Local medics develop first successful gene therapy for inherited deafness

Local medics have developed the world's first successful gene therapy for hereditary deafness, providing new hope for patients.

There are 26 million people around the world with congenital deafness. About 30,000 children are born deaf in China each year with 60 percent of the cases related to genetic defects, seriously impacting their language, cognition and intelligence development. There is no effective medication so far.

With the development of biomedicine, gene therapy is believed one of the most promising treatments for hereditary deafness. It can deliver genes with proper function directly into the inner ear to help patients regain their hearing.

Dr Shu Yilai, of the Eye, Ear, Nose and Throat Hospital of Fudan University, has been dedicated to genetic treatment on deafness for the past decade. His team successfully developed a genetic medicine RRG-003 targeting deafness due to OTOF genetic mutation with a precise and minimally invasive drug delivery route and equipment.

The OTOF genetic mutation is an important factor in causing serious hearing loss and language disability among children. It is the reason for 41 percent of Chinese children with auditory neuropathy.

The RRG-003 is an Adeno-Associated Virus (AAV)-based gene therapy, which delivers normal OTOF genes into target cells, to correct patients' defective genes, realizing disease treatment and renovating hearing. Now the medicine is injected into the inner ears to help children with OTOF mutation to regain or improve hearing and language.

A clinical trial began in October, 2022 and doctors finished the first case treatment in December the same year. The first child who received the injection has regained hearing for over 12 months and is able to have daily conversations, said the hospital, which has completed six cases of clinical trails, and five children have significant renovation of hearing and language ability.

It is the world's first gene therapy on deafness genes with effects and also the first systematic clinical trial with the largest number of participating patients.

The research was published by world-leading journal The Lancet on Thursday.