Apixaban bests rivaroxaban in new DOAC comparison
Apixaban is associated with a significantly lower risk of bleeding events than rivaroxaban in patients with acute venous thromboembolism (VTE), according to a new head-to-head comparison published in The New England Journal of Medicine.[1]
The COBRRA trial included more than 2,700 patients with acute symptomatic pulmonary embolism or proximal deep-vein thrombosis. Patients were randomized to receive of the two popular direct oral anticoagulants (DOACs)—apixaban or rivaroxaban—for three months. Apixaban doses were 10 mg twice daily for the first week and then 5 mg twice daily for the rest of the trial. Rivaroxaban doses were 15 mg twice daily for the first 21 days and then 20 mg daily for the rest of the trial.
All patients received care from December 2017 to January 2025. The mean age was 58.3 years old, and 43.5% of patients were women. A history of VTE was confirmed in 15.9% of patients.
“Clinical practice guidelines recommend direct oral anticoagulants as first-line therapy for acute venous thromboembolism because these agents have a better safety profile than vitamin K antagonists,” noted first author Lana A. Castellucci, MD, a researcher with the Ottawa Hospital Research Institute at the University of Ottawa, and colleagues. “Prospective direct comparison trials have been lacking, which has limited recommendations for the preference of apixaban or rivaroxaban.”
Castellucci et al. found that the study’s primary outcome, a composite of major bleeding or clinically relevant nonmajor bleeding, occurred in 3.3% of apixaban patients and 7.1% of rivaroxaban patients. Major bleeding events, meanwhile, occurred in 0.4% of apixaban patients and 2.4% of rivaroxaban patients. Recurrent VTE occurred in 1.1% of apixaban patients and 1% of rivaroxaban patients.
No bleeding-related deaths were reported in either group. Also, serious adverse events unrelated to bleeding or venous thrombosis occurred in 2.7% of apixaban patients and 2.2% of rivaroxaban patients. All-cause mortality occurred in 0.1% of apixaban patients and 0.3% of rivaroxaban patients.
The authors emphasized that it is unclear what, exactly, is responsible for this difference in bleeding risk. One potential explanation is the fact that the dosing schedules for the two drugs were different.
“In our trial, the difference in the risk of clinically relevant bleeding may be related to the dose of rivaroxaban, given that most of the difference seems to have occurred during the first three weeks of treatment, a period when rivaroxaban was given at a dose that was 50% higher than the maintenance dose,” the group wrote. “Despite this factor, the risk of recurrent VTE appeared to be similar in each treatment group. Further evaluation in clinical trials is needed to confirm whether the rivaroxaban dosing regimen contributed to the observed bleeding risks.”
Click here for the full study.
Michael has more than 19 years of experience as a professional writer and editor. He has written at length about cardiology, radiology, artificial intelligence and other key healthcare topics.