Clinical Summary
In this randomized international trial (COBRRA), investigators compared the bleeding risk of apixaban vs. rivaroxaban in patients with acute venous thromboembolism (VTE), including pulmonary embolism and proximal deep-vein thrombosis. A total of 2,760 patients were randomized to receive either apixaban (10 mg twice daily for 7 days followed by 5 mg twice daily) or rivaroxaban (15 mg twice daily for 21 days followed by 20 mg daily) for 3 months.
The primary endpoint—clinically relevant bleeding (major or clinically relevant nonmajor bleeding)—occurred significantly less often with apixaban (3.3%) compared with rivaroxaban (7.1%), corresponding to a 54% relative risk reduction (RR 0.46; 95% CI 0.33–0.65; P<0.001). Mortality rates were low and similar between groups.
Clinical implication: Apixaban demonstrated a substantially lower bleeding risk than rivaroxaban while maintaining similar clinical outcomes, suggesting it may be the safer first-line direct oral anticoagulant for treatment of acute VTE in routine clinical practice.