Loading...
In patients who have completed courses of initial anticoagulation for unprovoked venous thromboembolism (VTE), extended treatment with warfarin, the oral factor Xa inhibitor rivaroxaban (Xarelto), or (to a lesser extent) aspirin can lower the rate of recurrence. How does apixaban (Eliquis), another oral factor Xa inhibitor, fare in this regard? In an industry-sponsored randomized trial, 2500 patients who had just completed 6 to 12 months of standard anticoagulation for deep venous thrombosis or pulmonary embolism received twice-daily doses of 5-mg apixaban, 2.5-mg apixaban, or placebo. The qualifying VTE events were unprovoked in 92% of cases.
During 1 year of treatment, the incidence of symptomatic or fatal recurrent VTE was 9% in the placebo group and 2% in both apixaban groups — a significant difference. For several composite endpoints that also included all-cause mortality or arterial thrombotic events, apixaban consistently conferred a 7- to 8-percentage-point advantage over placebo. Rates of major bleeding were lower than 1% in all three groups.
Agnelli G et al. Apixaban for extended treatment of venous thromboembolism. N Engl J Med 2012 Dec 8; [e-pub ahead of print]. (http://dx.doi.org/10.1056/NEJMoa1207541)
Comment
Apixaban recently was FDA-approved for patients with atrial fibrillation. If it is approved eventually for extended treatment following VTE, it will become another option for patients with this condition. However, several caveats apply: This study lasted for only 12 months, most participants were relatively young (mean age, 57), most had normal renal function, and the drug will be expensive. Studies in which apixaban and alternative therapies are compared directly, and additional data on safety and efficacy in older and sicker patients, would be valuable.