Complications associated with the treatment of haemophiliacs with inhibitors

To examine the safety profile of products used to treat inhibitor patients unresponsive to factor VIII, a review of published clinical experience was performed. The products evaluated were activated prothrombin complex concentrates (aPCCs), such as AUTOPLEX® T, porcine factor VIII and recombinant activated factor VII (rVIIa). Safety characteristics included potential for transmission of infectious agents, anamnesis, thrombogenicity, thrombocytopenia and allergic reactions. While viral transmission has been virtually eliminated, the risk is theoretically higher with plasma-derived products such as aPCC and porcine factor VIII than with rVIIa, although contamination of cultured cells is a concern. Anamnesis occurs with aPCCs and porcine factor VIII, and may induce resistance to further therapy with porcine factor VIII. Thrombosis and disseminated intravascular coagulation are very infrequently reported in patients exposed to aPCCs and rVIIa, and never with porcine factor VIII. The latter is occasionally associated with thrombocytopenia, but this uncommonly limits treatment with this agent. Lastly, allergic reactions occur with about equal frequency with all products, but anaphylaxis is mainly a concern after administration of porcine factor VIII. In conclusion, products currently available are reasonably safe. Considerations such as efficacy, availability, ease of administration and cost must also be considered in making treatment choices.