Evaluation of anticoagulation re-initiation practices following reversal of factor Xa inhibitors with andexanet alfa or 4F-PCC in patients with major bleeding events

Both andexanet alfa and 4F-PCC reversal strategies have been associated with thrombotic events. It remains unclear whether the risk is associated with the reversal agent or the lack of re-initiation of anticoagulation. The aim of this study was to describe anticoagulant (AC) re-initiation patterns in patients presenting with major bleeding while on a FXai requiring reversal, and to describe associated post-reversal thrombotic events. This was a single-center retrospective cohort study. Patients were included if they received FXai reversal with andexanet alfa or 4F-PCC for major bleeding. Fifty-seven patients met inclusion criteria; of these patients, 34 received andexanet alfa and 23 patients received 4F-PCC. Most patients were prescribed AC for atrial fibrillation. The most common indications for reversal were intracranial hemorrhage 68%, followed by gastrointestinal bleeding 19%. AC was re-initiated at either prophylactic or therapeutic doses in 59% in the andexanet alfa recipients and 65% in the 4F-PCC recipients within 30 days. In those who restarted AC within 30 days, the median time to re-initiate AC was three days [IQR: 1–3]. Thrombotic events occurred in 3% of patients in the andexanet alfa group and 13% in the 4F-PCC group (7% overall rate). None were receiving anticoagulation at the time of the event. Anticoagulation was restarted in approximately half of the patients who received a reversal agent for a life-threatening bleed. The thrombotic risk was 7% at the 30 day follow up period. Continuous assessment of bleeding and thrombosis is important for post-reversal management of patients with major bleeding events.