Table 3.

Effect of apixaban on coagulation assays26,27

Measurement	Effect
PT	Prolonged, dose-dependent
PTT	Prolonged, dose-dependent
INR	Increased, dose-dependent
PTT-based lupus anticoagulant	Prolonged, dose-dependent
dRVVT	Prolonged, dose-dependent
Thrombin time	No effect
Protein C activity	No effect
Free protein S antigen	No effect
Fibrinogen	No effect
Antithrombin	Potential effect depending upon specific assay
Factor Xa assay	Linear correlation, high sensitivity

Abbreviations: PT, prothrombin time; PTT, partial thromboplastin time; INR, international normalized ratio; dRVVT, dilute Russell’s viper venom time.