Table 1.

Characteristics of Novel Oral Anticoagulants Compared With Warfarin11, 12, 13

	Warfarin	Dabigatran	Rivaroxaban	Apixaban
Target	Synthesis of vitamin K‐dependent clotting factors (factors II, VII, IX, and X)	Thrombin	Factor Xa	Factor Xa
Bioavailability	>95%	∼6%	>80%	>50%
Time to peak activity	72–96 hours	2 hours	2.5–4 hours	3 hours
Half‐life	40 hours	14–17 hours	5–9 hours (young healthy patients),11–13 hours (elderly patients)	8–15 hours
Dosing frequency in patients with AF	Once daily	Twice daily	Once daily	Twice daily
Interactions	Numerous drugs including substrates of CYP2C9, CYP3A4, and CYP1A2; various foods	Strong P‐gp inhibitors and inducers	Strong CYP3A4 inducers, strong inhibitors of both CYP3A4 and P‐gp	Strong inhibitors/inducers of both CYP3A4 and P‐gp
Renal elimination (absorbed active drug)	<1%	∼80%	∼33%a	∼27%

Abbreviations: AF, atrial fibrillation; CYP, cytochrome P450; P‐gp, P‐glycoprotein.

^aAn additional 33% of the absorbed rivaroxaban dose inactivated in the liver is also eliminated renally.