Resistance to antiplatelet drugs: we don't even see the top of the iceberg!

http://eurheartjsupp.oxfordjournals.org/content/8/suppl_G/G53

http://onlinelibrary.wiley.com/doi/10.1111/j.1538-7836.2007.02498.x/epdf

What are the possible causes of this ADP platelet hyperreactivity?

Clopidogrel is a prodrug: only 15% of the administered drug is converted into active metabolites by the cytochrome P4509 enzymes (Fig. 2). Researchers have studied possible polymorphisms in the genes encoding these enzymes, and almost contemporaneously, several research groups have shown the role of polymorphism CYP2C19 * 2 in increasing the risk of platelet hyperreactivity and, especially, clinical events [9] and [10].

http://www.sciencedirect.com/science/article/pii/S2214762414000541