Abstract
Apixaban is an oral, direct, competitive and highly selective factor Xa inhibitor that joins rivaroxaban in the newly constituted family of xabans. Oral administration is a benefit, particularly in patients who need longer anticoagulation therapy.
A direct factor Xa inhibition has the advantages of being effective independently of the presence of antithrombin and of involving even factor Xa bound to fibrin. Thus the anticoagulant effect is more reliable and, once subsided, it is devoid of rebound risk.
The pharmacokinetic properties are characterized by more than 50% bioavailability, a long plasma half-life of over 12 hours, double (hepatic and renal) excretion, uncomplicated metabolism with a low risk of drug-drug interactions, and a very low interindividual and intraindividual variability in the effect. The clinical effect of apixaban was tested particularly in thromboembolic disease (TED) prophylaxis in patients after weight-bearing joint (hip and knee) replacement.
Results of several studies within the Atherosclerotic Disease, VAscular functioN, and genetiC Epidemiology (ADVANCE) study proved apixaban at a dose of 2.5 mg twice daily to be comparably effective as and, at the same time, safer than enoxaparin at a dose of 30 mg twice daily or to have a superior prophylactic effect and comparable bleeding risk to enoxaparin at a dose of 40 mg once daily. Based on these data, apixaban has been approved for use in the above-mentioned indication.
Apixaban has also been reported to be effective in the prophylaxis of thromboembolic events in patients with atrial fibrillation, but has not yet been authorized for clinical use in this indication.