A Randomized Crossover Study of High- and Standard-Dose Recombinant Factor VIIa for Treatment of Hemarthroses in Hemophiliacs with Inhibitors.

A multicenter randomized crossover trial was designed to compare efficacy, safety, feasibility and cost associated with standard- and high-dosages of rFVIIa for home treatment of hemarthroses in hemophiliacs with inhibitors. Enrolled patients were instructed to treat within 6 hours from the onset of bleeding 4 consecutive haemarthroses of ankles, knees or elbows either with the rFVIIa standard dose of 90 mcg/kg (repeated as necessary every 3 hours) or with a single high dose of 270 mcg/kg. Patients who did not achieve a success within 9 hours continued rFVIIa treatment with repeated standard doses. The response to treatment was assessed for up to 48 hours by patients/caregivers who reported on a visual analogic scale (VAS) graded from 0 to 100 the improvement in symptoms and also rated the response as effective, partially effective or ineffective. Success was defined a treatment rated as effective and VAS score ≥70 and failure a treatment rated as ineffective and VAS score ≤30, responses that did not fulfil these criteria being considered a partial response. Of 20 hemophiliacs with inhibitors enrolled (median age: 27 years), 18 treated 32 hemarthroses assigned to the standard- and 36 to the high-dose regimen during the study period of 18 months. Forty-eight hemarthroses (71%) occurred in target joints. Success rates for standard- and high-dose regimens were similar: 31% and 25% at 9 hours, 53% and 50% at 24 hours, 66% and 64% at 48 hours. Recurrence rates were identical (3%). The median number of rFVIIa boluses needed to achieve a successful course was 3 for the standard-dose and 1 for the high-dose regimen, and the median amount of rFVIIa used per successful course was identical (270 mcg/kg). Our results indicate that the use of a high-dose regimen with rFVIIa for home treatment of hemarthroses is effective, safe, does not imply an increased consumption of rFVIIa and requires the infusion of a smaller number of boluses. Its convenience is particularly relevant in cases with difficult venous access and in hemorrhages into target joints.