This article is more than 5 years old. Information may no longer be current.
Trial results released on effect of candesartan on diabetic retinopathy
Click Here to Manage Email Alerts
The angiotension receptor blocker candesartan has demonstrated the ability to significantly regress diabetic retinopathy in patients with type 2 diabetes, but the drug does not appear to significantly reduce the incidence in patients with type 1 diabetes, according to preliminary results from the DIRECT study program.
"Despite the fact that the trials did not meet the primary endpoints, the data show encouraging results for candesartan-treated patients with regards to reducing the incidence of retinopathy in type 1 diabetes patients and increasing the chance of regression in type 2 diabetes patients," Anne Katrin Sjølie, MD, chair of the DIRECT (Diabetic retinopathy candesartan trials) Steering Committee, said in a press release announcing the study results.
Investigators at 309 centers in 30 countries assessed the effect of candesartan cilexetil on the onset and progression of diabetic retinopathy among 5,321 diabetes patients in three double-blind, randomized, placebo-controlled clinical trials, each with a minimum duration of 4 years. Patients were randomly assigned to received candesartan in 16 mg doses that were titrated to 32 mg, or placebo.
Specifically, the DIRECT-Prevent 1 trial evaluated the effect of candesartan on the incidence of retinopathy among 1,421 normotensive, normoalbuminuric patients with type 1 diabetes. The DIRECT-Protect 1 trial assessed the effect of candesartan on retinopathy progression in 1,905 normotensive, normoalbuminuric patients with type 1 diabetes with existing diabetic retinopathy. The DIRECT-Protect 2 trial evaluated the effect of candesartan on the progression of existing retinopathy among 1,905 normoalbuminuric normotensive or hypertensive patients with type 2 diabetes.
The investigators found that candesartan had reduced the incidence of retinopathy in type 1 diabetes patients without retinopathy at baseline by 18% as measured by a two-step change on the ETDRS scale (P = .0508). However, the drug caused a 35% reduction in retinopathy incidence for a three-step change (P = .003), according to the release.
In type 1 diabetes patients with retinopathy at baseline, candesartan had no effect on progression.
When compared with placebo, candesartan reduced the risk of retinopathy progression by 13% in patients with type 2 diabetes, although the reduction was not significant.
However, compared with placebo, candesartan increased the regression rate of retinopathy by 34% in patients with type 2 diabetes (P = .009), the release said.
The results of the trials will be published in The Lancet.