The treatment of factor VIII inhibitors--a general overview

The management of patients with classic hemophilia who develop inhibitory antibodies against transfused factor VIII has been the frequent subject of international and national conferences. While treatment of such patients cannot be considered as standardized, several therapeutic approaches are currently available. These include the induction of immune tolerance, removal or eradication of inhibitory antibodies by immune adsorption and/or immune suppression, neutralization of the inhibitor by porcine factor VIII or high doses of human factor VIII, and bypassing of the inhibitor using recombinant factor VIIa or other bypassing agents. In addition to currently available therapeutic strategies, other approaches are under investigation, including the use of selected factor VIII peptides that block the inhibitor; the use of immunologically mute factor VIII products, for example a human-porcine factor VIII chimera not recognized by factor VIII inhibitors, and the use of anti-idiotypic antibodies. The ability to recognize those patients destined to develop inhibitors is also under active investigation.