A groundbreaking gene therapy has successfully restored hearing in both ears of five children who were born deaf. In collaboration with researchers from the Mass Eye and Ear Hospital in Boston, Massachusetts, the clinical trial in Shanghai, China, marks a significant milestone in medical science.
A model displays the world's smallest hearing aid at its Australian launch, in Melbourne on May 7, 2009. (Photo : WILLIAM WEST/AFP via Getty Images)
Revolutionizing Treatment for Genetic Deafness
Currently, over 26 million people worldwide are born with congenital deafness, and there are no pharmaceutical drugs or treatments available to cure genetic deafness. However, recent advancements in gene therapy offer hope for those with inherited deafness.
According to Interesting Engineering, this innovative treatment has the potential to restore hearing and significantly improve the quality of life for millions worldwide.
In this pioneering bilateral trial, doctors administered gene therapy to both ears to address DFNB9. It also involves introducing functional copies of the human OTOF gene through adeno-associated virus (AAV) into the inner ear.
AAV, a modified virus with low pathogenicity, is a safe vehicle for delivering genes into target cells for therapeutic purposes. To deliver this gene to the patients, a specialized, minimally invasive surgery was conducted.
The five children were closely monitored throughout the 13 to 26-week follow-up period. During this time, 36 adverse events were recorded, but none were serious or dose-limiting.
The clinical trial occurred at the Eye & ENT Hospital of Fudan University in Shanghai. This has demonstrated encouraging results in restoring hearing in both ears affected by OTOF gene mutations, which are responsible for autosomal deafness.
Zheng-Yi Chen, study co-senior author and an associate scientist in the Eaton-Peabody Laboratories at Mass Eye and Ear, expressed excitement over the remarkable progress in the hearing ability of treated children.
"We continue to see the hearing ability of treated children dramatically progress and the new study shows added benefits of the gene therapy when administrated to both ears, including the ability for sound source localization and improvements in speech recognition in noisy environments," Chen said in a statement.
The results revealed that all five children experienced hearing improvement in both ears. They demonstrated significant progress in speech comprehension and sound localization.
Remarkably, two children suddenly appreciated music and were observed dancing to music, indicating that the therapy can restore more complex auditory functions beyond hearing.
The primary objective of the research team is to enable patients to perceive sounds in three dimensions, which is crucial for effective communication and essential tasks like driving.
Mutations in the OTOF gene cause a type of hereditary deafness called autosomal recessive deafness 9 (DFNB9). These mutations hinder the production of otoferlin, a vital protein necessary for transmitting sound signals from the cochlea to the brain.
The recent genetic trial was built on the first phase trial, in which the treatment was only given to one of the children's ears. The trial's results were released last January.
