Switching from clopidogrel to prasugrel in patients having coronary stent implantation

There are very few clinical data concerning the safety of switching from clopidogrel to prasugrel in patients undergoing coronary stenting. However, in the daily activity, clinicians face the decision of switching patients at high-risk of thrombotic events from clopidogrel to prasugrel. Thus, we sought to evaluate clinical events in patients undergoing coronary stent implantation and prasugrel therapy with (SWITCH group) or without (NAÏVE group) prior clopidogrel therapy. A total of 454 patients with stable or unstable coronary artery disease, aged 70 ± 10 years, underwent non-emergent stent implantation and received prasugrel therapy. Of these, 315 (69 %) patients received clopidogrel before switching to prasugrel therapy. In 239 patients with high residual platelet reactivity (HRPR) on clopidogrel, prasugrel decreased platelet aggregation from 72 ± 11 to 43 ± 16 % (p < 0.001). There was no difference in in-hospital major or minor TIMI bleeding (2.8 vs. 4.3 %; p = 0.411) between the SWITCH and NAÏVE groups as well as in mortality, acute stent thrombosis, reinfarction and stroke rates. At multivariable analysis, independent predictors of bleeding were female gender (OR 5.56 [1.41-19.88] p = 0.014) and chronic renal failure (OR 6.27 [1.59-21.65] p = 0.009), but switching therapy did not. This result was confirmed after switching propensity score adjustment (c-statistic 0.81; Hosmer-Lemeshow test p = 860). Switching from clopidogrel to prasugrel in patients undergoing non-emergent coronary stent implantation seems to be tolerated with no overt signs of increased bleeding.