The mainstay of antiplatelet therapy for patients with acute coronary syndromes (ACS), including those undergoing early percutaneous coronary intervention (PCI), is the combination of aspirin and clopidogrel.1-3 Aspirin inhibits platelet thromboxane A2 production and platelet activation, and reduces the relative risk of recurrent ischaemic events in patients at high risk of vascular events by about 22% (absolute risk reduction [ARR], about 2%) at the expense of an increase in the odds of major bleeding events by about 60% (absolute risk increase [ARI], about 0.5%).1 Clopidogrel inhibits ADP-induced platelet activation by blocking the platelet P2Y12 receptor. When added to aspirin therapy in patients with ACS, it reduces the risk of recurrent ischaemic events by a further 20% (ARR, about 2.1%) at the expense of an increase in major bleeding events by approximately 38% (ARI, about 1%).2,3