In a press release from early March 2021, cell therapy company CiRC Biosciences, Inc. (“CiRC”) shared that its chemically induced photoreceptor-like cells (CiPCs) received Orphan Drug designation from the FDA. The CiPCs are designed to treat patients with retinitis pigmentosa (RP), a group of genetic disorders which cause retinal degeneration. In a prior study, conducted in mice models of RP, CiPCs helped improve visual function and partially restored pupil reflex. Read the results of that study published in Nature.
Using CiRC’s novel and proprietary technology, the company chemically transdifferentiates fibroblasts, or connective tissue cells, into other cell forms. The company does this via a special chemical conversion process. Altogether, it takes under 2 weeks for CiRC to develop CiPCs. Through this reprogramming, CiPCs mimic retinal cells and enhance visual abilities. This is especially important for patients with RP. As of the time of this article, no FDA-approved therapies exist to restore vision loss in patients with RP. Thus, CiPCs could fulfill an important unmet need. Outside of RP, CiRC is also exploring CiPCs as a potential treatment for patients with geographic atrophy age-related macular degeneration (MD).
CiPCs received Orphan Drug designation from the FDA. This status is granted to drugs or biologics designed to address rare diseases. Overall, the FDA defines a “rare disease” as one which affects under 200,000 American citizens. Additionally, CiRC reaps some benefits from this designation: up to 7 years of market exclusivity following approval, tax credits, and fee waivers.
Retinitis Pigmentosa (RP)
Over 60 separate gene mutations are known to cause retinitis pigmentosa (RP), retinal diseases which cause progressive vision loss. RHO gene mutations account for up to 30% of diagnoses. As photoreceptor cells in the retina slowly degenerate, patients lose their vision. However, the severity and progression ultimately depend on which specific mutation is present. Patients may have autosomal dominant, autosomal recessive, or X-linked RP. In RP, either rods or cones in the eye may be affected. Typically, rods are affected first, causing a loss of night and peripheral vision. By the time cones are affected, patients often also have difficulty with perceiving color, central vision, and seeing details. By age 40, many patients are legally blind. So, altogether, symptoms include:
- Night blindness
- Loss of central and peripheral vision
- Difficulty seeing colors or details