ABCA4-associated retinopathies are a group of conditions that cause progressive macular degeneration and vision loss due to ABCA4 mutations. Stargardt disease, cone-rod dystrophy type 3 (CORD3), and retinitis pigmentosa 19 are all examples of ABCA4-associated retinopathies. Right now, doctors estimate that more than 40,000 people in the United States are living with these conditions; many of these individuals have no access to treatments designed to target the underlying disease directly. That’s why biotechnology company Ocugen, Inc. is developing OCU410ST (AAV5-hRORA), a gene therapy that would address the cause of these conditions rather than just treating the symptoms.
Treatment Development for ABCA4-Associated Retinopathies
In a recent Ocugen news release, the company reported that the U.S. Food and Drug Administration (FDA) granted Orphan Drug designation to OCU410ST for the treatment of ABCA4-associated retinopathies. This designation is given to drugs or biologics intended to treat, prevent, or diagnose rare conditions, which are defined as those which impact less than 200,000 people nationwide. Designed to incentivize drug developers to work within the rare disease space, this designation also comes with benefits such as fee waivers, increased regulatory assistance, seven years of market exclusivity upon approval, and tax credits.
OCU410ST works by delivering a gene that encodes for the production of human retinoic acid receptor-related orphan receptor alpha. It helps to produce a protein in the retina that clears away all-trans-retinal aldehyde from photoreceptor cells. When this product builds up in the cells, it causes damage and vision loss. Through this gene therapy, Ocugen aims to stop vision loss and preserve vision health. In the future, the company hopes to hold clinical studies to further evaluate the therapy’s safety, efficacy, and tolerability.
A Brief Stargardt Disease Overview
Stargardt disease is a type of ABCA4-associated retinopathy. This inherited retinal disorder causes vision loss that often begins in childhood or adolescence. While people with Stargardt disease often do not go blind, they do lose vision to 20/200 or worse. The progression and speed differs from person to person. Stargardt disease occurs when ABCA4 mutations cause cones and rods in the eyes to die. Symptoms include vision loss in both eyes, bright light sensitivity, color blindness, difficulty moving from light to dark environments, hazy or dark spots in the center of vision, and peripheral vision loss. There are no treatments or cures.
