Clopidogrel (Plavix®, Iscover®) selectively and irreversibly inhibits adenosine diphosphate (ADP)-induced platelet aggregation. Long-term administration of clopidogrel was associated with a modest but statistically significant advantage over aspirin in reducing adverse cardiovascular outcomes in patients with established cardiovascular disease in the CAPRIE trial. In other large well designed multicentre trials, such as CURE, COMMIT and CLARITY-TIMI 28, the addition of clopidogrel to aspirin therapy improved outcomes in patients with acute coronary syndromes. However, some issues regarding the use of clopidogrel remain unresolved, such as the optimal loading dose in patients undergoing percutaneous coronary interventions (PCI) and the optimal treatment duration following drug-eluting intracoronary stent placement.
Results of several large randomised trials, therefore, have established clopidogrel as an effective and well tolerated antiplatelet agent for the secondary prevention of ischaemic events in patients with various cardiovascular conditions, including those with ischaemic stroke or acute coronary syndromes. In addition, treatment guidelines from the US and Europe acknowledge the importance of clopidogrel in contemporary cardiovascular medicine.