Recombinant factor VIIa use in patients with the rarest forms of inherited coagulation-factor deficiencies: a study of cases from the www.haemostasis.com registry

Abstract

Rare inherited coagulation disorders (RICDs) with a prevalence of ≤1/1,000,000 include deficiencies in factor II, factor V, combined factor V/factor VIII, factor X, factor XI and factor XIII. These abnormalities are associated with spontaneous haemorrhage and excessive bleeding after surgery or trauma. Management is complicated by limited information and variations in biochemical characteristics and bleeding phenotypes. The independently managed international registry, http://www.haemostasis.com , was established to collect data on investigational use of activated recombinant factor VII (rFVIIa) in preventing or treating severe bleeding episodes. Patients suffering from the rarest forms of RICDs and receiving rFVIIa as treatment were identified from the http://www.haemostasis.com registry. Case providers were contacted to verify data and obtain consent for inclusion in this study. Eleven patients were identified; permission for inclusion was declined in two cases. The nine cases reported in this study included patients with factor II, factor V, combined factor V/factor VIII, combined factor V/von Willebrand’s disease, factor X, factor XI, factor XI with inhibitors and factor XIII deficiencies. The median individual dose of rFVIIa was 105.9 μg/kg body weight (range: 55–508 μg/kg), whereas the median total dose was 327.3 μg/kg body weight (range: 78.4–880 μg/kg). rFVIIa treatment was associated with a decrease, cessation or prevention of bleeding in eight cases; bleeding after trauma remained unchanged in one case of factor XIII deficiency. Positive pro-coagulatory responses were shown to occur at a wide range of anatomical sites. No deaths or rFVIIa-related adverse events were reported. In conclusion, this study suggests that rFVIIa has a favourable safety profile and that it may be used to treat or prevent haemorrhage in patients with RICDs.