Type of Factor VIII Replacement Product Does Not Affect Inhibitor Risk in Previously Untreated Hemophilia A Patients

Noting that a number of studies have explored the impact of the type of factor VIII replacement therapy on inhibitor development in hemophilia A patients with conflicting results, Italian investigators performed a systematic review and metaanalysis of published trials to evaluate new inhibitor rates in previously untreated patients (PUPs) with severe hemophilia A.

Data from a total of 800 patients enrolled in 25 quality-selected prospective studies published between 1990 and 2007 were included in this review. Overall, the inhibitor incidence rate did not differ significantly between recipients of plasma-derived and recombinant factor VIII concentrates (weighted means: 21%, 95% CI, 14%-30% vs. 27%, 95% CI, 21%-33%). Similarly, rates of high-titer inhibitors did not differ significantly between patients treated with plasma-derived (weighted means: 14%, 95% CI, 8%-25%) or recombinant factor VIII concentrates (weighted means: 16%, 95% CI, 13%-20%). The investigators concluded that the type of factor VIII product “does not seem to influence the inhibitor rate in PUPs with severe hemophilia A.”