Gene Therapy Experiment Restores Hearing in Five of Six Children with Deafness

Researchers have reported that a gene therapy being developed by a Chinese company has restored hearing in children suffering from congenital deafness, supporting increasing evidence of the effectiveness of such treatments. According to a report published in The Lancet medical journal, five out of six young children with profound hearing loss experienced improvements in their hearing as well as enhancements in speech recognition six months after undergoing the treatment developed by Refresh Gene Therapeutics. All the children suffered from severe deafness caused by mutations in the OTOF gene (otoferrin). The otoferrin protein is essential for transmitting sound signals from the ear to the brain. Previous research indicates that mutations in this gene account for 2 to 3 percent of congenital deafness cases. One in every thousand newborns in the United States experiences moderate to severe hearing loss. The researchers conducted surgical interventions at the Ear, Nose, and Throat Hospital of Fudan University, using a harmless virus to deliver a copy of the human gene to the patients' inner ears. After 26 weeks, the researchers announced that five of the six children showed signs of improved hearing, along with significant improvement in speech perception and the ability to engage in conversations. The researchers added that the side effects were mostly mild and did not have any long-term impact. They are unsure why the sixth child did not respond to the treatment. One possible explanation is that some of the gene therapy solution leaked from the inner ear during or after the surgery.