Management of Venous Thromboembolism in Patients with Advanced Gastrointestinal Cancers: What Is the Role of Novel Oral Anticoagulants?

Table 2

Characteristics of currently available anticoagulants.

	Unfractionated heparin	Low molecular weight heparin	Fondaparinux	VKA
	Target antithrombin	Factor Xa, IIa (variable)	Xa	Factors II, VII, IX, X
Advantages	(1) Rapid onset of action	(1) Rapid onset of action	(1) Rapid onset of action	(1) Orally administered
	(2) Reversible	(2) Partially reversible	(2) No monitoring required	(2) Reversible
	(3) Can be used in renal dysfunction	(3) No drug-drug interactions	(3) Fixed dose	(3) Can be used in renal dysfunction
	(4) No drug-drug interactions	(4) No monitoring required
		(5) Fixed dose
	(1) Requires monitoring (platelet, PTT)	(1) Heparin-induced thrombocytopenia*	(1) Frequent injections	(1) Requires monitoring (INR)
	(2) Frequent injections	(2) Cannot be used in severe renal dysfunction	(2) No antidote	(2) Drug-drug interactions
	(3) Heparin-induced thrombocytopenia	(3) Frequent injections	(3) Cannot be used in severe renal dysfunction	(3) Food interactions
Disadvantages	(4) Requires dose adjustment	(4) Bleeding risk	(4) Bleeding risk	(4) Narrow therapeutic window
	(5) Bleeding risk			(5) Delayed onset of action/cannot be used alone in acute VTE
	(6) Risk of osteoporosis			(6) Requires dose adjustment
				(7) Bleeding risk

*Lower risk than unfractionated heparin.