Local medical experts received wide attention after sharing the data and clinical effects of the world's first successful gene therapy clinical trial on congenital deafness, at the annual congress of European Society of Gene and Cell Therapy, the Eye and ENT Hospital of Fudan University in Shanghai said on Tuesday.

Experts said the first batch of children receiving innovative gene medicine has since been able to speak. It indicates the arrival of gene therapy to treat deafness, and boost the clinical application of gene treatment for congenital deafness.

The ESGCT congress is one of the most authoritative international conferences on gene and cell therapy in the world. This year's congress, from last Tuesday to Friday in Belgium, attracted over 2,500 top experts, scientists, researchers and industry insiders, who shared and exchanged their latest achievements in research, technical progress and innovative treatment.

Dr Shu Yilai, director of the hospital's inherited deafness diagnosis and treatment center, was invited by the conference to share their latest achievements.

There are 26 million people with congenital deafness in the world. In China, about 30,000 deaf children are born each year, 60 percent of them due to hereditary reasons, greatly impacting their hearing, language and intelligence development. But there is no effective medicine.

The OTOF genetic mutation is an important factor in causing serious hearing loss and language disorder in children. To deal with the issue, local experts cooperated with international colleagues and pharmaceutical companies to develop gene medicine, creating a new era for deafness treatment.

The RRG-003 is an adeno-associated viral vector (AAV)-based gene therapy, which delivers normal or medicative genes into target cells, to compensate or correct defective or abnormal 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.

The clinical trial started in October, 2022 and doctors finished the first case treatment in December, 2022. The first child who received the injection has regained hearing for over 10 months and is able to have daily conversation, said the hospital, which has finished multiple cases of clinical trails, and is expanding the trial scale by recruiting more patients.