December 8th, 2012
Prolonged Anticoagulation with Apixaban Beneficial in Venous Thromboembolism
A new study suggests that extending anticoagulant therapy for an additional year may be beneficial after patients with venous thromboembolism complete their initial course of therapy. The results of AMPLIFY-EXT (Apixaban after the Initial Management of Pulmonary Embolism and Deep Vein Thrombosis with First-Line Therapy-Extended Treatment) were presented at the annual meeting of the American Society of Hematology meeting in Atlanta and published simultaneously in the New England Journal of Medicine.
After completing a standard anticoagulation regimen for 6 to 12 months, 2486 VTE patients were randomized to either placebo or apixaban (2.5 or 5 mg twice daily) for an additional 12 months. At both doses, apixaban treatment was associated with a large reduction in clinical events and no increase in major bleeding events.
The primary endpoint, the composite of death or symptomatic recurrent VTE, was significantly lower in the low-dose and high-dose apixaban groups (3.8% and 4.2%, respectively) than in the placebo group (11.6%).
Very few major bleeding events occurred: 4 (0.5%) in the placebo group, 2 (0.2%) in the low-dose apixaban group, and 1 (0.1%) in the high-dose apixaban group. Clinically relevant nonmajor bleeds occurred in 2.3% of the placebo group, 3.0% of the low-dose apixaban group, and 4.2% of the high-dose apixaban group.
The investigators concluded that the results of the study “provide a rationale for continuing anticoagulation therapy” in VTE patients for whom there is uncertainty about the worth of continued anticoagulant therapy. They calculated that 14 patients would need to be treated to prevent one VTE case.