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Prothrombin time

University Hospital, Strasbourg, France · FDA-approved active Biologic

Prothrombin time (PT) is a laboratory test that measures the time it takes for blood plasma to clot, reflecting the function of extrinsic and common coagulation pathway factors.

Prothrombin time (PT) is a laboratory test that measures the time it takes for blood plasma to clot, reflecting the function of extrinsic and common coagulation pathway factors. Used for Monitoring anticoagulation therapy with warfarin and vitamin K antagonists, Assessment of bleeding risk and coagulation disorders, Evaluation of liver function.

At a glance

Generic nameProthrombin time
SponsorUniversity Hospital, Strasbourg, France
ModalityBiologic
Therapeutic areaHematology/Coagulation Monitoring
PhaseFDA-approved

Mechanism of action

PT measures the activity of coagulation factors I, II, V, VII, and X by adding tissue factor and calcium to citrated plasma and timing clot formation. It is primarily used to monitor anticoagulation therapy with warfarin and other vitamin K antagonists, and to assess bleeding risk or liver function. The test is not a drug itself but rather a diagnostic assay used to guide therapeutic decisions.

Approved indications

Common side effects

No common side effects on file.

Key clinical trials

Primary sources

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

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