Effect of Platelet Inhibition with Cangrelor during PCI on Ischemic Events

BACKGROUND: The intensity of antiplatelet therapy during percutaneous coronary intervention (PCI) is an important determinant of PCI-related ischemic complications. Cangrelor is a potent intravenous adenosine diphosphate (ADP)-receptor antagonist that acts rapidly and has quickly reversible effects. METHODS: In a double-blind, placebo-controlled trial, we randomly assigned 11,145 patients who were undergoing either urgent or elective PCI and were receiving guideline-recommended therapy to receive a bolus and infusion of cangrelor or to receive a loading dose of 600 mg or 300 mg of clopidogrel. The primary efficacy end point was a composite of death, myocardial infarction, ischemia-driven revascularization, or stent thrombosis at 48 hours after randomization; the key secondary end point was stent thrombosis at 48 hours. The primary safety end point was severe bleeding at 48 hours. RESULTS: The rate of the primary efficacy end point was 4.7% in the cangrelor group and 5.9% in the clopidogrel group (adjusted odds ratio with cangrelor, 0.78; 95% confidence interval CI, 0.66 to 0.93; P=0.005). The rate of the primary safety end point was 0.16% in the cangrelor group and 0.11% in the clopidogrel group (odds ratio, 1.50; 95% CI, 0.53 to 4.22; P=0.44). Stent thrombosis developed in 0.8% of the patients in the cangrelor group and in 1.4% in the clopidogrel group (odds ratio, 0.62; 95% CI, 0.43 to 0.90; P=0.01). The rates of adverse events related to the study treatment were low in both groups, though transient dyspnea occurred significantly more frequently with cangrelor than with clopidogrel (1.2% vs. 0.3%). The benefit from cangrelor with respect to the primary end point was consistent across multiple prespecified subgroups. CONCLUSIONS: Cangrelor significantly reduced the rate of ischemic events, including stent thrombosis, during PCI, with no significant increase in severe bleeding. (Funded by the Medicines Company; CHAMPION PHOENIX ClinicalTrials.gov number, NCT01156571.).