Clopidogrel response variability

The mechanisms responsible for clopidogrel response variability are incompletely defined. Pharmacokinetic and pharmacodynamic differences in clopidogrel metabolism have been proposed to explain variable platelet inhibition. 

Gurbel PA. Clopidogrel response variability and drug resistance. Haematologica 2004 897 (suppl 7) 9-l I. 

Suboptimal platelet response to clopidogrel may be due to an increased number of platelet P2Y 2 receptors or polymorphism of platelet receptors. Genetic polymorphisms of platelet GPIIb/llla, GPIa/lla, or P2Y 2 receptors have been reported to affect platelet function and may influence dopidogrel response variability (103-105). Recently, it was reported that an increased percentage of patients with peripheral arterial disease have the P2Y 2 receptor H2 haplotype (104). However, in another study, the relation of this haplotype to clopidogrel responsiveness could not be demonstrated (105). Since the relation... 

Sankyo Co. Ltd. Tokyo, Japan) is a new thienopyridine derivative that produces more potent platelet inhibition, and a rapid onset of action. The latter properties may provide a superior alternative to clopidogrel, with less response variability and a decreased prevalence of nonresponsiveness (I I I). 

Gurbel PA, Bliden KR Hiatt BL, O Connor CM. Clopidogrel for coronary stenting response variability, drug resistance, and the effect of pretreatment platelet reactivity. Circulation 2003 107 2908-2913. 

Serebruany VL, Steinhubl SR, Berger PB, Malinin Al, Bhatt DL, Topol EJ, Variability in platelet responsiveness to clopidogrel among 544 individuals. J Am Coll Cardiol 2005 45 246-251. 

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