Real world utilization of Andexanet alfa in the management of oral factor Xa inhibitor-associated gastrointestinal bleeding

Background: Andexanet alfa (AA) is approved for reversal of factor Xa inhibitor (FXaI) bleeds; however, there are limited reports of its use for gastrointestinal bleeding (GIB) in real-world populations. The objective of this study was to report real-world utilization and evaluation of the effectiveness of AA for FXaI-associated GIB. Methods: This retrospective cohort study including consecutive patients receiving AA for FXaI-associated GIB (7/2018–2/2021). Demographics, blood product administration, hemostatic efficacy, rebleeding, thrombosis, and mortality rates were collected. Hemostatic efficacy (HE), based on corrected hemoglobin at 12 h compared to baseline, was categorized as excellent (<10% decrease), good (≤ 20% decrease), or poor (>20% decrease, > 2 units of additional coagulation intervention or death prior to repeat hemoglobin). Comparative transfusion requirements between efficacy groups was assessed by Wilcoxon-Rank test. Results: Twenty-two patients were included (64% male, median (IQR) age 76 years (67, 80). Most patients (59%, n = 13) were on apixaban, and the primary anticoagulation indication was atrial fibrillation (64%, n = 14). Median initial hemoglobin was 7.5 g/dL (IQR 6.4, 8.8) and 50% (n = 11) were upper GIB. Hemostatic efficacy was excellent in 46% (n = 10), good in 23% (n = 5), and poor in 32% (n = 7). There was no statistically significant difference in red blood cells (RBCs) received between those with excellent/good hemostasis (median 2, IQR 1 to 2) and those with poor hemostasis (median 4, IQR 1.5 to 4.5). Two patients (9%) had arterial thrombotic events within 30 days of reversal. Conclusion: In this multicenter, single arm, real-world observational analysis of patients with factor Xa inhibitor associated GIB most patients achieved good hemostasis following administration of AA. There was a 9% 30-day thrombotic event rate. The lack of a control group limits the strength of the conclusions that can be drawn from this study.