Secondary Prophylaxis of Venous Thromboembolism (VTE) with Low Dose Apixaban or Rivaroxaban: Results from a Patient Population with More than 2 Years of Median Follow-up.

Background: Direct oral anticoagulants (DOACs) are widely used for the treatment and secondary prophylaxis of venous thromboembolism (VTE). Nowadays, DOACs represent the gold standard for long-term anticoagulation, with low-intensity DOACs administration becoming increasingly used worldwide in such scenario. Albeit low-intensity apixaban and rivaroxaban are approved for clinical usage as secondary VTE prophylaxis, there are few literature data regarding their efficacy and safety with a long follow-up.

Objectives: The aim of our study was to evaluate the efficacy and safety of low-dose DOACs for VTE secondary prophylaxis in patients at high risk of VTE recurrence.

Methods: We retrospectively evaluated patients who required long-term anticoagulant secondary prophylaxis to prevent recurrent VTE, treated with apixaban 2.5 mg BID or rivaroxaban 10 mg daily with a follow-up ≥ 12 months.

Results: The examined patients were 323. The median low-dose DOAC administration time was 25.40 months (IQR 13.93-45.90). Twelve (3.7%) VTE recurrences were observed; 21 bleeding events were registered (6.5%), including one episode of Major bleeding (MB) (0.3%), 8 Clinically relevant nonmajor bleeding (CRNMB) (2.5%) and 12 minor bleeding (3.7%). No statistically significant difference in the rate of VTE recurrence and/or bleeding events emerged between the rivaroxaban and apixaban groups. Patients included in the study for multiple episodes of VTE presented a significantly higher risk of a new VTE recurrence during low-intensity DOAC.

Conclusions: Our data suggest that low-dose DOACs may be effective and safe in secondary VTE prophylaxis in patients at high risk of VTE recurrence; however, attention might be needed in their choice in such a scenario for patients who experienced multiple episodes of VTE.