Retinal tissue partially restored in dry AMD stem cell trial

A study in the United States trialling a potential new treatment for dry age-related macular degeneration (AMD) has reported more encouraging early results, which researchers say demonstrates the condition is not irreversible.

Lineage Cell Therapeutics Inc has announced that retinal tissue has been partially restored in a patient taking part in early phase trials of OpRegen®, a retinal pigment epithelium (RPE) cell transplant therapy which is being developed to treat dry AMD. The trial sees RPE cells derived from stem cells injected under the retinas of patients with advanced dry AMD.

The company reported that a person with dry AMD who received an RPE cell transplant ‘showed substantial restoration of retinal tissue’. When the patient was assessed nine months later, the area of damage in the retina was around 25 per cent smaller than it was prior to receiving treatment. When examined again a further six months later, the damaged area had grown approximately 50 per cent slower than it had historically. The study also found the patient had ‘exhibited a consistent seven to ten letter improvement in their visual acuity for the past year’. So the treatment had rejuvenated some of the eye cells that were damaged but not dead and restored some vision, as well as slowing the progress of the disease.

RPE cells form a thin layer at the back of the eye which help to support and nourish the retina. Loss of these cells over time leads to dry AMD.

Lineage Cell Therapeutics Inc has previously reported five patients receiving the transplant had seen notable improvements in their vision from just 14 days after receiving treatment, which had been maintained 15 months later.

Commenting on the latest results, the company said its findings showed that dry AMD ‘is not an irreversible, degenerative condition and that some portion of diseased retinal tissue may be recoverable in atrophic end-stage disease patients.’