In a latest development, the first patient has been treated with ReNeuron’s cell therapy candidate for retinitis pigmentosa (RP) in a first-in-human U.S. clinical trial. ReNeuron Group plc is a leading UK-based stem cell therapy development company. The procedure, involving a single injection of human retinal progenitor cells (hRPCs) under the retina, was conducted at Massachusetts Eye and Ear in Boston.

The patient was discharged from the hospital on the same day. ReNeuron has demonstrated that its hRPCs improve visual acuity in preclinical models of retinal degeneration and, uniquely, the cells appear to protect the host retina from further degeneration as well as engraft into the retina itself and differentiate into the photoreceptor cell types that are lost as a result of the disease.

These putative mechanisms of action suggest that ReNeuron’s cell therapy candidate could potentially treat any of the specific genetic variants of retinitis pigmentosa rather than, as is the case with gene therapy approaches, being restricted to the targeting of one particular genetic cause of disease.

Retinis Pigmentosa is a group of inherited diseases of the retina that gradually leads to reduction in vision and is one of the most common inherited causes of blindness among people aged between 20 and 60. The phase I/II trial is an open-label one and the FDA has granted fast track designation to the company's hPRC programme. Speaking on the development Dr Somdutt Prasad, one of the top retinal specialists and eye doctor of Kolkata said, "Although further studies will be needed before this becomes available to patient's outside clinical trials, this new therapy looks like the most promising one we have seen yet for Retinitis Pigmentosa sufferers."