Apixaban may be associated with better prevention of recurrent venous thromboembolism (VTE) and major bleeding, according to research published in The Lancet Haematology.
Direct-acting oral anticoagulants (DOACs), including apixaban and rivaroxaban, have emerged in recent years as favorable therapeutic options for patients with VTE. However, no prior studies have compared the safety and efficacy of different DOACs.
In this study, researchers conducted a retrospective cohort analysis using data from the Truven Health MarketScan commercial and Medicare Supplement claims databases. In total, 15,254 treatment-naive, newly diagnosed patients with VTE who were recently initiated on apixaban (3091 patients) or rivaroxaban (12,163 patients) were evaluated.
Primary outcomes included incidence of recurrent VTE and major bleeding events. The secondary outcome was incidence of minor bleeding. Propensity score matching was used to adjust for potential confounding factors.
Among patients receiving apixaban, the incidence of both recurrent VTE and major bleeding was 3 per 100 person-years. Among patients receiving rivaroxaban, the incidence of recurrent VTE was 7 per 100 person-years, and the incidence of major bleeding was 6 per 100 person-years. The incidence of minor bleeding was 20 per 100 person-years and 34 per 100 person-years in the apixaban and rivaroxaban groups, respectively.
In the Cox proportional hazards model, apixaban was associated with decreased risk of VTE recurrence (hazard ratio [HR] 0.37; P <.0001), major bleeding (HR 0.54; P =.0031), and minor bleeding (HR 0.57; P <.0001).
Additionally, results from a subgroup analysis suggested that patients older than 65 years may have different outcomes compared with younger patients. However, the authors were unable to explain this interaction and noted that future studies are warranted to assess the potential benefit of apixaban in patients aged 65 years or older.
The authors acknowledged some limitations to their study, including their inability to capture fatal outcome events that occurred in inpatients settings and their decision to exclude other therapeutic drugs, such as warfarin and dabigatran, from their comparison. They cautioned that generalizability of their results to populations other than patients with VTE who have been covered by commercial or Medicare Supplement insurance for at least 1 year may be restricted.
1. Dawwas GK, Brown J, Dietrich E, Park H. Effectiveness and safety of apixaban versus rivaroxaban for prevention of recurrent venous thromboembolism and adverse bleeding events in patients with venous thromboembolism: a retrospective population-based cohort analysis [published online December 14, 2018]. Lancet Haematol. doi: 10.1016/S2352-3026(18)30191-1