Table 1.

Apixaban pharmacokinetics and pharmacodynamics13,15–17

Mechanism of action	Factor Xa inhibitor
Bioavailability	50%, gastrointestinal
T (max)	3–4 hours
Distribution	87% protein bound
Half-life	8–13 hours (prolonged in renal impairment)
Monitoring	None required. Anti-Xa assay useful in determining if anticoagulant effect present
Dosing	Nonvalvular atrial fibrillation: 5 mg twice daily
	THR prophylaxis: 2.5 mg twice daily for 35 days
	TKR prophylaxis: 2.5 mg twice daily for 12 days
	VTE treatment: 10 mg twice daily for 7 days, then 5 mg twice daily
	Prophylaxis of recurrent VTE: 2.5 mg twice daily after at least 6 months of treatment
Dose adjustments	In patients with nonvalvular atrial fibrillation and at least two of the following: Age ≥80 years, body weight ≤60 kg, or serum creatinine ≥1.5 mg/dL, recommended dose is 2.5 mg twice daily
Metabolism	Hepatic CYP3A4 system
Elimination	25% renal, 75% biliary
Drug interactions	Potent P-gp and CYP3A4 inhibitors or inducers

Abbreviations: THR, total hip replacement; TKR, total knee replacement; VTE, venous thromboembolism; P-glycoprotein.