To measure plasma apixaban concentration in ng/mL.
Freeze/thaw cycles: stable x6
Ambient - 6 hours
Chromogenic anti-Xa. Apixaban inhibition of factor Xa (present in excess). Residual Xa is measured using a chromogen and is inversely proportional to the apixaban present.
Although routine monitoring is not needed, there are a number of clinical circumstances in which clinicians want or need to know a patient's Apixaban level. Levels can be accurately and precisely measured using either a chromogenic anti-Xa assay or LC/MS-MS.