Anti-FXa activity and thrombin generation. Anti-FXa activity in cohorts 1 to 3 (A) and cohorts 4 to 6 (B). Thrombin generation in cohorts 1 to 3 (C) and cohorts 4 to 6 of the phase 2 study (D). All subjects had achieved steady-state concentrations of apixaban (5 mg twice a day) on day 6 prior to administration of andexanet. Values are means ± standard error of the mean. The pre-anticoagulant ranges on day 1 for thrombin generation are shown as mean ± 1 SD (light gray) and mean ± 2 SD (dark gray), respectively.