Factor VIII is an X-linked gene product that combines with
factor IXa in the presence of phospholipids and calcium, which then activates factor X.
The coagulation factor IX precursor contains coagulation
factor IXa light chain and heavy chain.
It complexes with tissue factor to promote the conversion of factor IX to
factor IXa, factor X to factor Xa, and prothrombin to thrombin--the key parts of the coagulation cascade.
Hemlibra is a bispecific factor IXa- and factor X-directed antibody designed to bring together
factor IXa and factor X, proteins required to activate the natural coagulation cascade and restore the blood clotting process for hemophilia A patients.