Utilization of recombinant activated factor VII in southern Ontario in 85 patients with and without haemophilia

Abstract

Recombinant activated factor VII (rFVIIa) is licensed for the treatment of bleeding in individuals with haemophilia and inhibitors. The use of rFVIIa appears to be increasing, and an increase in unlicensed use is suspected. There are currently few data about the specific indications for its use. The aim of this study was to describe the patterns of utilization of rFVIIa. We performed a retrospective cohort study using rFVIIa infusion data collected prospectively and clinical data collected retrospectively. Patients were identified using a tracking system designed to account for use of all coagulation factor concentrates issued in southern Ontario. Between 1 January 2001 and 31 December 2005, 85 patients received rFVIIa. 1164 infusions were given (8246.4 mg). Haemophilia patients with inhibitors accounted for 82.9% of rFVIIa infused and represented 8.2% of patients. The total amount of rFVIIa used increased each year from 2001 to 2004 and then decreased in 2005. The total number of infusions of rFVIIa administered annually increased. Both on-label and off-label use of rFVIIa increased. The number of patients with haemophilia receiving rFVIIa remained small and constant. The number of patients receiving rFVIIa for off-label indications increased markedly. Most rFVIIa infusions were given for licensed indications; however, these infusions represented <10% of patients treated. Overall, the utilization of rFVIIa is increasing, mostly for approved indications; however, the number of patients being prescribed rFVIIa for off-label indications has increased. The tracking system used in this study is a valuable tool to describe ongoing utilization patterns of rFVIIa.

Recombinant activated factor VII in the treatment of non‐haemophilia patients: physician under‐reporting of thromboembolic adverse events

“…Our study shows a consistent trend of increasing off‐label rFVIIa usage, both in the amount administered and in the number of patients receiving rFVIIa (Fig. 2) in keeping with previous retrospective studies (MacLaren et al , 2005; Ganguly et al , 2006; Webert et al , 2007; Heller et al , 2008; Isbister et al , 2008). The number of patients who receive it for on‐label indications remained relatively low, albeit the dosage amounts varied widely from 9·6 to 907·2 mg.…”

“…Monitoring and reporting adverse drug reactions such as TAEs for rFVIIa is important for several reasons. First, its off-label utilization has rapidly increased and exceeds the number of patients receiving it for Ôon-labelÕ indications reported in several retrospective studies (MacLaren et al, 2005;Ganguly et al, 2006;Webert et al, 2007;Heller et al, 2008;Isbister et al, 2008). Second, its safety, including potential TAEs, has not been conclusively determined in nonhaemophilia populations even in randomized controlled trials (OÕConnell et al, 2006;Stanworth et al, 2007;Hsia et al, 2008).…”

“…Third, at approximately $1 US per microgram, it is expensive (Goodnough et al, 2004;Ganguly et al, 2006). In Canada in 2005, a single injection in an 80-kg person receiving 7Á2 mg or 90 mg kg 21 was estimated to cost between $6622Á56 and $8240Á04 (Webert et al, 2007). Thus, increasing usage in large non-haemophilia populations will have significant economic consequences.…”

Recombinant Factor VIIa: An Assessment of Evidence Regarding Its Efficacy and Safety in the Off-Label Setting

“…Several other studies have reported off-label use to similar degrees. 37,38,[45][46][47][48] We and others at our own institution recently completed a retrospective study of off-label rFVIIa usage patterns throughout the United States as part of a comparative effectiveness review for the Agency for Healthcare Research and Quality. 49 We found that, in 2008 (the most recent year of our analysis), 97% of inpatient uses of rFVIIa were off-label.…”