Randomized Comparisons of Double-Dose Clopidogrel or Adjunctive Cilostazol Versus Standard Dual Antiplatelet in Patients With High Posttreatment Platelet Reactivity

Background: Patients undergoing percutaneous coronary intervention react differently to antiplatelet drugs. Those with low responsiveness to clopidogrel have a higher risk of cardiac ischemic events. The goal of this study is to conduct a head-to-head comparison of the safety and effectiveness of intensified antiplatelet therapies (either double-dose clopidogrel [DOUBLE] or adjunctive cilostazol [TRIPLE]) and conventional strategy (STANDARD) in patients after percutaneous coronary intervention. Methods: In this single-center, randomized, controlled trial, we used thromboelastography, a platelet function test, to select 1078 patients undergoing percutaneous coronary intervention at high thrombotic risk and compared the intensified antiplatelet therapies with standard antiplatelet therapy. The primary outcome was the incidence of major adverse cardiac and cerebrovascular events at 18 months after percutaneous coronary intervention, defined as a composite of all-cause death, myocardial infarction, target vessel revascularization, or stroke. Bleeding Academic Research Consortium defined bleeding complications (types 1, 2, 3, or 5) were the safety end points. Results: The primary end point occurred in 52 patients (14.4%) in the STANDARD group, 38 patients (10.6%) in the DOUBLE group, and 30 patients (8.5%) in the TRIPLE group (hazard ratio, 0.720; 95% confidence interval, 0.474–1.094, DOUBLE versus STANDARD; hazard ratio, 0.550; 95% confidence interval, 0.349–0.866, TRIPLE versus STANDARD). No significant difference in the rates of major bleeding (Bleeding Academic Research Consortium grade≥3) was found in the DOUBLE group (3.34% versus 1.93% in STANDARD, P =0.133) and the TRIPLE group (2.53% versus 1.93% in STANDARD, P =0.240). The rate of Bleeding Academic Research Consortium–defined minor bleeding increased in the DOUBLE group (27.4% versus 20.3% in STANDARD, P =0.031), but not in the TRIPLE group (23.6% versus 20.3% in STANDARD, P =0.146). Conclusions: In patients with low responsiveness to clopidogrel, as measured by thromboelastography, the intensified antiplatelet strategies with adjunctive use of cilostazol significantly improved the clinical outcomes without increasing the risk of major bleeding. Decreased trend of negative outcomes could be observed in patients with double dosage of clopidogrel, but the difference was not significant. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT01779401.