Candesartan Benefits Diabetes-Related Retinopathy
Yet studies indicate only early stages of existing diabetic retinopathy need apply
FRIDAY, Sept. 26 (HealthDay News) -- Patients with type 1 diabetes and no existing retinopathy are less likely to develop the condition if they are treated with candesartan, but the drug does not have a beneficial effect in patients who already have retinopathy, according to a report published online Sept. 26 in The Lancet. A second study indicates that candesartan can lead to improvement of retinopathy in patients with type 2 diabetes and mild to moderate retinopathy.
Nish Chaturvedi, M.D., of Imperial College Healthcare NHS Trust in London, U.K., and colleagues conducted two clinical trials across 309 centers worldwide, of normotensive, normoalbuminuric type 1 diabetes patients with and without retinopathy, randomized to treatment with candesartan or placebo, with the primary endpoints of incidence and progression of retinopathy. In the group without pre-existing retinopathy, 25 percent of the patients in the treatment group went on to develop the condition, versus 31 percent in the placebo group, the investigators found. However, in the pre-existing retinopathy group, progression occurred in 13 percent of both the treatment and placebo groups.
In the second study, Anne Katrin Sjolie, of Odense University Hospital in Denmark, and colleagues randomized 951 participants to candesartan and 954 to placebo with the primary endpoint of progression of retinopathy and secondary endpoint of regression. The researchers did not find any significant risk reduction for progression in patients on candesartan compared with those on placebo, however, regression was increased by 34 percent upon active treatment with an overall change towards less severe retinopathy by trial end observed in the candesartan group (odds ratio 1.17).
"Although the impression suggests overall beneficial effects of candesartan in reducing retinopathy in both type 1 and 2 diabetes, neither prespecified primary endpoint was reached in the two studies," according to the authors of an accompanying editorial. "An important take-home message is that only the early stages of existing diabetic retinopathy might have the potential to improve with candesartan treatment."
Both studies were funded by AstraZeneca and Takeda, and several of the study authors report financial ties to the companies.