Scientists develop promising new treatment to prevent blindness from retinal disease

Millions of people around the world live with retinal diseases that progressively steal their sight. Age-related macular degeneration, diabetic retinopathy, and related disorders of the retina share a common problem: abnormal overgrowth of new blood vessels in the eye, a process called neovascularization. These rogue vessels damage the tissue and lead to vision loss that current treatments often cannot stop.

For the past fifteen years, doctors have relied on a class of drugs that block a protein called VEGF, which triggers the growth of these unwanted blood vessels. These medications have helped many patients, but they don't work for everyone, and they carry potential safety concerns. The treatment gap has been real and persistent—some people simply don't respond well to anti-VEGF therapy, and their vision continues to decline despite the best available options.

Researchers at Scripps Research Institute have now published findings in the Proceedings of the National Academy of Sciences describing a different approach entirely. Instead of blocking VEGF, they tested a fragment of a protein called CITED2, which works by dampening the activity of genes that are normally activated in retinal cells under low-oxygen conditions. When they injected this CITED2 fragment directly into the eyes of mice with retinal disease, something promising happened: the abnormal blood vessel growth was significantly reduced.

But the real distinction emerged in what the treatment preserved. Standard anti-VEGF drugs like aflibercept do reduce harmful neovascularization, but they also destroy healthy capillaries in the retina—a side effect researchers call vaso-obliteration. The CITED2 fragment, by contrast, not only suppressed the abnormal vessels but also allowed healthy capillaries to survive and even regenerate. When the team combined a lower dose of aflibercept with the CITED2 fragment, the results improved further: strong reduction in harmful vessel growth while maintaining and restoring the capillaries the eye needs to function.

The distinction matters because it suggests a treatment that works on a different biological principle than what has dominated the field for the past decade and a half. For patients who have not responded to current drugs, or who have suffered side effects, this represents a genuinely new option. The researchers expressed enthusiasm about the findings in their animal model and acknowledged the clinical need they are trying to address.

The next step is development toward human trials. The team plans to continue refining the CITED2-based approach with the goal of eventually testing it in people. That work remains ahead, and the path from mouse model to approved therapy is long and uncertain. But for the millions living with progressive retinal disease, the possibility of a treatment that works differently—one that might preserve what remains of their vision rather than simply slowing its loss—represents a meaningful shift in how researchers are thinking about the problem.