Efficacy of recombinant activated factor VII vs. activated prothrombin complex concentrate for patients suffering from haemophilia complicated with inhibitors: a Bayesian meta-regression

Abstract

The optimal on-demand treatment of joint bleeds in haemophilia patients with inhibitors is a source of debate, with studies reporting various efficacy levels for different drugs and dosage regimens. To analyse, in a unified Bayesian meta-regression model, the published efficacy of recombinant activated factor VII (rFVIIa) and/or activated prothrombin complex concentrate (aPCC) as on-demand treatments for joint bleeds in haemophilia patients with inhibitors. A systematic search was carried out to identify studies reporting on dosage and efficacy of rFVIIa and aPCC in the treatment of joint bleeds in the target patient population. Data were abstracted and included in the model and adjusted for potential sources of heterogeneity. Pooled efficacy levels for typical rFVIIa and aPCC regimens were estimated. Seventeen studies, collectively reporting on >2000 joint bleeds, were included. Medication type combined with dosage was the only significant explanatory parameter. The model predicts that a typical regimen of 90 microg kg(-1) rFVII repeated every 3 h if needed results in cumulative joint bleed resolution of 66%, 88% and 95% after 12, 24 and 36 h, respectively. In comparison, a typical regimen of 75 IU kg(-1) aPCC repeated every 12 h if needed results in cumulative joint bleed resolution of 39%, 62% and 76%, respectively. These differences were statistically significant and were also robust in sensitivity analyses. This analysis suggests that a typical rFVIIa regimen will resolve joint bleeds more effectively than a typical aPCC regimen after 12, 24 and 36 h.