Models of prophylaxis.

Long-term, continuous prophylaxis for haemophilia began at a modest scale during the 1950s and 1960s in Sweden and The Netherlands. In the face of high cost and impediments to the performance of longitudinal, well-designed studies, it was decades before prophylaxis was considered to be the best practice in countries that could afford the cost. In 2007 and 2011, the only prospective randomized studies ever performed confirmed what large cohort studies in Europe had long since shown. Today, focus is on when to start prophylaxis, dosing and when/if to stop. Retrospective comparisons of the Swedish and Dutch cohorts, where different strategies have been used, indicate that a costly, high-dose regimen improves outcome, but not dramatically. A prospective comparison is now underway. Treatment, clinical outcome, clotting factor consumption and socioeconomic parameters will be compared between the two strategies. Results are expected to provide greater insight into the long-term consequences of the different prophylactic treatment strategies. The economic justification for prophylaxis has been addressed in several studies with varying results. While the majority (implicitly) suggest that prophylaxis is not cost effective at conventional willingness to pay for additional units in health thresholds, their results vary markedly. Closer inspection suggests that the primary reasons results differ include different definitions of prophylaxis, clotting factor price, discount rates, choice of outcome measures and time horizon.