Andexanet alfa for the reversal of anticoagulation: Dutch practice data

Andexanet alfa is a reversal agent for factor Xa (FXa) inhibitors (rivaroxaban and apixaban) and is available for the treatment of severe FXa inhibitor-associated bleeding. However, an increase in thrombotic events after administration has been reported.

This multicenter Dutch observational study aimed to provide insights into the characteristics, usage patterns, and clinical outcomes of the Dutch patient population treated with andexanet alfa.

We included all patients treated with on- and off-label andexanet alfa from 6 of the 11 hospitals in the Netherlands that prescribed andexanet alfa between June 2019 and December 2023. Data were collected by LOGEX, a Dutch healthcare data company, using healthcare administrative data and questionnaires completed by clinicians at participating centers. Patient characteristics, details related to andexanet alfa administration, and 30-day clinical outcomes, including thrombotic events and all-cause mortality, were collected.

A total of 217 patients received andexanet alfa, including 192 treated on-label and 25 off-label. In the on-label group, the median age was 77 years (IQR, 69-82 years), and intracranial hemorrhage was the most common indication for reversal (61%). Most patients received a low dose (≤1000 mg) and were administered andexanet alfa within 4 hours of hospital admission (79%). The overall 30-day cumulative incidence of thrombotic events was 4.6%, and no thrombotic events occurred after anticoagulation was reinitiated. All-cause mortality was 34%, with similar rates between the on- and off-label groups.

Andexanet alfa was primarily prescribed for the reversal of FXa inhibitors in patients with intracerebral hemorrhage. We observed a lower incidence of thrombotic events than reported in clinical trials.