Retinal progenitor cell transplantation offers a new approach to repairing damaged photoreceptors

By Irv Arons

At a Glance

Retinal progenitor cells (RPCs) can replicate many times and mature into many of the major retinal cell types
Clinical trials of RPCs for the repair of degenerated retinas are already underway
The results so far are promising: most patients exhibit improvement in their vision, with no safety issues reported to date
Other technologies – stem cell and gene therapy, electronic retinal implants and “retinal rejuvenation” – are also being investigated
Retinal degenerative diseases (RDDs) are a significant source of visual disability across the globe, with age-related macular degeneration (AMD) being the most common. A great number of RDDs have a genetic origin – like choroideremia, retinitis pigmentosa (RP), Leber congenital amaurosis and Stargardt disease, but irrespective of the cause, the treatment options available today are pretty limited.

Wet AMD might be treatable for a period with intravitreal VEGF inhibitors, but for many patients, this only postpones the inevitable. The loss of photoreceptor cells – as seen in the later stages of RP, dry AMD geographic atrophy, and the late stages of Stargardt disease – results in permanent visual loss.

There’s no approved therapy available yet that can slow or reverse the pathology. One potential way of doing this – placing retinal progenitor cells (RPCs) in the retina to replace the damaged cell types – is a therapeutic avenue that’s generating a lot of attention.