One-quarter standard-dose ticagrelor better than standard-dose clopidogrel in Chinese patients with stable coronary artery disease: A randomized, single-blind, crossover clinical study

Abstract

Background: Ticagrelor has been demonstrated to provide a more rapid and powerful inhibition of platelet aggregation compared with clopidogrel in coronary artery disease (CAD) patients. In our previous study, we found that half-dose ticagrelor produced similar inhibitory effects on platelet aggregation as standard-dose ticagrelor and exerted significantly stronger effects than clopidogrel in Chinese patients with non-ST-elevation ACS. Therefore, we performed this study to observe the efficacy of one-quarter standard-dose ticagrelor in comparison to standard-dose clopidogrel in Chinese patients with stable CAD.

Methods: In a randomized, single-blind, crossover trial, 30 patients with stable CAD were randomized to one-quarter standard-dose ticagrelor (22.5mg BID for 7days) or standard-dose clopidogrel (75mg QD for 7days). Following a 2-week washout period, patients switched regimens. Light transmission aggregometry (LTA) and VerifyNow assay were used to measure platelet function.

Results: The platelet aggregation rate (PAgR) was obviously lower with ticagrelor than clopidogrel (17.70%±12.67% versus 27.63%±13.10%, P<0.05). The % inhibition levels in the ticagrelor group exhibited significantly greater than that in the clopidogrel group (65.33%±21.31% versus 36.23%±23.01%, P<0.01). PRU values in the ticagrelor group were dramatically lower than that in the clopidogrel group (87.03±51.38 versus 163.77±58.66, P<0.01). High-platelet reactivity (HPR) (≥208 PRU) was 0% with ticagrelor and 16.67% with clopidogrel.

Conclusions: One-quarter standard-dose ticagrelor provided greater degree of platelet inhibition than standard-dose clopidogrel in Chinese patients with stable CAD.

Keywords: Clopidogrel; Coronary artery disease; Platelet function tests; Ticagrelor.