The cardiovascular safety of sitagliptin has been evaluated in TECOS ("Trial Evaluating Cardiovascular Outcomes with Sitagliptin"). TECOS recruited patients with type 2 diabetes and a history of cardiovascular disease who received, as add-on to their usual therapy, either sitagliptin (n = 7.257) or placebo (n = 7.266), with a median follow-up of 3 years. The primary cardiovascular outcome was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for unstable angina. Sitagliptin was noninferior to placebo for the primary composite cardiovascular outcome (hazard ratio, 0.98; 95% confidence interval, 0.88 to 1.09; P<0.001). Rates of hospitalization for heart failure did not differ between the two groups (hazard ratio, 1.00; 95% CI, 0.83 to 1.20; P=0.98). The cardiovascular safety of sitagliptin, which was already shown in meta-analyses of phase II-III randomised controlled trials and in observational cohort studies in real life, is now confirmed in the landmark prospective cardiovascular outcome study TECOS.