From the Guidelines
Andexa (andexanet alfa) is given to patients taking factor Xa inhibitors like rivaroxaban or apixaban when they experience life-threatening or uncontrolled bleeding, specifically indicated for patients who require urgent reversal of anticoagulation due to acute major bleeding episodes. The medication works as a recombinant modified human factor Xa protein that acts as a decoy, binding to factor Xa inhibitors in the bloodstream and neutralizing their anticoagulant effects, allowing the body's natural clotting mechanisms to function again, helping to stop the bleeding 1.
Key Considerations for Administration
- Andexa is administered as an intravenous bolus followed by a continuous infusion, with dosing based on the specific factor Xa inhibitor the patient is taking, the dose of that medication, and the time since the last dose 1.
- For patients taking rivaroxaban or apixaban, the dosing of andexanet alfa depends on the timing since last intake: a 400 mg bolus is administered followed by a 480 mg infusion (4 mg/min) if the last intake was > 7 h before reversal, and an 800 mg bolus followed by a 960 mg infusion (8 mg/min) is given if the last intake was < 7 h before reversal or unknown recent intake 1.
Monitoring and Restarting Anticoagulation
- After administration, patients require close monitoring for signs of thrombosis, and anticoagulation therapy may need to be restarted once the bleeding risk has resolved 1.
- The ANNEXA-4 study demonstrated the efficacy of andexanet alfa in reversing the anticoagulant effects of apixaban and rivaroxaban in patients with acute major bleeding, with good/excellent hemostasis achieved in 82% of patients at 12 hours 1.
Important Notes
- Andexa is not used prophylactically before procedures or for minor bleeding events, as it carries risks including thrombotic events 1.
- The medication's effects are transient, and anticoagulation therapy may need to be restarted once the bleeding risk has resolved 1.
From the Research
Andexa Administration
Andexa (andexanet alfa) is given to patients taking factor Xa inhibitors, such as rivaroxaban or apixaban, in the following situations:
- Life-threatening or uncontrolled bleeding 2, 3, 4, 5
- Urgent surgery, especially neurosurgical interventions 2
- Concomitant use of andexanet alfa and prothrombin complex concentrate 2
- Onset of bleeding more than 6 h prior to admission 2
Clinical Scenarios
Andexanet alfa may be beneficial in various clinical scenarios, including:
- Pre-treatment of urgent surgery 2
- Management of patients at high risk of thrombosis or recent arterial/venous thrombotic events 2
- Reversal of anticoagulation in patients with acute major bleeding on edoxaban 6
Administration and Efficacy
Andexanet alfa is administered as a bolus followed by a 120-minute continuous infusion 4