What Is Retinitis Pigmentosa? What Can I Do About RP?
There has been remarkable progress in treating retinitis pigmentosa (RP) over the past few years. While there is still no cure for most forms of RP, several new therapies are showing promise.
Gene therapy (most advanced)
- RPE65 mutation: An FDA-approved gene therapy already exists for people with RP caused by mutations in the RPE65 gene. This treatment can improve vision in eligible patients.
- Broader gene therapies: New treatments are being tested for people with many different genetic forms of RP, including a Phase 3 trial of OCU400, a “modifier gene therapy” designed to work across multiple RP mutations rather than just one. Top-line results are expected in 2027.
Optogenetic therapy
These treatments aim to make surviving retinal cells responsive to light, even after most photoreceptors have been lost.
- Several Phase 1/2 studies have reported encouraging safety and early signs of improved light perception and functional vision in some patients with advanced RP.
CRISPR gene editing
Gene-editing approaches are being developed to correct disease-causing mutations directly. These remain experimental, but they represent one of the most exciting long-term strategies.
Neuroprotective drugs
Several medications are being studied to slow the death of retinal cells. One of the largest ongoing studies is evaluating N-acetylcysteine (NAC) to determine whether it can slow disease progression.
Stem cell therapy
Researchers are transplanting retinal cells derived from stem cells to replace damaged photoreceptors. These treatments are still in early clinical trials but could eventually benefit patients regardless of the specific genetic mutation. Another area of promising research is the use of stem cells that are introduced into the eye to restore or replace the dying retinal cells. This exciting work is ongoing at a number of institutions throughout the world, including Dr. Henry Klassen at the Gavin Herbert Eye Institute, a Discovery Eye Foundation supported stem cell researcher.
Henry J. Klassen is one of the leading researchers developing stem cell therapy for retinitis pigmentosa (RP). Rather than replacing the defective gene, his approach aims to preserve and support the retina using retinal progenitor cells, potentially benefiting people with many different genetic forms of RP.
Still in clinical trials, Dr. Klassen co-founded jCyte, which developed jCell, an injectable therapy made from donated human retinal progenitor (immature retinal) cells. For more information visit jcyte.com
The treatment is relatively simple:
- The cells are injected into the vitreous (the gel inside the eye).
- The cells are not intended to permanently replace the retina.
- Instead, they release growth factors that help protect surviving photoreceptors and may improve how the retina functions.
One of the biggest advantages of jCell is that it may work regardless of the specific RP mutation. Since more than 100 different genes can cause RP, a treatment that isn’t mutation-specific could potentially help many more people than current gene therapies.
What this means today
If someone has RP, the most important next step is to determine which genetic mutation is causing it. That information determines eligibility for current treatments and clinical trials. Genetic testing has become a key part of RP care.