Patients who have had an acute coronary syndrome (ACS) are at high risk of recurrent cardiovascular events, particularly patients whose LDL-cholesterol (LDL-C) levels remain elevated despite receiving high-intensity statin therapy. The ODYSSEY OUTCOMES trial now shows that treating these patients with alirocumab, a human monoclonal antibody against PCSK9, improves their cardiovascular outcomes. A total of 18,924 patients with a previous ACS who were receiving statins at high-intensity or maximum-tolerated dose were randomly assigned to receive alirocumab or placebo every 2 weeks, with the alirocumab dose adjusted to a target LDL-C level of 25–50 mg/dl. The incidence of the primary end point (a composite of death from coronary heart disease, nonfatal myocardial infarction, fatal or nonfatal ischaemic stroke or unstable angina requiring hospitalization) was lower with alirocumab than with placebo (HR 0.85, 95% CI 0.78–0.93, P < 0.001), with those patients with baseline LDL-C levels ≥100 mg/dl having the greatest absolute risk reduction with alirocumab therapy.