Evaluation of the Glycometabolic Effects of Ranolazine in Patients With and Without Diabetes Mellitus in the MERLIN-TIMI 36 Randomized Controlled Trial

BACKGROUND: Ranolazine is a novel antianginal shown in an exploratory analysis in patients with diabetes mellitus and chronic angina to be associated with a decline in hemoglobin A(1c) (HbA(1c)). We designed a prospective evaluation of the effect of ranolazine on hyperglycemia as part of a randomized, double-blind, placebo-controlled outcomes trial. METHODS AND RESULTS: We compared HbA(1c) (percentage) and the time to onset of a > or =1% increase in HbA(1c) among 4918 patients with acute coronary syndrome randomized to ranolazine or placebo in the MERLIN-TIMI 36 trial. Ranolazine significantly reduced HbA(1c) at 4 months compared with placebo (5.9% versus 6.2%; change from baseline, -0.30 versus -0.04; P or =1% increase in HbA(1c) (14.2% versus 20.6% at 1 year; hazard ratio, 0.63; 95% confidence interval, 0.51 to 0.77; P110 mg/dL or HbA(1c) > or =6% was reduced by ranolazine (31.8% versus 41.2%; hazard ratio, 0.68; 95% confidence interval, 0.53 to 0.88; P=0.003). Reported hypoglycemia did not increase with ranolazine (P=NS). CONCLUSIONS: Ranolazine significantly improved HbA(1c) and recurrent ischemia in patients with diabetes mellitus and reduced the incidence of increased HbA(1c) in those without evidence of previous hyperglycemia. The mechanism of this effect is under investigation.