Prospective evaluation of treatment regimens, efficacy and safety of a recombinant factor VIII concentrate in haemophilia A: the German EffeKt study.

INTRODUCTION: Collecting clinical data under routine conditions remains important to monitor continuously efficacy and tolerability of an established product.

AIM: This prospective observational study aimed at evaluating efficacy and tolerability of full-length sucrose-formulated recombinant FVIII (rFVIII-FS; KOGENATE(®) Bayer/KOGENATE(®) FS) in routine use and analysing concomitant diseases and medication.

METHODS: Haemophilia A patients treated with rFVIII-FS were followed up for 24 or 36 months. Efficacy, tolerability, concomitant medication and diseases were assessed at yearly intervals.

RESULTS: Two hundred and twenty-one documented patients were mainly pretreated, predominantly with prophylaxis (74%). On study, 54 (31%) patients in the efficacy set (n = 174) documented regular prophylaxis, 91 patients (52.3%) failed to document their prescribed prophylactic infusions, 25 (14.4%) received on-demand treatment and four patients (2%) inhibitor adapted therapy. Patients on regular prophylaxis reported 8.4% of infusions for bleeding treatment and on-demand patients reported 55.3%. Young patients experienced mainly trauma-related bleedings and older patients reported spontaneous bleedings. Joint status was good overall. Median annual spontaneous joint bleeding rate in all groups was zero. A total of 79.0% of all bleedings were successfully treated with one or two infusions. Degenerative arthropathy and arterial hypertension were the most prominent concomitant diseases. Eighty-seven patients (40.5%) took at least one concomitant drug on study, mostly drugs for pain treatment related to haemophilic arthropathy. Two patients presented with positive inhibitor titres on study, one of them was a previously untreated patient and the other had a positive inhibitor history.

CONCLUSION: This study corroborates the tolerability and efficacy profile of rFVIII-FS.