Advertisement

Contact Person

Dr. Elinor Switzer

Managing Editor

Phone: +49 (0)711 - 2 29 87 63
Fax: +49 (0)711 - 2 29 87 65
send an Email


Archive

Clopidogrel and warfarin: absence of interaction in patients receiving long-term anticoagulant therapy for non-valvular atrial fibrillation

Journal: Thrombosis and Haemostasis
ISSN: 0340-6245
Issue: 2003: 89/5 (May) pp. 771-950
Pages: 842-846

Clopidogrel and warfarin: absence of interaction in patients receiving long-term anticoagulant therapy for non-valvular atrial fibrillation

Christer Lidell1, Lars-Erik Svedberg2, Peter Lindell3, Stellan Bandh4, Bernhard Job5, Lars Wallentin1
1Department of Cardiology, Uppsala University Hospital, 2Department of Medicine, Bollnäs Hospital, 3Department of Cardiology, Huddinge Hospital, 4Department of Cardiology, Västeras Hospital, Sweden, 5Sanofi-Synthélabo Recherche, Chilly-Mazarin, France

Summary

The effect of concomitantly administered clopidogrel on anticoagulation status was investigated in patients receiving longterm warfarin therapy. Forty-three patients with non-valvular atrial fibrillation who were receiving long-term warfarin and had a stable international normalized ratio (INR) between 2 and 3 were randomly assigned to clopidogrel 75 mg daily or placebo for 8 days (Days 1-8). INR (primary endpoint) and plasma levels of warfarin enantiomers (secondary endpoint) were evaluated at Days 3, 6, 9, 13 and 22. Mean INR remained extremely stable in the clopidogrel group, the maximum percentage change from baseline being 0.6% at Day 6. Plasma levels of R- and S-warfarin also remained very stable in those receiving clopidogrel. No serious adverse events, premature discontinuations of study drug or bleeding occurred with clopidogrel. In conclusion, the stable anticoagulation status of patients receiving long-term warfarin therapy is unaffected by concomitant administration of clopidogrel 75 mg daily.