The New England Journal of MedicineAndexanet for Factor Xa Inhibitor–Associated Acute Intracerebral Hemorrhage

Andexanet alfa shows efficacy in controlling hematoma expansion in intracerebral hemorrhage patients on factor Xa inhibitors but poses an increased risk of thrombotic events.

A recent study published in the New England Journal of Medicine evaluates the use of andexanet alfa in patients with acute intracerebral hemorrhage who are receiving factor Xa inhibitors. The trial compared andexanet alfa with usual care, focusing on hemostatic efficacy and safety outcomes, providing significant insights for managing this patient population.

Study Design:

• Participants: 530 patients who had taken factor Xa inhibitors within 15 hours before having an acute intracerebral hemorrhage.
• Randomization: Patients were randomly assigned in a 1:1 ratio to receive andexanet alfa or usual care.
• Primary End Point: Hemostatic efficacy, defined by hematoma volume expansion of 35% or less at 12 hours, an increase in NIH Stroke Scale score of less than 7 points at 12 hours, and no receipt of rescue therapy between 3 and 12 hours.
• Safety End Points: Thrombotic events and death.

Key Findings:

• Hemostatic Efficacy: Achieved in 67.0% of patients receiving andexanet compared to 53.1% receiving usual care (adjusted difference, 13.4 percentage points; 95% CI, 4.6 to 22.2; P=0.003).
• Reduction in Anti-Factor Xa Activity: Median reduction from baseline to the 1-to-2-hour nadir was 94.5% with andexanet and 26.9% with usual care (P<0.001).
• Thrombotic Events: Occurred in 10.3% of patients receiving andexanet and 5.6% receiving usual care (difference, 4.6 percentage points; 95% CI, 0.1 to 9.2; P=0.048). Ischemic stroke occurred in 6.5% and 1.5% of patients, respectively.
• Mortality and Functional Outcome: No appreciable differences in the modified Rankin scale score or in death within 30 days between the groups.

HCN Medical Memo
Physicians should weigh the benefits of improved hemostatic efficacy with andexanet alfa against its higher risk of thrombotic events when treating patients with intracerebral hemorrhage who are on factor Xa inhibitors. Close monitoring for thrombotic complications is recommended in this patient population.

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