Comparison of Clinical Efficacy and Safety of Clopidogrel Resinate With Clopidogrel Bisulfate in Patients Undergoing Percutaneous Coronary Intervention

A new polymeric salt form of clopidogrel, clopidogrel resinate (CR), is a resinate complex of the (+)-clopidogrel optical isomer wherein the (+)-clopidogrel isomer binds to a water-soluble cation exchange resin via sulfonic acid groups. CR was approved for marketing by the Korean Food and Drug Administration based on a Phase I bioequivalence study. However, no data are available regarding its impact on adverse clinical outcomes in patients undergoing percutaneous coronary intervention (PCI). Clopidogrel bisulfate (CB) was used exclusively from January 2004 through April 2010, after which CR was exclusively administered from May 2010 through September 2011, in 8 centers. We categorized the overall population (N = 10,487) into two groups according to the prescribed clopidogrel type: CB (n = 9,127) or CR (n = 1,360). To minimize the covariate imbalance and confounding in comparing CB and CR, we used a multivariable Cox proportional hazard regression model and the propensity score (PS) method to identify a 1:1 matched cohort (n = 2,470). We compared cumulative adverse outcomes during a 1-year follow-up after PCI in the overall population and in the PS-matched cohort. In the overall population, there is no difference in the 1-year cumulative event rates between the two groups (CB : CR) : composite of any death, nonfatal myocardial infarction or stroke (6.0 % vs. 6.0 %, adjusted HR, 0.82; 95 % CI, 0.61-1.11, p = 0.57), stent thrombosis (0.4 % vs. 0.2 %; adjusted HR, 0.40; 95 % CI, 0.09-1.72, p = 0.31), and bleeding (0.9 % vs. 0.6 %; adjusted HR, 0.67; 95 % CI, 0.28-1.58, p = 0.22). In the PS-matched cohort, the overall findings were consistent. In this large real-world PCI population, CR was as effective and as safe as CB in preventing adverse clinical outcomes.