11-year-old girl becomes first UK patient to get gene therapy for rare sight-loss condition
The treatment, which had only been performed on one other person in the world, involves injecting healthy copies of a gene directly into the eye
An 11-year-old girl has become the first UK patient to have innovative gene therapy for a rare condition that robs children of their sight.
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The treatment, which had only been performed on one other person in the world, involves injecting healthy copies of a gene directly into the eye.
Catherine L’Estrange, from North Acton in west London, is hopeful the move will allow her to continue one of her favourite hobbies – reading books.
If the therapy works, her sight will be stabilised or may even improve, according to the surgeon who treated her.
Catherine was diagnosed Bardet-Biedl syndrome (BBS) when she was just a baby.
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The condition is caused by mutations to one of 20 different genes and impacts around one in 100,000 births in the UK, leaving patients blind by their late teens or early 20s.
As well as vision loss, BBS can also cause kidney problems, learning difficulties and obesity, and patients sometimes have extra fingers or toes.
The gene therapy, developed by biotechnology company MeiraGTx, was given to Catherine as part of an hour-long procedure at St Helier Hospital in March.
Surgeons removed the jelly inside her eye and injected healthy copies of a gene into the retina, the light sensitive layer of tissue at the back of the eye. In people with BBS, small cells in the retina die, leading to blindness.
Neruban Kumaran, consultant eye surgeon at Epsom and St Helier University Hospitals NHS Trust, told the Press Association: “By giving a healthy copy of the gene, it helps save those cells, and the hope is to either stabilise or improve vision.”
Catherine said: “If this treatment works, it will help me to carry on seeing things around me, and most of all I will be able to carry on reading books, which is one of my favourite things to do.”
Only one other person - a 17-year-old girl from Canada - had received the treatment before Catherine. Her procedure took place at St Helier in August last year.
The parents of the girl, who wishes to remain anonymous, said: “This treatment has given our daughter a precious chance to preserve her vision, and we hope it will become a life-changing therapy for children with BBS10 all over the world.”
Since Catherine, the procedure has also been performed on one other younger child with BBS.
After having the therapy, patients are seen in clinic and have various sight tests, such as reading from a chart and identifying different shades of colours.
Mr Kumaran said some have already said their vision is better in dim light and the feedback so far has been positive, though it will take years before the full results are known.
He said: “There is a hope that it may improve vision slightly, but it’s difficult to say,”
“It’s not going to leave someone with perfect vision. But the hope is to stabilise and/or improve vision. Only time will tell."
“Early reports from the families have been very promising, and it gives us lots of hope. But in practice, it will take many years before we’re sure.”
Mr Kumaran is hopeful there will be other children out there eligible for the therapy, as well as babies who have not even been born yet.