The coagulation cascade is a series of enzymatic reactions that turns inactive precursors into active factors. The end result of the cascade is the production of fibrin (factor Ia), a protein that binds platelets and other materials in a stable clot. The cascade has 2 initial pathways: the extrinsic (tissue factor-mediated) and the intrinsic (contact system-initiated). These 2 pathways converge to become the common pathway with the activation of factor X (see figure below).¹

Role of Antithrombin: The Coagulation Cascade

In addition to thrombin and factor Xa, AT inactivates other components of the coagulation cascade including factors IXa, XIa, XIIa, kallikrein, and the fibrinolytic plasmin.²

A Simplified Diagram of the Coagulation Cascade

References:

Escobar CE, Harmening DM, Joiner Maier DM, Simmons VL, Smith-Moore KM, Wyrick-Glatzel J. Introduction to hemostasis. In: Harmening DM, ed. Clinical Hematology and Fundamentals of Hemostasis. 4th ed. Philadelphia, PA: FA Davis Company; 2002:441-470.
Kottke-Marchant K, Duncan A. Antithrombin deficiency: issues in laboratory diagnosis. Arch Pathol Lab Med. 2002;126(11):1326-1336.

Important Safety Information

Thrombate III is indicated for the treatment of patients with hereditary antithrombin deficiency in connection with surgical or obstetrical procedures or when they suffer from thromboembolism.

In clinical studies with Thrombate III, the most common side effects were dizziness, chest tightness, nausea, and foul taste in the mouth.

The anticoagulant effect of heparin is enhanced by concurrent treatment with Thrombate III in patients with hereditary AT-III deficiency. Thus, in order to avoid bleeding, reduced dosage of heparin is recommended during treatment with Thrombate III.

Thrombate III is made from human plasma. Products made from human plasma may contain infectious agents, such as viruses, and, theoretically, the Creutzfeldt-Jakob disease (CJD) agent that can cause disease. There is also the possibility that unknown infectious agents may be present in such products.

Individuals who receive infusions of blood or blood plasma may develop signs and/or symptoms of some viral infections, particularly hepatitis C.

Please speak to your doctor and refer to Thrombate III Prescribing Information for full details.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch, or call 1-800-FDA-1088.