The limitations of hearing aids
Hearing relies heavily on the inner ear, specifically the cochlea, where hair cells detect sound and convert it into electrical signals that travel to the brain via specialised auditory neuron cells.
Damage to these sensory cells is responsible for about 90% of hearing loss, known as sensorineural hearing loss.
Although hearing aids and cochlear implants can overcome issues with hair cells, they cannot restore the neurons’ role in processing important aspects of sound, such as distinguishing speech from background noise or determining where a sound is coming from.
As Pam has found: “My hearing aid makes sounds louder but that also includes things like air conditioning or other people chatting when you’re trying to listen to someone. It takes a lot of effort to differentiate sounds, and concentrating that hard can be exhausting by the end of the day.”
New cells could restore natural hearing
As we age, the number of sensory cells in our ears decreases, and these cells can also be damaged by exposure to loud noises or certain chemicals.
Right now, there is no way to repair or replace lost or damaged cells. Researchers at Rinri Therapeutics, however, are developing a new treatment designed to address this problem.
They are harnessing the power of stem cells, which can become any type of cell in the human body, transforming them into ‘auditory progenitors’, the early forms of sensory cells in the ear.
The idea is to replace damaged cells with functional ones, says Dr Simon Chandler, CEO of Rinri Therapeutics.
He explains: “The auditory progenitors we develop in a lab can be injected into the inner ear, where they will then mature into functional auditory neurons. These new neurons re-establish broken connections to the brain and have the potential to bring back natural hearing.”
From Sheffield lab to global impact
The groundbreaking treatment builds on more than 20 years of stem cell research that started with Rinri Therapeutics’ founder, Professor Marcelo Rivolta, at The University of Sheffield.
In 2021 the company received £2.6 million funding from UK Research and Innovation (UKRI), which invests taxpayers’ money into research and innovation to improve people’s lives. The funding helped Marcelo and his team take his research from the lab to real-world patients.
This year will see the first trial of this pioneering treatment in people.
If it successfully passes clinical trials and regulatory requirements, it could be available to patients within a decade, either as a stand-alone solution or used alongside devices like cochlear implants.
“It has the potential to enhance how patients perceive sound. Think of it like your television: a cochlear implant or hearing aids offer a pixelated image, but restoring thousands of sensory cells could give you back much higher, natural, resolution,” explains Simon.
Bringing back the sound of laughter
The benefits for people with hearing loss could be life changing.
On a practical level, there would no longer be a need to worry about hearing aid batteries dying or having to remove them before showering or swimming.
More significantly, regaining the ability to truly hear the world around them could bring profound improvements to quality of life.
As Pam puts it: “It means young mums being able to hear their baby laugh and cry, and those first words. It means having conversations without constantly saying ‘pardon’. It’s about having those connections.”
