TORONTO — For the thousands of Canadians at risk of blindness, eight-year-old Sam is a beacon of hope.
He is the first Canadian to be treated with gene replacement therapy for a rare form of blindness which had left Sam unable to see sky on a cloudy day, and unable to make out shapes in the dark.
“Sometimes you have to walk in the night and I couldn’t see things and you bump into things,” Sam told CTV News.
He had to have lights on always, and had trouble seeing his shoes or objects on the floor. And the condition was progressive, meaning things would get worse as he grew older — a daunting prospect when there was no treatment available.
But now he can see cloudy skies, shoes and more. The best part of his improved vision, says Sam, are the stars at night.
“I never saw stars before,” he said. “And I also never saw airplanes flying at night.”
He was diagnosed after birth with a genetic disorder called retinitis pigmentosa, a form of genetic retinal degeneration resulting from mutations in the RPE65 gene.
“You lose perception of light,” Dr. Elise Heon, of Sick Kids Hospital, explained to CTV News. “You end up in darkness and [it’s] slowly progressive, it’s relentless, your visual field shrinks and shrinks and shrinks and shrinks.”
Retinitis pigmentosa (RP) affects between 1 in 3,500 to 1 in 4,000 Canadians, according to Fighting Blindness Canada. It actually refers to a group of disorders, as there are numerous versions of RP depending on which pair of genes are damaged. More than 64 genes have been identified by scientists as potentially having mutations that cause RP.
Now, Canada has approved the first-ever gene replacement therapy for this form of blindness. Sick Kids Hospital has 29 children in its program with this mutation. The drug can be used on children and adults with the condition, but the earlier it’s used, the more sight it will save, doctors believe.
“It’s a huge deal, because for these patients before, there’s no treatments,” Heon said.
She said she had recently met two patients, brothers, who were suffering the same problem as Sam, and for the first time, she was able to provide hope.
“They’re 10 years old, and they’re losing their vision,” she said. “If we do nothing, they’re just going, fine, they’ll just end up with no light reception. So for the first time [we were] able to say, well, actually we need to have a discussion. And it was just, it was priceless.”
The gene therapy, which goes by the brand name Luxturna, was developed in the U.S by the drug company Spark Therapeutics.
It works by placing a copy of the healthy gene into inactivated viruses, which are then injected into the retina. The gene then allows cells to produce the necessary protein to convert light into an electrical signal in the retina in order to provide healthy vision and prevent progression of the disease.
It is the first targeted gene therapy to be approved by Health Canada, which gave it the all-clear this week.
Back in 2019, Sam and his family travelled to the U.S to get the new gene therapy because it wasn’t available in Canada yet.
His mother, Sarah Banon, noticed changes quickly.
“About a week later, I noticed he could get dressed by [himself],” she said. “He could get his shoes on by himself, independently.”
His improvements have continued in the year since he first received the gene therapy.
“He is so much more confident,” his mother told CTV News. “Like getting dressed by himself, matching clothes, doesn’t have to have things enlarged. Being able to [see], even when it’s dark outside, no lights on and it is a cloudy day. He would have to, at school, keep the lights on.
“Now he is able to function as a normal child.”
With the approval of this gene therapy in Canada, doctors are hoping to be able to use it on more patients who qualify — and the earlier the better.
Dr. Peter Kertes, a vitreo-retinal surgeon and Ophthalmologist-in-Chief at Sunnybrook Health Sciences Centre, told CTV News that the approval of the therapy is “fantastic.”
“This is a huge breakthrough,” he said. “Most of the advances that we have in medicine are incremental. Every once in a while, once in a generation, something revolutionary like this comes along that really changes the course of therapy.”
Luxturna specifically treats individuals with biallelic mutations of the RPE65 gene — meaning they have mutations in that gene stemming from both parents — which manifests as either RP or Leber congenital amaurosis (LCA). It’s a very small patient group compared to the entirety of Canadians with inherited retinal diseases.
This may be just one gene therapy for one condition, but it will open to the door to this strategy being used in other scenarios, Kertes pointed out.
“This is the tip of the iceberg. I think this is a vector that will prove to be very effective and holds great promise,” he said. “I think many people who are living with blindness or facing blindness, have much to look forward to. I think we’re on the cusp of a revolution in this group of diseases.”
The company licensing the therapy, Novartis Pharmaceuticals Canada Inc., isn’t detailing the cost, but based on the price in the U.S it could top $1.1 million in Canada, making it among the most expensive drugs in the country.
The therapy is currently under review by both the Canadian Agency for Drugs and Technologies in Health (CADTH) and the Institut national d’excellence en santé et en services sociaux (INESSS).
Novartis said in a statement that they “look forward to receiving their recommendations following Health Canada’s approval.”
They said they are eager “to help eligible Canadians affected by this rare disease gain access to the first-ever gene replacement therapy as quickly as possible.”
The Patented Medicine Prices Review Board will be disclosing their new guidelines in terms of capping drug prices in an online media briefing this Thursday.
As this will likely be the first of many gene replacement therapies — with similarly high price tags — Ottawa and the provinces will have to make the decision on whether it will be covered by provincial health plans. The question is an ongoing ethical debate, with some saying that drug companies will only take advantage of it if governments show that they are willing to pay.
“Should it be the responsibility for the government to pay for any drug at any price?” Marc-André Gagnon, a researcher with Carleton University who looks into pharmaceutical policy, told CTV News. “The problem is, if we say yes to this question, you can be sure that the day after, all the drugs in the market will be asking for much higher prices.”
“It’s a very expensive drug,” Heon acknowledged.
However, she pointed out that this is a rare disease, and it’s “not a recurrent treatment.” It’s a one-time injection to the eyes.
“You treat both eyes and then that’s it,” she said.
“To be able to change someone’s life is quite a privilege. And to be able to prevent someone from going blind is a real privilege.”
For Sam and his mother, the gift of independence has been priceless.
“This is a story of hope,” his mother said. “A child told ‘it is what it is.’”
And now, when he looks up at night, he can see stars.
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