Response to the Letter by Spurling and Colleagues

While we acknowledge that some (not all) guidelines recommend 50 U/kg, this recommendation is based upon limited data and neither dose has been assessed in clinical trials and been proven safe or efficacious or is approved by authorities for this indication. Prior studies comparing low- and high-dose 4F-PCC for reversal of oral FXai have demonstrated 25 U/kg is used more frequently in routine practice, and neither hemostatic effectiveness nor in-hospital mortality appear to be superior with the 50 U/kg dose versus 25 U/kg [3, 4]. While our propensity score-weighted comparative study design is not a substitute for a head-to-head randomized comparison, until the completion of ANNEXA-I we maintain this indirect comparison provides additional information to support clinicians in making treatment decisions.