Volkers P, et al. - Given that, the occurrence of IgG alloantibodies (inhibitors) that neutralize factor VIII (FVIII) activity represents a major complication of FVIII therapy in congenital haemophilia A, researchers compared the second-generation full-length product to third-generation full-length product and other recombinant FVIII (rFVIII) with respect to the associated risk of high-titre inhibitor development. The primary analysis cohort comprised 1109 previously untreated patients (PUPs) with severe haemophilia A who were treated from 1993 to 2013. For the third-generation rFVIII product vs the second-generation rFVIII product, the risk of high-titre inhibitor development was lower. In PUPs, a trend of an increased risk of inhibitor development for one recombinant product was evident, which shows that it might not be justified to extrapolate from one rFVIII product to other products.