Experiences with recombinant factor VIIa in haemophiliacs.

Treatment of hemophiliacs with antibodies against factor VIII and factor IX is a matter of major concern in hemophilia care. Although a number of sophisticated methods for removal of antibodies have been designed, such procedures are suitable only in life-threatening situations since they are complicated and expensive.1, 2 Much effort has been focused on finding an agent capable of activating the final common pathway of the coagulation cascade, inducing hemostasis independent of the presence of factor VIII and factor IX. Such an agent should be hemostatically active, but also safe with regard to thromboembolic complications. Currently used prothrombin complex concentrates (PCC) or activated PCC (APCC) seem only to be active in about 50% of the bleeds.3, 4 Furthermore, thromboembolic complications are being reported following the use of PCC or APCC.5, 6 Activated factor VII (FVIIa) should be an attractive candidate since it is not proteolytically active until after having formed a complex with tissue factor or other phospholipids, thereby minimizing the risk of inducing a systemic activation of the coagulation system.