A UK research company is planning a large clinical trial of stem cell therapy to reduce or halt the deterioration of vision people with retinitis pigmentosa (RP) experience for next year.

ReNeuron is currently undergoing a small trial of its retinal stem cell therapy with six patients that is reported to be showing good progress.

The therapy uses human stem cells – transformed into young retinal cells – that are injected into the eyes of patients who have RP.

It is hoped that the therapy will be able to reduce or even halt the deterioration in vision experienced by people with the degenerative disease.

So far, six patients have received the injections and researchers are steadily increasing the dose of cells that the patients receive.

Julian Howell, ReNeuron chief medical officer, told Optometry Today: “We have been very pleased with the progress (although) this part of the study is time consuming as we assess each patient for a number of weeks before moving to the new dose level.”

“So far we have been able to increase the dose of cells without any problems,” he said.

“We are exploring (measurements)relevant to improving the lives of patients with RP, and this ranges from central visual acuity, peripheral vision, light sensitivity and the ability to see in lower light levels.”

The patients who receive the treatment this year will also have their visual function rigorously assessed.

Mr Howell said if the large clinical trial in 2018 was successful it could enable ReNeuron to seek regulatory approval for the therapy to be offered to patients

“We are obviously very hopeful of developing a product that will make a significant improvement to the lives of patients with RP.”