Systematic review of the management of patients with haemophilia A and inhibitors.

The London Directorate of Health and Social Care Research and Development Group recently commissioned the School of Health and Related Research at the University of Sheffield to perform a systematic review of the management of patients with haemophilia A and inhibitors. The main areas of the review were the epidemiology of inhibitors, the role and effectiveness of immune tolerance induction, and the control of acute bleeding. In addition, an economic model of the different treatment strategies was constructed. Among the findings was that the overall prevalence of inhibitors in unselected haemophilic populations is 5-7%, with the cumulative inhibitor risk varying from 0% to 39%. The prevalence of inhibitors was inversely related to the size of the reported population. Immune tolerance induction was considered desirable, with evidence suggesting that the Bonn protocol may be more effective than either the Malmo or low-dose protocols. Immunosuppressive drug regimens on their own were ineffective. Activated prothrombin complex concentrates (aPCC) were more effective than non-aPCC. Recombinant activated factor VII was also effective, but there were no randomized trials comparing this agent with aPCC. Porcine factor VIII was highly effective in both treating acute bleeding episodes and preventing bleeding after surgery.