Recombinant factor VIIa clotting factor concentrates (containing no human proteins) compared to concentrates derived from plasma to treat acute bleeds in haemophiliacs with inhibitors

Haemophilia is an inherited bleeding disorder caused by a deficiency of a clotting factor and is characterised by bleeding into the joints. It is treated by the injecting a drug containing the missing clotting factor into veins. In some individuals with haemophilia, this factor is seen by the body as a foreign protein when it is injected and the body produces an antibody (inhibitor) that destroys the factor. In this way these people become resistant to treatment. Once someone with haemophilia develops an inhibitor, they are treated to eradicate the antibody (immunotolerance induction) and for acute bleeding episodes. Treatment for bleeding episodes is with one of two available bypassing agents, recombinant activated factor VIIa (Novoseven) or human activated prothrombin complex concentrate (FEIBA). It is not known if one of these products is better than the other. We searched for trials comparing the effectiveness (time until bleeding stops, effect on joint motion, need for re-treatment) and safety of Novoseven and FEIBA in people with haemophilia with inhibitors during episodes of acute bleeding. We found two clinical trials comparing Novoseven and FEIBA. The trials did not show a difference in the effectiveness of the two products and both were equally safe in terms of tolerability and the absence of clotting complications. We conclude that both recombinant factor VIIa and plasma derived concentrates can be used to treat bleeds in individuals with haemophilia and inhibitors.