A gene therapy for a rare form deafness receives FDA approval : NPR


Sierra Smith holds her son, Travis, whose deafness was successfully treated with gene therapy.

Sierra Smith holds her son, Travis, whose deafness was successfully treated with gene therapy.

Regeneron Pharmaceuticals


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Regeneron Pharmaceuticals

The Food and Drug Administration approved the first gene therapy to restore hearing for people who were born deaf.

The decision, while only immediately affecting people born with a very rare form of genetic deafness, is being hailed as a milestone in the quest to treat hearing loss.

“It’s the first time in history there’s a new drug for hearing loss,” says Zheng-Yi Chen, an associate scientist at Mass Eye and Ear in Boston who was not involved in the development of the therapy approved by the FDA Thursday. But his research team reported very promising results with a similar approach Wednesday. “I think it’s an historical event, a landmark, a great development for the whole field,” he says of the approval.

A newborn’s failed hearing test 

When Sierra Smith gave birth to her son, Travis, the hospital immediately told her something was wrong.

“The hospital told me that he failed his newborn hearing test. But they thought it was just fluid in the ears and that it would be fine in a couple of months,” says Smith, 26, who lives in East Greenbush, N.Y.

But he wasn’t. It turned out Travis was born with a rare genetic defect that had left him profoundly deaf.

“He was 100% deaf,” Smith says. “Everything we do — slamming pots and pans together, yelling his name – there was nothing at all.”

An experimental gene therapy offers hope

How the treatment works

Doctor infused billions of adeno-associated viruses into the patients’ ears by making a small incision behind the ear to open a small hole in the skull. The viruses carried a healthy version of the OTOF gene that had been split in half to fit inside the virus. The gene provides instructions to make the otoferlin protein, which is necessary for hair cells in the inner ear to transmit sound to the brain.

Most of the patients began to hear for the first time within weeks, with the quality of their hearing improving over the following months, according to Regeneron. The amount of hearing patients gained varied, but 80% achieved at least some significant hearing restoration and 42% ended up with normal hearing, which included the ability to hear whispers, Regeneron says. The hearing ability has lasted at least two years so far.

“These are incredible results for somebody like me who been in this field for a couple of decades. It’s something I hadn’t imagined only a few years ago could be possible,” Whitton says. “What we’ve seen has been quite remarkable.”

The treatment can only help patients with the very rare form of deafness that Smith was born with, which only affects about 50 children each year in the U.S. But similar gene therapies are showing promise for other forms of genetic deafness. And researchers hope someday gene therapy may help with common types of hearing loss, like from aging and loud noise.

But some worry the focus on reversing deafness could further stigmatize deaf people.

“These kind of genetic therapies seem to reinforce this idea of deafness being a problem in need of eradication, and that the only solution for disabled people to fully assimilate into society is through a medical intervention,” says Jaipreet Virdi, who studies the history of medicine, technology and deafness at the University of Victoria in Canada and is herself deaf. “We’re saying: ‘Oh, deafness is a problem and we must fix that.'”

For her part, Sierra Smith is just thrilled she had this option for her son, even though the treatment has not yet fully restored his hearing.

“It’s incredible. Now he can hear me tell him how much I love him,” she says. “And he knows has a name now. And he’s discovering all these different sounds,” Smith says. “It’s so mind-blowing. I feel like I’m so blessed and I’m the luckiest mom on earth.”