New treatment may save eyesight of children with ‘devastating’ Batten disease
Eight children born with a “devastating” genetic disease in England have become the first in the world to receive a pioneering treatment aimed at stopping them from going blind.
Doctors at Great Ormond Street hospital in London are trialling a drug they believe may save the eyesight of the children who have CLN2-type Batten disease. Brineura, already successful in animals, is being administered to four boys and four girls on a compassionate use basis.
The groundbreaking treatment works by restoring a “missing” enzyme that nerves in the back of the eyes need to function. Clinicians and families hope a body of evidence built up over the next year will allow the drug to be offered more widely to children affected around the world.
CLN2 disease is caused by a change in a gene responsible for producing a vital enzyme in the nervous system. The enzyme recycles waste materials, and without it, waste builds up. CLN2, which affects 50 children in the UK and hundreds worldwide, initially causes seizures, then a gradual decline in their ability to walk, speak and see, as well as progressive dementia. Life expectancy is 10 to 12 years.
The Carroll family have been struck twice by CLN2: eight-year-old Amelia and her 10-year-old brother, Ollie, both have it. It is too late to save Ollie’s sight but Amelia has been selected for the trial.
Their mother, Lucy, from Cheshire, said: “We have watched our son Ollie go blind, and now the same is starting to happen to Amelia. But we have been given this chance, this hope. To save a child’s sight would be incredible, and make such a big difference to Amelia’s quality of life.”
Carroll said “any vision” saved for Amelia would be “better than nothing”, adding: “We’re just hoping that she can prove this treatment does work so that children in the future can get it in both eyes and it will save their sight.”
With Ollie turning 11 in January, Carroll is conscious he may now not have long to live. “We’ve learned to live every day as the last,” she said. “And create as many memories as we can – just spend as much time as we can with the children together as a family.”
The drug being trialled is already used to help prevent neurological deterioration in children with Batten disease. Brineura was first approved for use on the NHS in 2019 and is administered directly into the brain by a regular infusion. It has been shown to restore enzyme activity and slow the onset of disability.
But although it is effective in preventing movement and speech loss, the brain infusion does not prevent children losing their sight because it cannot reach the nerves in the eye. In the programme at Great Ormond Street hospital, clinicians are using the tiny amount of the drug left over from the brain infusion and injecting it directly into the back of the eyes of the children.
The eight patients – aged between four and 10 – have been chosen by doctors to trial the treatment provided under general anaesthetic after it proved safe and effective in animals.
Doctors are treating one eye in each child every two months, and after a year they will compare the difference in vision between the two eyes.
The trial has been made possible only after a huge fundraising campaign led by the families of children affected by the disease and the Batten Disease Family Association (BDFA). Together, they have raised more than £200,000, with the hope the trial can change the lives of others.
A second child undergoing the new treatment is eight-year-old Londoner Kavyansh.
His father, Dr Rahul Dubey, said: “Kavy was diagnosed with CLN2 when he was just four years old and nothing
could have been more devastating. The brain infusions helped to stabilise Kavy but watching his vision deteriorate over these years and him lose confidence, has been most painful.
“Like so many other families of children with this awful disease, we knew we had to do everything we could and we worked closely with the clinical team at GOSH and help get this programme under way. We feel extremely lucky that Kavy has some chance to keep the little sight he has left; it means everything for us.”
Dr Paul Gissen, an honorary consultant in paediatric metabolic diseases at Great Ormond Street hospital, said: “The enzyme replacement therapy given into the brain has completely changed the lives of children with CLN2-type Batten disease for the better, but it has been difficult to watch their sight deteriorate even as their other physical symptoms are more controlled. The multi-disciplinary team at GOSH has been working hard to find a way to try to treat this and it’s only been possible thanks to the fundraising and tireless work of the patients’ families.”