Andexanet alfa: administration quick reference guide (Guidelines)
TAM (Treatments and Medicines) NHS Highland
What's new / Latest updates
27/04/26 V1.1: Please note that table 1 formatting was incorrect, the less and more than 8 hours row had slipped 2 columns to the left. This has now been corrected.
It is used to reverse the effects of rivaroxaban or apixaban in life-threatening or uncontrolled bleeding.
Patients should receive either a LOW DOSE or HIGH DOSE regimen depending on the time/dose of their last oral anticoagulant. Both are given as an initial loading dose (15 to 30 minutes) followed by a 2 hour infusion. See full administration guide for further details.
Low dose regimen = 400 mg loading dose followed by 480 mg over 2 hours.
High dose regimen = 800 mg loading dose followed by 960 mg over 2 hours.
| Anticoagulant |
Last Dose |
Timing of last dose before andexanet alfa administration |
|
| Less than 8 hours or unknown | 8 or more hours | ||
| Rivaroxaban | ≤10 mg | LOW dose | LOW dose |
| >10 mg or unknown | HIGH dose | ||
| Apixaban | ≤5 mg | LOW dose | LOW dose |
| >5 mg or unknown | HIGH dose | ||
The volume, doses and rates required for each regimen is detailed below. Andexanet alfa comes as a 200 mg/20 mL vial (pack size of 4 vials). Dedicated syringe pumps with the loading and maintenance rates pre-programmed are available in each location andexanet is stocked, but as an additional safety measure these should be checked against the table below.
Low dose regimen |
High dose regimen |
|||
Loading dose |
Maintenance infusion |
Loading dose |
Maintenance infusion |
|
| Dose and millimetres required | 400 mg in 40 mL | 480 mg in 48 mL | 800 mg in 80 mL | 960 mg in 96 mL |
| Vials required | 2 | 3 (discard remainder of vial 3) | 4 | 5 (discard remainder of vial 5) |
| 50mL syringes required | One | One | Two = 40 mL per syringe | Two = 48 mL per syringe |
| Rate of administration via syringe pump | 160 mL/hr (bolus dose over 15 minutes) | 24 mL/hr (over 2 hours) | 160 mL/hour (over 30 minutes; each syringe will run for 15 minutes each) | 48 mL/hr (over 2 hours; each syringe will run for 60 minutes each) |
Once andexanet alfa has been administered please complete this form as soon as possible.