Coagulation Factor XIIa-Mediated Activation of Coagulation Factor XI

Coagulation factor XIIa (FXIIa) is the activated form of coagulation factor XII (FXII, also known as Hageman factor), a serine protease that plays a central role in the initiation of the intrinsic pathway of blood coagulation. FXII is converted to FXIIa upon contact with negatively charged surfaces. Once activated, FXIIa catalyzes several downstream reactions, most notably the activation of coagulation factor XI (FXI) to its active form, FXIa. This activation is a key step in thrombin generation and subsequent fibrin formation. While FXII deficiency does not typically lead to bleeding, FXIIa and FXIa are attractive targets for antithrombotic therapies due to their role in pathological thrombosis and inflammation.

Inhibition of FXIIa activity or FXIIa-FXI interaction