Risk for Recurrent Venous Thromboembolism and Bleeding With Apixaban Compared With Rivaroxaban: An Analysis of Real-World Data

BACKGROUND: Apixaban and rivaroxaban are replacing vitamin K antagonists for the treatment of venous thromboembolism (VTE) in adults; however, head-to-head comparisons remain limited. OBJECTIVE: To assess the effectiveness and safety of apixaban compared with rivaroxaban in patients with VTE. DESIGN: Retrospective new-user cohort study. SETTING: U.S.-based commercial health care insurance database from 1 January 2015 to 30 June 2020. PARTICIPANTS: Adults with VTE who were newly prescribed apixaban or rivaroxaban. MEASUREMENTS: The primary effectiveness outcome was recurrent VTE, a composite of deep venous thrombosis and pulmonary embolism. The primary safety outcome was a composite of gastrointestinal and intracranial bleeding. RESULTS: Of 49 900 eligible patients with VTE, 18 618 were new users of apixaban and 18 618 were new users of rivaroxaban. Median follow-up was 102 days (25th, 75th percentiles: 30, 128 days) among apixaban and 105 days (25th, 75th percentiles: 30, 140 days) among rivaroxaban users. After propensity score matching, apixaban (vs. rivaroxaban) was associated with a lower rate for recurrent VTE (hazard ratio, 0.77 [95% CI, 0.69 to 0.87]) and bleeding (hazard ratio, 0.60 [CI, 0.53 to 0.69]). The absolute reduction in the probability of recurrent VTE with apixaban versus rivaroxaban was 0.006 (CI, 0.005 to 0.011) within 2 months and 0.011 (CI, 0.011 to 0.013) within 6 months of initiation. The absolute reduction in the probability of gastrointestinal and intracranial bleeding with apixaban versus rivaroxaban was 0.011 (CI, 0.010 to 0.011) within 2 months and 0.015 (CI, 0.013 to 0.015) within 6 months of initiation. LIMITATION: Short follow-up. CONCLUSION: In this population-based cohort study, patients with VTE who were new users of apixaban had lower rates for recurrent VTE and bleeding than new users of rivaroxaban. PRIMARY FUNDING SOURCE: None.