Clopidogrel has been evaluated in clinical trials that included cardiovascular patients with different risk levels for a cardiovascular event. We reviewed the results of the
Clopidogrel vs
Aspirin in Patients at Risk of Ischemic Events (CAPRIE) and
Clopidogrel in
Unstable Angina to Prevent Recurrent Events (CURE) trials, with special emphasis on comparing the outcomes in high-risk patients with those of the total populations in the trials. The results in the high-risk subgroups and total populations were compared by recording total event rates, absolute risk reduction, relative risk reduction, and number needed to treat. In the CAPRIE trial, the efficacy of
clopidogrel was compared with
acetylsalicylic acid (ASA) in the following subgroups: total population, previous coronary bypass surgery, history of more than 1 ischemic event, multiple vascular beds involvement, diabetes, and
hypercholesterolemia. In the CURE trial, the combination of
clopidogrel and ASA was compared with ASA alone. The results in the CURE study were compared in patients who did and did not have a coronary intervention procedure, in patients with different levels of risk based on the Thrombolysis in
Myocardial Infarction score and in patients with and without a history of a revascularization procedure. High-risk subgroups of patients participating in the CAPRIE and CURE studies were more responsive to the beneficial effects of
clopidogrel compared with the study population as a whole. High-risk groups in the CAPRIE and CURE studies would be expected to derive enhanced benefit from treatment with
clopidogrel over that achieved by ASA.