Randomized, prospective clinical trial of recombinant factor VIIa for secondary prophylaxis in hemophilia patients with inhibitors.

Background: Hemophilic patients with factor VIII (FVIII) and FIX inhibitors suffer from frequent bleeding episodes and reduced quality of life.

Objectives: To evaluate whether secondary prophylaxis with activated recombinant factor VII (rFVIIa) can safely and effectively reduce bleeding frequency as compared to conventional on-demand therapy.

Methods: Thirty-eight male patients entered a 3-month preprophylaxis period to confirm high baseline bleeding frequency (mean > or = 4 bleeds per month). Twenty-two patients were randomized 1:1 to receive daily rFVIIa prophylaxis with either 90 or 270 microg kg(-1) for 3 months, followed by a 3-month postprophylaxis period.

Results: Bleeding frequency was reduced by 45% and 59% during prophylaxis with 90 and 270 microg kg(-1), respectively (P < 0.0001); however, there was no significant difference detected between doses. The majority of this reduction was maintained during the postprophylaxis period. Although all types of bleed were similarly reduced, the effect was most pronounced for spontaneous joint bleeds. Patients reported significantly fewer hospital admissions and days absent from work/school during prophylaxis as compared to the preprophylaxis period. No thromboembolic events were reported during prophylaxis.

Conclusion: Clinically relevant reductions in bleeding frequency during prophylaxis as compared to conventional on-demand therapy were achieved without raising safety concerns. These results provide evidence for the concept of secondary rFVIIa prophylaxis in inhibitor patients with frequent bleeds.