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Factor IX (FIX)

CSL Behring · Phase 3 active Biologic

Factor IX is a vitamin K-dependent clotting factor that replaces deficient or dysfunctional Factor IX to restore the intrinsic coagulation pathway and enable normal blood clot formation.

Factor IX is a vitamin K-dependent clotting factor that replaces deficient or dysfunctional Factor IX to restore the intrinsic coagulation pathway and enable normal blood clot formation. Used for Hemophilia B (Factor IX deficiency) — prevention and treatment of bleeding episodes, Hemophilia B — perioperative management.

At a glance

Generic nameFactor IX (FIX)
SponsorCSL Behring
Drug classClotting factor replacement therapy
TargetFactor IX (coagulation factor IX)
ModalityBiologic
Therapeutic areaHematology
PhasePhase 3

Mechanism of action

Factor IX is a serine protease that functions as part of the tenase complex in the intrinsic coagulation cascade. By replacing missing or defective endogenous Factor IX, the drug restores the ability to generate thrombin and form stable fibrin clots. This is essential for patients with Factor IX deficiency (hemophilia B) who otherwise have impaired coagulation and are at risk of spontaneous or excessive bleeding.

Approved indications

Common side effects

Key clinical trials

Primary sources

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