Coagulation Factor Xa (Recombinant), Inactivated-Zhzo (Andexanet Alfa) Hemostatic Outcomes and Thrombotic Event Incidence at an Academic Medical Center

Andexanet alfa is approved for the reversal of factor Xa inhibitors in patients with major bleeding events. We aimed to review the incidence of effective hemostasis with andexanet alfa in a real-world environment. This retrospective cohort included patients hospitalized for a major bleed that resulted in andexanet alfa administration. The primary outcome was effective hemostasis at 12 hours after andexanet alfa treatment. Thromboembolic events and mortality within 30 days were also assessed. Over a 14-month period, 13 patients received andexanet alfa with a mean age of 69 ± 10 years, 54% male, 69% exposed to apixaban (31% rivaroxaban), and had intracranial (46%) and nonintracranial (54%) bleeding sites. Effective hemostasis was observed in 10 (77%) patients. Four (31%) patients experienced 5 thromboembolic events with a median time to event of 6.5 days (range: 0.5-29). Four thrombotic events occurred during the period in which anticoagulation (prophylaxis or therapeutic) was not restarted. Mortality rate was 15%. Andexanet alfa was effective in obtaining hemostasis in a majority of patients. However, the incidence of thromboembolic events was high and may be attributed to a delay in restarting anticoagulation.