Test Code APIXA Apixaban, Anti-Xa, Plasma
Ordering Guidance
This assay is not indicated for monitoring low-molecular-weight heparin (LMWH) or unfractionated heparin (UFH) concentrations. The presence of UFH and LMWH will cause the apixaban anti-Xa level to be falsely elevated.
This assay is optimized to measure apixaban concentration in presence of coagulation factor Xa recombinant, inactivated-zhzo (andexanet alfa, Andexxa).
Necessary Information
Specimen Required
Specimen Type: Platelet-poor plasma
Collection Container/Tube: Light-blue top (3.2% sodium citrate)
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions:
1. Specimen should be collected 2 to 4 hours (peak) after a dose or just prior (trough) to the next dose for apixaban concentrations.
2. For complete instructions, see Coagulation Guidelines for Specimen Handling and Processing.
3. Centrifuge, transfer all plasma into a plastic vial, and centrifuge plasma again.
4. Aliquot plasma into a plastic vial leaving 0.25 mL in the bottom of centrifuged vial.
5. Freeze plasma immediately (no longer than 4 hours after collection) at -20° C or, ideally, ≤-40° C.
Additional Information:
1. A double-centrifuged specimen is critical for accurate results as platelet contamination may cause spurious results.
2. Each coagulation assay requested should have its own vial.
Forms
If not ordering electronically, complete, print, and send a Coagulation Test Request (T753) with the specimen.
Useful For
Measuring apixaban concentration in selected clinical situations (eg, renal insufficiency, assessment of compliance, periprocedural measurement of drug concentration, suspected overdose, advanced age, and extremes of body weight)
Special Instructions
Method Name
Chromogenic Assay
Reporting Name
Apixaban, Anti-Xa, PSpecimen Type
Plasma Na CitSpecimen Minimum Volume
0.5 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Plasma Na Cit | Frozen | 42 days |
Reference Values
An interpretive report will be provided.
Interpretation
The lower limit of detection of this assay is 10 ng/mL.
Therapeutic reference ranges have not been established. See Clinical Information for peak and trough drug concentrations observed from clinical trials.
Clinical Reference
1. Eliquis (apixaban). Package insert. Bristol-Meyers Squibb Company; Revised 11/2019
2. Hurst KV, O'Callaghan JM, Handa A. Quick reference guide to apixaban. Vasc Health Risk Manag. 2017;13:263-267
3. Granger CB, Alexander JH, McMurray JJ, et al. Apixaban versus warfarin in patient with atrial fibrillation. N Engl J Med. 2011;365(11):981-992
4. Frost C, Nepal S, Wang J, et al. Safety, pharmacokinetics and pharmacodynamics of multiple oral doses of apixaban, a factor Xa inhibitor, in healthy subjects. Br J Clin Pharmocol. 2013;76:(5):776-786
5. Agnelli G, Buller HR, Cohen A, et al. Oral apixaban for the treatment of acute venous thromboembolism. N Engl J Med. 2013;369(9):799-808
6. Siegal DM, Curnutte JT, Connolly SJ, et al. Andexanet alfa for reversal of factor Xa inhibitor activity. N Engl J Med. 2015;373(25):2413-2424
7. Martin K, Beyer-Westendorf J, Davidson BL, Huisman MV, Sandset PM, Moll S. Use of the direct oral anticoagulants in obese patients: guidance from the SSC of the ISTH. J Thromb Haemost. 2016;14(6):1308-1313
Day(s) Performed
Monday through Friday
Report Available
1 to 3 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test has been modified from the manufacturer's instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
80299LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
APIXA | Apixaban, Anti-Xa, P | 74214-8 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
APIX1 | Apixaban, Anti-Xa, P | 74214-8 |
APIX2 | Interpretation | 69049-5 |
APIX3 | Cautions | 62364-5 |