the first patient to receive this gene therapy in the multicenter study in which CHOP is involved (www.otofclinicaltrial.com; 2024). The patient underwent a surgical procedure where a single, small dose of a gene therapy (adeno-associated viral vector gene therapy, or AK-OTOF) containing copies of the normal OTOF gene was delivered directly to the inner ear. This was the first time a direct injection via the round window into the cochlea has been completed as a treatment for hereditary hearing loss in the United States.
The patient was born profoundly deaf, and now, four months later, his hearing has improved in the treated ear to a mild-moderate hearing loss. He is now hearing things never before possible.
CHOP is one of several clinical trial sites in the world participating in the AK-OTOF-101 clinical trial, sponsored by Akouos, Inc., a wholly owned subsidiary of Eli Lilly and Company.
Dr. John A. Germiller, director of clinical research in the division of otolaryngology at CHOP, reports, “As more patients at different ages are treated with this gene therapy, researchers will learn more about the degree to which hearing is improved and whether that level of hearing can be sustained over many years. What we have learned from following this patient’s progress will help direct our efforts toward helping as many patients as we can.”
References
AK-OTOF-101. (2024). AK-OTOF-101 Study. (accessed January 24, 2024).
Children’s Hospital of Philadelphia. (2024). Children’s Hospital of Philadelphia Performs First in U.S. Gene Therapy Procedure to Treat Genetic Hearing Loss (accessed January 24, 2024).
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