Empagliflozin is an inhibitor of the sodium–glucose cotransporter 2, and can be used in patients with type 2 diabetes mellitus to reduce hyperglycaemia by increasing urinary glucose excretion. To determine the safety of this drug in patients at high cardiovascular risk, the EMPA-REG OUTCOME investigators randomly allocated 7,020 of these patients to receive 10 mg or 25 mg of empagliflozin or placebo once daily, in addition to standard care. Empagliflozin was associated with a significant reduction in the composite end point of cardiovascular outcomes and, in particular, in the rates of hospitalization for heart failure (35% relative risk reduction), cardiovascular death (38% relative risk reduction), and all-cause death (32% relative risk reduction). “Our trial,” conclude the investigators, “provides data to support the long-term use of empagliflozin, as well as strong evidence for a reduction in cardiovascular risk.”