Comparison of prasugrel versus clopidogrel in Korean patients with acute myocardial infarction undergoing successful revascularization

Background Although there have been several reports that prasugrel can improve clinical outcomes, the efficacy and safety of prasugrel is unknown in Korean patients with acute myocardial infarction (AMI) undergoing successful revascularization. Methods A total of 4421 patients [637 patients were prescribed prasugrel (60/10 or 5 mg, loading/maintenance dose) and 3784 patients clopidogrel (600 or 300/75 mg)] with AMI undergoing successful revascularization were enrolled from the core clinical cohort of Korea Acute Myocardial Infarction Registry-National Institute of Health. Results After propensity score matching (637 pairs), there were no significant differences in baseline clinical and procedural characteristics and in-hospital medications between the two groups. The primary efficacy endpoint, defined as the composite of cardiac death, MI, stroke, or target vessel revascularization at 6 months showed no significant difference between prasugrel and clopidogrel (2.4% vs. 2.9%, p = 0.593). Also, no difference was observed in the composite of cardiac death, MI, or stroke during hospitalization between two groups (0.8% vs. 0.9%, p = 0.762). However, the incidence of in-hospital Thrombolysis in Myocardial Infarction (TIMI) major or minor bleeding was significantly higher in prasugrel compared with clopidogrel (5.3% vs. 2.7%, p = 0.015). In multivariate linear regression analysis, trans-femoral intervention, use of glycoprotein IIb/IIIa inhibitors, use of calcium channel blocker, and use of prasugrel were independent predictors of in-hospital TIMI major or minor bleeding [odds ratio (OR) = 6.918; 95% confidence interval (CI) = 2.453–19.510, OR = 2.577; 95% CI = 1.406–4.724, OR = 4.016; 95% CI = 1.382–11.668, OR = 2.022; 95% CI = 1.101–3.714]. Conclusions Our study shows that the recommended dose of prasugrel had significantly higher in-hospital bleeding complications without reducing ischemic events compared with clopidogrel. However, further large-scale, long-term, randomized clinical trials are required to accurately assess the efficacy and safety of prasgurel and to find out the optimal dose for Korean AMI patients.