Conditions: Drug Action Increased
Keywords: Clopidogrel Aspirin Interaction
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 302
Healthy volunteers: no

Brief summary:
Clopidogrel and aspirin are commonly used in combination to prevent heart attacks and to prevent blockage of stents. Both clopidogrel and aspirin work by preventing platelets (sticky cells that circulate in the blood) from forming blood clots in the arteries supplying oxygen to the heart and in stents. The investigators hypothesize that aspirin 325mg compared with aspirin 81 mg will increase blood levels of the active metabolite of clopidogrel in patients with a history of coronary artery disease who receive a 600mg loading dose of clopidogrel.

Detailed description:
Eligible patients will be randomized to receive clopidogrel 600mg + aspirin 325mg (Group A) or clopidogrel 600mg + aspirin 81mg (Group B). Patients will be fasted for at least 8 hours prior to study drug administration. Blood samples will be collected at 1 hour after study drug administration for measurement of clopidogrel active metabolite levels and genotyping.

Arms:
arm 1: Clopidogrel 600 mg plus aspirin 325mg arm 2: Clopidogrel 600mg plus aspirin 81mg

Interventions: intervention 1: Clopidogrel intervention 2: Aspirin intervention 3: Aspirin
Intervention descriptions: intervention 1: 600mg (2 pills) intervention 2: 325mg (1 pill) intervention 3: 81mg (1 pill)

Protocol document: