Blood
-
Multicenter Study
A sudden increase in factor VIII inhibitor development in multitransfused hemophilia A patients in The Netherlands. Dutch Hemophilia Study Group.
The development of antibodies to factor VIII (inhibitors) in response to clotting-factor concentrates administration in hemophilia is common during the first few years of treatment but rare in multitransfused patients. We have investigated the possible association of a recently introduced factor VIII concentrate (Factor VIII CPS-P) in The Netherlands with the occurrence of inhibitors. To this effect, we conducted two studies. ⋯ In a prospective extension of the study, with a second inhibitor measurement after 3 months, we found that one additional inhibitor had developed during 52.5 patient-years of Factor VIII CPS-P use. In conclusion, there has been a sudden increase in the frequency of inhibitor patients, for a large part among multitransfused patients. It seems more than likely that this increase is associated with the introduction of a new factor VIII concentrate in The Netherlands.(ABSTRACT TRUNCATED AT 400 WORDS)