(±)-Clopidogrel hydrochloride is the hydrochloride salt of clopidogrel, which is a high affinity, selective and irreversible antagonist of the platelet purinergic P2Y12 receptor with IC50 value of 100 nM. It is used as a potent antithrombotic agent and requires bioactivation. It inhibits ADP-induced platelet aggregation ex vivo and functions as a prodrug. It enables its anti-aggregating activity via biotransformation to its active metabolite via CYP2C19 in the liver.