Ruboxistaurin reduces risk of vision loss in diabetic patients

Compared with placebo, ruboxistaurin mesylate (proposed brand name, Arxxant, Eli Lilly and Co.) reduces the risk of sustained moderate vision loss by 41% in patients with moderate-to-severe nonproliferative diabetic retinopathy, according to pooled data from two 3-year phase III trials. Eli Lilly and Co. presented the findings at the American Diabetes Association's annual scientific sessions recently.

Investigators analyzed data from the PKC-DRS and PKC-DRS2 studies. The combined analyses followed 813 patients treated once a day with 32 mg of ruboxistaurin (n = 412) or placebo (n = 401). The two multicenter, randomized, placebo-controlled, double-masked, phase III trials were similar in design and implementation. Sustained moderate vision loss was defined as a three-line loss that was sustained for at least 6 months.

Researchers found that vision loss occurred in 6.1% of patients taking ruboxistaurin compared with 10.2% of patients taking the placebo, equaling a 41% relative risk reduction (p = 0.011) over 3 years.

"These data are exciting because they show that ruboxistaurin has the potential to be the first oral therapy to reduce the risk of vision loss specifically caused by diabetic retinopathy," said lead investigator Lloyd Paul Aiello, MD, PhD, director, Beetham Eye Institute & Section on Eye Research, Joslin Diabetes Center, and associate professor of ophthalmology, Harvard Medical School, Boston. "This could be an important clinical development for the millions of people around the world who are at risk for vision loss caused by this serious disease."

A separate data analysis of 11 studies (totaling 2,804 patients) found that ruboxistaurin was generally well tolerated and had an overall adverse event profile, as well as a serious adverse event profile, similar to placebo in patients who had at least one diabetic microvascular complication.