Eight children born with a “devastating” genetic disease in England became the first in the world to receive pioneering treatment to prevent them from going blind.
Doctors at Great Ormond Street Hospital in London are testing a drug they believe could save the sight of children with CLN2-type Batten disease. Brineura, already effective in animals, is given to four boys and four girls on a compassionate basis.
The breakthrough treatment works by restoring a “missing” enzyme that the nerves in the back of the eyes need to function. Clinicians and families hope that a body of evidence accumulating over the next year will allow the drug to be made more widely available to affected children around the world.
CLN2 disease is caused by a change in a gene responsible for the production of a vital enzyme in the nervous system. The enzyme recycles waste, and without it, waste accumulates. CLN2, which affects 50 children in the UK and hundreds around the world, causes seizures first and then a gradual decrease in their ability to walk, speak and see, as well as progressive dementia. The life expectancy is 10 to 12 years.
The Carroll family has been struck twice by CLN2: Amelia, eight, and her brother Ollie, 10, both have it. It’s too late to save Ollie’s sight, but Amelia has been selected for trial.
Their mother, Lucy, from Cheshire, said: “We have seen our son Ollie go blind, and now the same thing is starting to happen to Amelia. But we were given this chance, this hope. Saving the sight of a child would be amazing and would 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 just hope she can prove that this treatment works so that children in the future can have it in both eyes and it will save their sight. “
With Ollie turning 11 in January, Carroll is aware he may not have much longer to live. “We have learned to live each day like the last,” she said. “And create as many memories as possible – just spend as much time as possible with the kids as a family.”
The drug being tested is already being used to help prevent neurological deterioration in children with Batten disease. Brineura was first approved for use on the NHS in 2019 and is given directly to the brain through a regular infusion. It has been shown to restore enzyme activity and slow the onset of disability.
But although it is effective in preventing loss of movement and speech, brain perfusion does not prevent children from losing sight because it cannot reach the nerves in the eye. In the Great Ormond Street Hospital program, clinicians use the small amount of medicine that is left in the perfusion in the brain and inject it directly into the back of children’s eyes.
The eight patients – aged 4 to 10 – were chosen by doctors to test the treatment given under general anesthesia after it was found to be safe and effective in animals. Doctors treat one eye per child every two months, and after one year they will compare the difference in vision between the two eyes.
The trial was only made possible after a huge fundraising campaign by the families of children affected by the disease and the Batten Disease Family Association (BDFA). Together they have raised over £ 200,000, in hopes the lawsuit could be life-changing for 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 only four years old and nothing could have been more devastating. The brain infusions helped stabilize Kavy, but seeing his vision deteriorate over the years and make him lose confidence was very painful.
“Like so many other families of children with this terrible disease, we knew we had to do whatever we could and worked closely with the GOSH clinical team to help get this program started. We feel extremely lucky that Kavy has a chance to keep what little sight he has left; it means everything to us.
Dr Paul Gissen, Honorary Consultant in Pediatric Metabolic Diseases at Great Ormond Street Hospital, said: “Enzyme replacement therapy given to the brain has completely changed the lives of children with CLN2-type Batten disease, but it was difficult. to see their eyesight deteriorate even as their other physical symptoms are better controlled. The multidisciplinary team at GOSH worked hard to find a way to try and treat this and this was only possible through fundraising and the tireless work of the families of the patients.