Abstract 14480: Safety and Efficacy of Direct Oral Anticoagulants vs Low Molecular Weight Heparin for Treatment of Venous Thromboembolism in Patients With Cancer

Introduction: Direct oral anticoagulants (DOACs) have been studied for treatment of venous thromboembolism (VTE) in patients with cancer. However, the trials have shown conflicting results when compared with low molecular weight heparin (LMWH). Therefore, we aimed to conduct an updated meta-analysis of the available studies.

Methods: Randomized controlled trials (RCTs) comparing DOAC vs LMWH for VTE treatment in cancer patients were searched from multiple online databases. The primary endpoints of interest were recurrent VTE, major bleeding, clinically relevant non major bleeding (CRNB) and mortality at the longest available follow up. A random-effects model was used to estimate risk ratios (RR) with 95% confidence intervals (CI).

Results: Six RCTs, with a total of 3,703 patients - 1,855 in the DOAC group and 1,848 in the LMWH group were included. Around 49% of patients were men and the mean age was 66 years. The follow up duration varied from 3 to 24 months. Patients treated with DOAC, when compared with the LMWH group, had lower risk of recurrent VTE (RR 0.66, 95% CI 0.52-0.83, p = 0.0005) (Figure 1), but a higher risk of CRNB (RR 1.63, 95% CI 1.19-2.23, p = 0.002). No significant differences were found between the two groups with regards to major bleeding (RR 1.19, 95% CI 0.82-1.71, p = 0.36) (Figure 2) or overall mortality (RR 1.02, 95% CI 0.90-1.14, p = 0.78).

Conclusions: For treatment of VTE, DOACs as compared with LMWH are associated with significant reduction of recurrent VTE events but with a higher risk of CRNB.