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Warfarin (Coumadin)

University of Michigan · FDA-approved active Small molecule

Warfarin inhibits vitamin K-dependent clotting factors (II, VII, IX, X) by blocking the enzyme vitamin K epoxide reductase, thereby reducing the formation of blood clots.

Warfarin inhibits vitamin K-dependent clotting factors (II, VII, IX, X) by blocking the enzyme vitamin K epoxide reductase, thereby reducing the formation of blood clots. Used for Atrial fibrillation for stroke prevention, Venous thromboembolism (deep vein thrombosis and pulmonary embolism) treatment and prevention, Mechanical heart valve thromboprophylaxis.

At a glance

Generic nameWarfarin (Coumadin)
SponsorUniversity of Michigan
Drug classVitamin K antagonist (oral anticoagulant)
TargetVitamin K epoxide reductase (VKORC1)
ModalitySmall molecule
Therapeutic areaCardiovascular
PhaseFDA-approved

Mechanism of action

Warfarin acts as a vitamin K antagonist that prevents the carboxylation of vitamin K-dependent coagulation factors in the liver. This results in the production of inactive clotting factors, which prolongs the prothrombin time (PT) and reduces thrombus formation. The anticoagulant effect develops over 36–72 hours as existing clotting factors are depleted.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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