recombinant human coagulation factor VIIa Fc fusion protein

Recombinant human coagulation factor VIIa Fc fusion protein (notably SS109) is a long-acting bypassing agent developed for the treatment of hemophilia A or B in patients who have developed inhibitors against factor VIII or factor IX. The drug consists of recombinant activated factor VII (FVIIa) fused to the Fc region of human IgG1. This fusion utilizes the neonatal Fc receptor (FcRn) recycling pathway to significantly extend the plasma half-life of FVIIa, which typically has a very short duration of action (approximately 2 hours). Mechanistically, FVIIa bypasses the intrinsic pathway of the coagulation cascade by forming a complex with tissue factor to directly activate factor X, or by activating factor X on the surface of activated platelets at high concentrations. This promotes thrombin generation and clot formation, providing a therapeutic option for patients whose inhibitors render standard factor replacement therapy ineffective. SS109 is currently being evaluated in clinical trials to determine its safety, pharmacokinetics, and efficacy as a long-acting alternative to standard FVIIa products.

Other names

rhFVIIa-Fcrecombinant human coagulation factor VIIa-Fc fusion protein