Foundation Funding Developer of "Slimy" Gene Therapy for Restoring Sight

February 02, 2012

Image of lab equipment

The secret to reversing blindness may lie in the DNA of pond scum — blue-green algae, to be precise — and the Foundation is providing a $250,000 grant to RetroSense Therapeutics, the developer of a treatment that delivers algal genes to the retina for restoring vision. RetroSense is hoping to launch a clinical trial of the gene therapy in two to four years, and the Foundation may invest additional money as certain milestones are met.

RetroSense’s genetic treatment is delivered to retinal ganglion cells, which survive long after rods and cones, the cells that normally provide vision, are lost to advanced retinal degenerations like retinitis pigmentosa and macular degeneration. The treatment contains copies of an algal gene called channelrhodospin-2, which make the ganglion cells light-sensitive. Normally, ganglion cells don’t provide vision; rather they help fine-tune the visual information generated by rods and cones.

“This field of research, known as optogenetics, is a very promising and creative approach to restoring vision in people with severe vision loss or complete blindness,” says Dr. Stephen Rose, the Foundation’s chief research officer. “RetroSense has outstanding technology, and it has achieved impressive results in lab studies. We are pleased to support the company in its effort to move the treatment into a clinical trial.”

One big advantage of optogenetic treatments, including RetroSense’s, is that, because they are independent of the genetic defects causing disease, they will likely work for a variety of retinal degenerations. “It is exciting to support a therapeutic approach that has the potential to benefit many people,” Dr. Rose says.

RetroSense has demonstrated that its treatment restores vision in mice with highly degenerated retinas. Seeking FDA authorization for a Phase I clinical trial, the company will perform additional studies to confirm the therapy’s safety and effectiveness. Because there is a large body of published scientific literature reporting on the success of optogenetics for vision restoration, RetroSense is optimistic about its timeframe for moving into the clinic.

Also, the company’s gene therapy uses an adeno-associated virus, or AAV, for delivering the therapeutic gene to the cells of the retina. The technology has performed well thus far in vision-restoring clinical trials of gene therapy for people with Leber congenital amaurosis. More than 40 people have been successfully treated in those studies.

The Foundation is also funding an optogenetic therapy project to revive cone cells — the cells in the retina that provide color and central vision. That effort is being led by Dr. José-Alain Sahel, director of the Foundation-funded Paris Research Center for the Study of Retina Degenerative Diseases, and Dr. Botond Roska of the Friedrich Miescher Institute for Biomedical Research in Switzerland.