Bioequivalence and Bioavailability Forum

Dear Rahul
Unchanged clopidogrel has no effect on platelet aggregation. It is converted mainly to the inactive metabolite and to a less degree to the active thiol metabolite. This active metabolite irreversibly inhibits platelet aggregation. No validated analytical method exists to measure concentrations of the active metabolite after a 75 mg single dose reliably. According to the SPC of Plavix clopidogrel can be given independently from food, since the efficacy is not affected. This information is also based on pharmacokinetic properties of the inactive metabolite only, which is bioequivalent under fed and fasted conditions. The bioavailability of unchanged clopidogrel is strongly increased by food.
McEwen J, Strauch G, Perles P, Pritchard G, Moreland TE, Necciari J, Dickinson JP: Clopidogrel Bioavailability: Absence of influence of food or antiacids. Seminars in Thrombosis and Hemostasis. 1999;25(2):47-50
Nirogi RVS, Kandikere VN, Mudigonda K: Effect of food on Bioavailability of a single oral dose of clopidogrel in healthy male subjects. Arzneim.-Forsch./Drug Res. 2006;56(11):735-739
I hope this helps
Kind regards
Dan