An investigational drug could offer a new way to prevent or slow vision-threatening damage caused by diabetic retinopathy. Results published today in Science Translational Medicine show promise for danegaptide, an oral small molecule drug designed to protect the blood vessels of the retina from damage caused by high blood glucose, offering a simpler alternative to current medication.

“Managing diabetic eye disease before irreversible damage occurs has long been constrained by the burden of invasive injections,” said Matthew Campbell, PhD, chair of neurovascular genetics at Trinity College Dublin and senior author of the study. “Our findings demonstrate that a simple oral pill can effectively target and repair the inner blood-retina barrier. This potentially offers a non-invasive, preventive path forward that could protect vision in both eyes simultaneously, long before severe sight loss takes hold.”

Diabetic retinopathy is one of the leading causes of vision loss among working-age adults, affecting around 30% of people with diabetes. Non-proliferative diabetic retinopathy (NPDR) accounts for the majority of diabetic retinopathy cases and can progress over time to more advanced disease, potentially causing permanent sight loss.

Current treatments for NPDR, including anti-VEGF injections delivered directly into the eye, are generally used when the disease has progressed to stages where significant retinal damage or swelling is already present. The need for repeated eye injections can also make early intervention difficult.

Danegaptide is being developed by Breye Therapeutics with the goal of protecting the retinal blood vessels before more severe damage develops. The drug targets cell–cell connections that help maintain the integrity of retinal blood vessels, with the aim of preventing the leakage and breakdown associated with diabetic retinopathy.

In preclinical studies, oral danegaptide rapidly reduced blood-vessel leakage, prevented breakdown of the inner blood-retina barrier and reversed retinal swelling, with comparable effects to those seen with injectable therapies in the experimental models.

Campbell and colleagues also examined the drug in an early-stage clinical trial involving 24 people with NPDR. Oral danegaptide was reported to be safe and well tolerated, with 55% of participants showing early signs of biological activity including reductions in retinal leakage, decreased central retinal thickness, and resolution of intraretinal fluid cysts.

The findings build on earlier Phase Ib results presented by Breye in February 2026. That multicenter, open-label study was conducted at 11 sites across the U.K., Germany and the U.S. and assessed safety, tolerability, pharmacokinetics and early biological activity in patients with NPDR and associated macular edema.

So far, danegaptide has been evaluated in more than 500 clinical trial participants, showing a favorable safety profile. Breye Therapeutics is now preparing for a larger Phase II trial in NPDR, targeting clinical proof-of-concept by 2028.

“The data from this study validate a major paradigm shift in retinal care,” said Pete Adamson, chief scientific officer of Breye Therapeutics. “By proving that an oral therapy like danegaptide can directly protect the inner blood-retina barrier, we are opening the door to early, non-invasive intervention for NPDR. The successful Phase Ib results provide a very strong foundation for larger Phase II clinical trials to evaluate long-term efficacy.”