Gene therapy improves vision in children with genetic condition

The effect of gene therapy in four children with AIPL1-associated severe retinal dystrophy has been described in The Lancet.

Researchers from Moorfields Eye Hospital and the UCL Institute of Ophthalmology reported that gene therapy resulted in improvements in visual acuity and functional vision, as well as some protection against progressive retinal deterioration.

The therapy was developed by scientists at University College London’s Wolfson Gene Therapy Unit and produced, stored, quality-assured and dispensed by MeiraGTx.

Moorfields Eye Hospital

Gene therapy participant, Jace, with his mother, DJ, photographed in London

The four children recruited to the study all had severe retinal dystrophy associated with deficiencies in the AIPL1 gene. Their vision at the beginning of the study was limited to light perception.

As the condition is very rare, the first four children identified to receive the novel intervention were from overseas. The procedure to administer the treatment took place at Great Ormond Street Hospital.

Gene therapy was performed in one eye in each child. The researchers found that in the two children who were able to comply with testing, an objective test of visual acuity confirmed improvements in visual function.

In three of the children, structural lamination of the outer retina was better preserved in the treated eye than in the untreated eye. In all four children, retinal thickness appeared better preserved in the treated eye compared to the untreated eye.

The treated eye of one child developed cystoid macular oedema. No other safety concerns were identified.

Jace, from Connecticut in the US, is one of the children who received treatment. His mother, DJ, described the improvements she saw in Jace following gene therapy.

“After the operation, Jace was immediately spinning, dancing and making the nurses laugh. He started to respond to the TV and phone within a few weeks of surgery and, within six months, could recognise and name his favourite cars from several metres away,” DJ shared.

Jace’s father, Brendan, shared his gratitude for the care his son received.

“When first offered the chance to participate, we wanted to give him everything we could, for him to successfully navigate the world. We also understood the huge implications for future research, and how participating could help others. It has been a phenomenally positive experience, and the results are nothing short of spectacular,” he highlighted.

Professor Michel Michaelides, a consultant retinal specialist at Moorfields Eye Hospital, described the gene therapy as a “potential paradigm shift.”

“The outcomes for these children are hugely impressive and show the power of gene therapy to change lives,” he said.