Ticagrelor versus clopidogrel in Asian patients with acute coronary syndrome: A retrospective analysis from the Platelet Inhibition and Patient Outcomes (PLATO) Trial

Background In the PLATO trial, ticagrelor was superior to clopidogrel in reducing cardiovascular events among patients with acute coronary syndrome (ACS) at the expense of increased nonfatal bleeding. Because Asian patients, when compared with non-Asian patients, are believed to be more susceptible to bleeding, we evaluated the effects of ticagrelor compared with clopidogrel in Asian (n = 1,106) and non-Asian (n = 17,515) patients with acute coronary syndrome enrolled in the PLATO study. Methods and Results Interaction between Asian/non-Asian and primary efficacy end point (a composite of vascular death, myocardial infarction, and stroke) and net clinical benefit (composite of primary efficacy end point and coronary artery bypass graft [CABG] surgery or non-CABG-related major bleeding) were evaluated with a Cox proportional hazards model. Baseline demographics and comorbidities were different between Asians and non-Asians. The overall cardiovascular event rates were higher in Asians, but bleeding rates were similar. Despite these observed differences, the effects of ticagrelor versus clopidogrel were not significantly different between Asians and non-Asians with respect to the primary efficacy outcome (hazard ratio for Asians vs non-Asians, 0.84 [95% CI 0.61-1.17] vs 0.85 [95% CI 0.77-0.93], P =.974), net clinical benefit (0.85 [95% CI 0.65-1.11] vs 0.93 [95% CI 0.86-0.99], P =.521), or individual efficacy end points. There was no significant interaction for bleeding (PLATO major bleeding, 1.02 [95% CI 0.70-1.49] vs 1.04 [95% CI 0.95-1.14], P =.938) and other related adverse events with ticagrelor compared with clopidogrel between Asians and non-Asians. Conclusions We observed consistency of effects in Asian patients receiving ticagrelor and clopidogrel in the PLATO study. The relatively modest number of Asian patients in this analysis supports further investigation of larger cohorts to confirm our observations.