Gene Therapy Restores Sight in Children with Ultra-Rare Retinal Dystrophy

Rare Daily Staff

Four young children with an ultra-rare genetic retinal dystrophy have gained improvements in sight following treatment with a new gene therapy, a study in the journal The Lancet reports.

The four children were born with a severe impairment to their sight due to a genetic deficiency that affects the AIPL1 gene. Those affected with the condition are born with only sufficient sight to distinguish between light and darkness. The gene defect causes the retinal cells to malfunction and die, with children affected being legally certified as blind from birth. The new treatment is designed to enable the retinal cells to work better and to survive longer.

The children were treated with a gene therapy developed and manufactured at UCL Institute of Ophthalmology and Moorfields Eye Hospital. MeiraGTx supported production, storage, quality assurance and released and supplied it for treatment under the genetic medicine company’s MSL.

The procedure to administer the treatment to the affected children took place at Great Ormond Street Hospital. The children were assessed in the NIHR Moorfields Clinical Research Facility, and the NIHR Moorfields Biomedical Research Centre provided infrastructure for the research.

The first four children received this novel therapy in one eye to minimize potential safety issues. All four experienced significant improvements in the treated eye over the following three to four years but lost sight in their untreated eye.

The outcomes of the new treatment show that gene therapy at an early age can dramatically improve sight for children with this condition – one that is rare and particularly severe. Successful gene therapy for another form of genetic blindness (RPE65 deficiency) has been available on the United Kingdom’s National Health Service since 2020. These new findings offer hope that children affected by both rare and more common forms of genetic blindness may in time also benefit from genetic medicine.

An additional seven children who were blind at birth as a result of AIPL1-associated severe retinal dystrophy have been treated in both of their eyes and have had similar results as the first four children with visual acuity in their treated eyes after four or more weeks follow treatment.

“We have, for the first time, an effective treatment for the most severe form of childhood blindness and a potential paradigm shift to treatment at the earliest stages of the disease,” said Michel Michaelides, professor of Ophthalmology at the UCL Institute of Ophthalmology and consultant retinal specialist at Moorfields Eye Hospital. “The outcomes for these children are hugely impressive and show the power of gene therapy to change lives.”