Up to three out of every 1,000 newborns is born experiencing hearing loss in one or both ears. Although cochlear implants have been a transformative option for a long time, they require surgery and cannot completely mimic the nuances of natural hearing. However, researchers may have finally discovered an alternative approach.
Recent studies indicate that scientists have effectively utilized gene therapy to revive hearing in adults with congenital deafness, representing a significant milestone in the effort to restore hearing across various age groups.
A genuine champion in hearing recovery
It is well acknowledged that gene therapy can be remarkably potent. Not only has gene editing opened avenues for numerous potential therapies, but it has also set the stage for revolutionary research, such as hypoallergenic cats, among others.
This innovative treatment can restore hearing in adults by addressing a rare type of genetic hearing loss termed OTOF-related deafness. This condition arises from mutations in the OTOF gene, which is responsible for producing a protein called otoferlin. Otoferlin is essential for transmitting sound signals from the inner ear to the brain.
In patients with this mutation, that signal chain is disrupted. This results in hearing impairment from birth onwards. However, since the inner ear structures remain intact, the condition is particularly amenable to gene therapy interventions. To insert a functional copy of the OTOF gene, researchers employed a safe, modified virus that was introduced directly into the sensory cells of the inner ear. This virus served as a messenger, delivering the corrected gene into the cells, enabling them to start producing otoferlin and potentially restore sound signaling.
Swift advancements
Preliminary tests in children indicated encouraging outcomes, yet a larger question persisted: Could gene therapy be effective in older patients? To investigate, the team initiated a clinical trial with 10 participants aged between 1 and 24, all diagnosed with OTOF-related deafness. The outcomes were positive across the board—and particularly remarkable in older participants.
The enhancements in hearing were both quick and substantial. On average, participants exhibited a 62% improvement in brainstem response evaluations and a 78% increase in behavioral hearing assessments. Some individuals were able to perceive speech sounds within just a few weeks. This research signifies the first instance in which gene therapy has been demonstrated to restore hearing in both adolescents and adults.
