Table 2.

ADP-induced platelet aggregation in four subjects treated with clopidogrel with and without PPI co-therapy

Medication	Subjects
	#1 (wt/wt)	#2 (wt/wt)	#3 (wt/*2)	#4 (wt/*2)
baseline	normal	normal	normal	normal
(day 0)	85 U	79 U	89 U	101 U
clopidogrel mono-therapy	inhibited	inhibited	normal	inhibited
(day 7)	42 U	16 U	97 U	31 U
clopidogrel and omeprazole	inhibited	inhibited	n.s.*	normal
taken together (day 14)	44 U	10 U		74 U
clopidogrel and omeprazole	n.s.*	n.s.*	n.s*	normal
intake separated (day 21)				67 U
clopidogrel and rabeprazole	n.s.*	n.s.*	n.s.*	inhibited
taken together (day 28)				43 U

The reference range of the test was 53-122 U.

Clopidogrel intake inhibits ADP-induced platelet aggregation in subjects showing the expected clopidogrel effect. Normal platelet function under clopidogrel mono-therapy represents a non-responder status. The normalization of platelet function by co-therapy with clopidogrel and PPI after platelet function is inhibited by clopidogrel mono-therapy indicates a pharmacologically relevant drug interaction.

*n.s., not studied, according to protocol.