A critical appraisal of the CURE trial: role of clopidogrel in non-ST-segment elevation acute coronary syndromes.

Background: A clinical study, the CURE trial, compared the use of clopidogrel/acetylsalicylic acid (ASA) to ASA alone in 12,562 patients with non-ST-segment elevation acute coronary syndromes (ACS). Results of the trial suggested a possible first-line role for the more expensive combination of clopidogrel/ASA.

Objective: To perform a critical appraisal of the CURE trial, to determine the efficacy and safety of the clopidogrel/ASA combination in the management of ACS patients and to describe the population most likely to benefit from this combination.

Methods: A critical appraisal of the CURE trial was conducted.

Results: The CURE trial was found to be of high quality (Jadad score 5/5). An absolute risk reduction (ARR) of 2.1% was seen for the clopidogrel/ASA combination for the first primary outcome (death from cardiovascular causes, non-fatal myocardial infarction (MI), or stroke), compared to ASA alone. A 2.3% ARR was seen for the clopidogrel/ASA combination for the second primary outcome, which included the first primary outcome or refractory ischemia. The clinical benefit appears to have mainly been driven by a reduction in the risk of non-fatal MI. A 1% absolute risk increase (ARI) was observed for major bleeding in the clopidogrel/ASA group. Also, 5.2% of subjects in the clopidogrel/ASA group discontinued their study medication for adverse events other than bleeding, thrombocytopenia or allergy, compared to 3.5% in the ASA group.

Conclusions: We established that the overall quality of the CURE trial was good. Compared to ASA, the clopidogrel/ASA combination reduces the risk of recurrent vascular ischemic events in non-ST elevation ACS patients. The main clinical benefit however appears to be limited to a reduction in the risk of non-fatal MI. This benefit needs to be interpreted in light of the associated increased bleeding risk. Given that the risk of MI is elevated in high-risk ACS patients, the benefit of clopidogrel/ASA combination is expected to outweigh the bleeding hazards for this population. As details of all adverse events were not reported, it was not possible to fully evaluate the safety of use of this intervention.