Facing the challenge of venous thromboembolism prevention in patients undergoing major abdominal surgical procedures for gastrointestinal cancer

Table 3 Comparative evaluation of mechanism of action and contra-indications of novel oral anticoagulants

Novel oral anticoagulants	Dabigatran	Rivaroxaban	Apixaban	Edoxaban
Mechanism of action	Direct thrombin (factor IIa) inhibitor	Direct factor Xa inhibitor	Direct factor Xa inhibitor	Direct factor Xa inhibitor
Route of administration	Per os	Per os	Per os	Per os
Half-life	12-14 h	7-11 h	12 h	8-10 h
Bioavailability	3%-7%	80%-100%	50%	62%
Metabolism	P-glycoprotein	P-glycoprotein Cytochrome P450 system (CYP3A4)	P-glycoprotein Cytochrome P450 system (CYP3A4)	P-glycoprotein Cytochrome P450 system (CYP3A4)
Excretion	Urine (80%)	Urine and HBR	Urine (25%)	Primarily: HBR Secondarily: Urine
Contraindication	CrCl < 30 mL/min	CrCl < 30 mL/min Hemodialysis Child Pugh B and C stage cirrhosis	CrCl < 15 mL/min
FDA approval	VTE prophylaxis after hip and knee arthroplasty, Non valvular atrial fibrillation VTE treatment	VTE prophylaxis after hip and knee arthroplasty, Non valvular atrial fibrillation VTE treatment	Non valvular atrial fibrillation VTE treatment and prevention after major orthopedic surgery	Non valvular atrial fibrillation VTE treatment and prevention after major orthopedic surgery
Clinical trials	Non-inferiority to warfarin Superiority to placebo	Non-inferiority to VKA/LMWH Superiority to placebo	-
Dosage	100-150 mg × 2/24 h	10-30 mg × 1/24 h	2.5-5 mg × 2/24 h	15-30 mg × 1/24 h

HBR: Hepatobiliary route; VTE: Venous thromboembolism; VKA: Vitamin K antagonists; LMWH: Low molecular weight heparin.