Levodopa for Diabetic Retinopathy

(TESDR Trial)

This trial tests whether levodopa can slow changes in the blood vessels of the eyes in people with diabetes. Researchers aim to determine if this treatment can benefit those with specific delays in their eye's electrical activity, detectable through a simple eye test. Participants will receive either Sinemet CR (which contains levodopa), a placebo (a pill with no active ingredients), or be part of a follow-up group. This trial may suit people with diabetes who have noticeable eye changes and have not received certain eye treatments in the past year. As an Early Phase 1 trial, this research focuses on understanding how the treatment works in people, offering participants a chance to contribute to groundbreaking research.

The trial does not specify if you need to stop taking your current medications, but you cannot have had anti-VEGF or steroid treatments in the last 12 months.

Research has shown that Sinemet CR, a combination of levodopa and carbidopa, can improve eye function in people with diabetes. Previous studies demonstrated significant benefits from short-term use, with improvements persisting even after treatment stopped.

Side effects occur less frequently when carbidopa is combined with levodopa. Carbidopa reduces side effects by lowering harmful dopamine levels in the body. This combination is already approved for other conditions, so its safety is well understood.

Most treatments for diabetic retinopathy focus on managing symptoms and slowing progression through laser surgery, injections, or anti-VEGF medications. But Sinemet CR, a combination of carbidopa and levodopa, works differently by potentially restoring visual function through its unique action on dopamine pathways in the retina. Researchers are excited because this approach could not only stop disease progression but also improve vision, offering a dual benefit that current treatments don't provide.

Research has shown that Sinemet CR, which contains levodopa, may improve eye health in people with diabetes. One study found that taking levodopa for a short time led to noticeable improvements in eye function after just two weeks, with benefits lasting several years. Another study suggested that levodopa might address early signs of diabetic retinopathy. Levodopa effectively reaches both the eyes and the brain, supporting its potential in treating eye changes due to diabetes. In this trial, participants will receive either Sinemet CR or a placebo to evaluate its effectiveness in slowing down diabetes-related eye changes.¹³⁴⁵⁶