The safety of pharmacologic options for the treatment of persons with hemophilia

INTRODUCTION: The mainstay of treatment of hemophilia A and B is the replacement of the congenitally deficient coagulation factor through the intravenous infusion of specific concentrates (factor VIII, FVIII, in hemophilia A; factor IX, FIX, in hemophilia B). Several commercial brands of FVIII or FIX products extracted from human plasma or engineered using recombinant DNA technology are available. AREAS COVERED: We analyze the safety aspects of plasma-derived and recombinant FVIII and FIX products licensed in Europe, focusing on their pathogen safety and inhibitor and thrombosis risks. The safety aspects of bypassing agents (i.e., activated prothrombin complex concentrates and recombinant activated factor VII) used for treatment of bleeding episodes in inhibitor patients will be also briefly discussed. EXPERT OPINION: The analysis of the published literature documents the high degree of safety from pathogen risk for both plasma-derived and recombinant products available for hemophilia treatment. The main threat to factor concentrate safety is represented by the development of neutralizing alloantibodies against the infused coagulation factor, which in hemophilia A seem to occur more frequently following the administration of recombinant than plasma-derived FVIII products. Great expectations are placed on newer products, particularly on those based upon mechanisms of action other than FVIII replacement.