Sodium glucose co-transporter 2 inhibition is a novel mode of treatment for type 2 diabetes mellitus (T2DM). The sodium glucose co-transporter 2 inhibitor canagliflozin lowered blood glucose, blood pressure, and body weight, with increased risk of urogenital infections in Phase 2 studies. Effects on macrovascular complications of diabetes remain to be determined. CANVAS is a double-blind, placebo-controlled trial designed to evaluate the effects of canagliflozin on the risk of cardiovascular disease and to assess safety and tolerability in patients with inadequately controlled T2DM and increased cardiovascular risk. The first of 2 planned phases randomized 4,330 individuals to placebo, canagliflozin 100 or 300 mg (1:1:1) with planned follow-up of about 2 years to substantiate potential cardiovascular protection by assessing key biomarkers and to achieve initial safety objectives. By the end of mid-September 2012, a total of 7174 patient-years of follow-up were accrued. Mean baseline age was 62 years, duration of diabetes 13 years; hemoglobin A_1c 8.2%, fasting plasma glucose 9.3 mmol/L, and body mass index 32 kg/m². Of the participants, 34% are female and 57% had a history of atherosclerotic vascular disease. Participants will be followed up to achieve primary safety and tolerability objectives and to investigate secondary outcomes. The planned second phase will not be undertaken. CANVAS will define the effects of canagliflozin on biomarkers and provide data on cardiovascular safety against established regulatory parameters.