ABSTRACT
BACKGROUND: In patients receiving aspirin, the optimal duration of clopidogrel therapy after drug-eluting stent (DES) implantation remains unclear. METHODS: This multicentre, randomized, double-blind, placebo-controlled trial tested the hypothesis that in patients undergoing DES implantation, 6 months of clopidogrel is non-inferior to 12 months in terms of clinical outcomes. At 6 months after DES implantation, patients on clopidogrel were randomly assigned to either a 6-month period of placebo or an additional 6-month period of clopidogrel. The primary endpoint was the composite of death, myocardial infarction, stent thrombosis, stroke, and thrombolysis in myocardial infarction major bleeding at 9 months after randomization. RESULTS: Owing to slow recruitment and low event rates, the trial was stopped prematurely after enrolment of 4005 of 6000 planned patients. Of 4000 patients included in the final analysis, 1997 received 6 months of clopidogrel and 2003 received 12 months. The primary endpoint occurred in 29 patients (1.5%) assigned to 6 months of clopidogrel and 32 patients (1.6%) assigned to 12 months, observed difference -0.1%, upper limit of one-sided 95% confidence interval (CI) 0.5%, limit of non-inferiority 2%, Pfor noninferiority <0.001. Stent thrombosis was observed in five patients (0.3%) assigned to 6 months of clopidogrel and three patients (0.2%) assigned to 12 months; hazard ratio (HR) 1.66, 95% CI: 0.40-6.96, P = 0.49. Thrombolysis in myocardial infarction major bleeding was observed in 4 patients (0.2%) assigned to 6 months clopidogrel and 5 patients (0.3%) assigned to 12 months; HR 0.80, 95% CI: 0.21-2.98, P = 0.74. CONCLUSIONS: In the present trial, characterized by low event rates, we did not observe a significant difference in net clinical outcome between 6 and 12 months of clopidogrel therapy after DES implantation. However, the results of the trial must be considered in view of its premature termination and lower than expected event rates. The trial is registered with ClinicalTrials.gov, Identifier: NCT00661206.
Subject(s)
Coronary Artery Disease/therapy , Drug-Eluting Stents , Platelet Aggregation Inhibitors/administration & dosage , Ticlopidine/analogs & derivatives , Aged , Clopidogrel , Coronary Artery Disease/mortality , Double-Blind Method , Drug Administration Schedule , Female , Graft Occlusion, Vascular/etiology , Graft Occlusion, Vascular/mortality , Hemorrhage/chemically induced , Hemorrhage/mortality , Humans , Male , Middle Aged , Myocardial Infarction/etiology , Myocardial Infarction/mortality , Percutaneous Coronary Intervention/methods , Percutaneous Coronary Intervention/mortality , Prosthesis Failure/etiology , Stroke/etiology , Stroke/mortality , Ticlopidine/administration & dosage , Treatment OutcomeABSTRACT
In acute coronary syndromes (ACS), a dual antiplatelet regimen with an adenosine diphosphate (ADP) receptor antagonist plus aspirin has become the cornerstone of treatment. The third-generation thienopyridine prasugrel and the cyclopentyl-triazolo-pyrimidine ticagrelor provide a greater, more rapid and consistent platelet inhibition compared to their predecessor clopidogrel. Based on their advantages over clopidogrel in two landmark studies, both drugs received a class I recommendation for their use in ACS patients with and without ST segment elevation. Due to differences in ACS populations and conditions investigated, the relative merits of ticagrelor versus prasugrel in the treatment of ACS patients with planned invasive strategy cannot be reliably estimated from independent trials. To date, no direct head-to-head comparison of ticagrelor and prasugrel in terms of clinical outcome exists. The aim of this multicenter, randomized, open-label trial is to assess whether ticagrelor is superior to prasugrel in ACS patients with planned invasive strategy.
