Previously deaf toddler can hear after single-jab gene treatment

Results of therapy for 18-month-old girl ‘better than we hoped or expected’

A deaf toddler is now able to hear after becoming the first patient in the world to receive a new gene therapy.

Opal Sandy, an 18-month-old girl from Oxfordshire in England, was born with a genetic form of a condition called auditory neuropathy, which disrupts nerve impulses travelling from the inner ear to the brain and prevents sound being processed.

Last September, she became the first person in the world to receive gene replacement treatment as part of a global trial, and experts are excited by the “potential cure” for the condition.

Opal, like her five-year-old sister Nora, was born with a faulty version of the OTOF gene, which carries the instructions for a neurotransmitter to be produced that allows the ear to communicate with the brain. The malfunction causes severe hearing loss.

Nora’s diagnosis meant Opal was eligible for genetic testing on the NHS, which detected she also had the faulty gene. The condition had not been picked up by newborn screening tests in either child.

While Nora has cochlear implants in both ears, which are the current gold-standard treatment, Opal was able to join the gene therapy trial, although she also has an implant in one ear as a safety measure.

The gene therapy, called DB-OTO and manufactured by Regeneron, works by replacing the faulty gene with a working version. It is administered by a single injection of a modified and harmless virus carrying the new genetic material.

The treatment means the ear’s sensory cells are able to produce a protein called otoferlin that is required for the tiny hair cells in the ear to transmit signals to the brain.

Opal’s parents, Jo and James Sandy, noticed improvements after just three weeks and things have only improved since. Opal’s doctors say her hearing is now “almost normal for her age”, although progress will become clearer as she learns to talk.

Jo Sandy, a 33-year-old geography teacher, said it was “bonkers” how quickly her daughter became able to hear.

“We were in the routine of testing quite loud sounds like banging, clapping, wooden spoons on saucepans, that kind of really intermittent loud noise,” she said.

“I was testing that with her implant on and hadn’t realised that her implant had actually come off, and she turned to pretty loud clapping. When she first turned, I couldn’t believe it.

“I thought it was a fluke or like a change in light or something that had caught her eye, but I repeated it a few times. I was absolutely gobsmacked.”

Opal, who had her surgery at Addenbrooke’s Hospital in Cambridge, is one of up to 18 children due to be enrolled on the trial in the UK, US and Spain.

Professor Manohar Bance, an ear surgeon and the trial’s chief investigator, said the results were “better than I hoped or expected” after 24 weeks.

“We have results from Opal which are very spectacular − so close to normal hearing restoration,” he said. “So we do hope it could be a potential cure.”