The half-life of Andexxa is far shorter than the FXa inhibitors. Because of the short duration of action, anti-FXa activity starts to resume to baseline after the 2-hour infusion and goes back to the ...baseline by 4 hours after drug initiation. According to the ANNEXA-4 study, “there was no significant relationship between the hemostatic efficacy and a reduction in anti-factor Xa activity during andexanet treatment” despite the attractiveness of the concept 2. Based on the ICH score system, ICH volume ≥ 30 cc receives one point which correlates with increased mortality rates. ...the patients in the ANNEXA-4 study would expect to have a lower ICH score and should do better when compared to any group without this exclusion. Given the very sharp change in expected mortality rates between ICH scores of 0, 1, 2, and 3, data for ICH score would shed light on the reported mortality despite the fact that the ICH score has been validated in ICH secondary to vitamin K antagonist and not specifically for NOACs 16.
Cognitive Bias and Optimal Medical Decision Making We thank Dr. Mahan for his detailed and thoughtful response to our discussion on adding Andexxa (andexanet alfa) to formulary. ...the data applies ...to all types of bleeding and does not provide information on the use of PCC in those with life-threatening bleeding. ...the last line of the abstract states “unaccounted bias and confounding factors may occur in this type of comparison.” ...that time, stakeholders should ensure that cognitive bias to authority such as a guideline does not interfere with careful analysis of the underlying assumptions, weighing the type of evidence, and separating out facts from unwarranted extrapolations.
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