Coagulation factor IIa and Coagulation factor Xa (FIIa and FXa)

Coagulation factors IIa (thrombin) and Xa are pivotal serine proteases within the common pathway of the blood coagulation cascade. Factor Xa, once activated from its zymogen form, assembles into the prothrombinase complex to catalyze the conversion of prothrombin (Factor II) into thrombin (Factor IIa). Thrombin serves as the ultimate effector of the cascade, converting soluble fibrinogen into insoluble fibrin to form a stable blood clot, while also activating platelets and providing feedback amplification by activating upstream factors. Due to their central roles in thrombus formation, both factors are major therapeutic targets for anticoagulant drugs. Direct oral anticoagulants (DOACs) like rivaroxaban and apixaban target Factor Xa, while dabigatran targets thrombin, providing effective prevention and treatment for conditions such as venous thromboembolism and stroke in atrial fibrillation.

Other names

ThrombinActivated Factor IIActivated Factor XStuart-Prower factorF2aFXa

Direct or indirect inhibition of serine protease activity to prevent the conversion of prothrombin to thrombin (Xa inhibition) or fibrinogen to fibrin (IIa inhibition).