RetroSense Therapeutics in Ann Arbor, Michigan are pioneering a method of genetic manipulation that could give back sight to people affected by retinal degenerative conditions, including retinitis pigmentosa (RP) and dry macular degeneration (AMD).
Photoreceptors in the back of our eyes, often called rods and cones, send signals to our brain by way of the optic nerve. Retinal degenerative conditions like RP and AMD cause these photoreceptors to die, reducing our ability to see clearly, especially in darker environments. As these conditions progress, the symptoms worsen, eventually resulting in blindness.
By using gene therapy to approach this issue, RetroSense has been able to add a new photosensitivity gene to the cells in the retina, restoring the eye’s ability to detect and process light.
The process is complicated, though. More than 100 different gene defects contribute to RP, and it’s not currently possible to address and correct all of them. Instead RetroSense is attempting to “install” entirely new photoreceptors, which bypasses the defective genes entirely. This translates to an effective treatment for all sufferers of RP, no matter what the underlying genetic cause for their condition.
The most promising tool RetroSense currently has at its’ disposal is RST-001, which uses a photosensitivity gene called channelrhodopsin-2 to generate brand new photoreceptors within the retina, restoring sight to patients who have lost it to RP and AMD.
Through many animal tests, specifically in primates, the efficacy and safety of channelrhodopsin-2 has been thoroughly demonstrated, and has shown to be very effective in the restoration of photoreceptors lost to retinal degenerative conditions.
This innovative form of vision restoration was originally developed by Dr. Zhuo-Hua Pan at Wayne State University and Dr. Alex Dizhoor at Salus University.