Anti-fXa activity was measured to assess the ability of andexanet to reverse the anticoagulant effect of FXa inhibitors. Baseline was defined as the last value obtained prior to the start of the andexanet bolus. The change from baseline was calculated as the reduction in anti-fXa activity from baseline to the on-treatment nadir (that is, the minimum value between end of bolus and end of infusion). Percent reduction was calculated as the ratio between the maximum change from baseline and the baseline value, multiplied by 100.

Hemostatic efficacy was achieved when the body had time to produce thrombin and a subsequent clot and was rated by the EAC as: excellent; good; poor/none; not evaluable due to non-administrative reasons; not evaluable due to administrative reasons. These ratings were based on pre-specified criteria that were included in the EAC Charter. The EAC was blinded to anti-fXa activity levels. Participant results were classified as either success or failure based on the hemostatic efficacy rating (success = excellent/good, failure = poor/none). Participants rated by the EAC as non-evaluable due to administrative reasons were excluded from the analysis of hemostatic efficacy.