Efficacy and safety of direct oral anticoagulants for risk of cancer-associated venous thromboembolism

Efficacy and safety of direct oral anticoagulants (DOACs) for preventing primary and recurrent venous thromboembolism (VTE) in patients with cancer remain unclear. In this study, we conducted a systematic review to summarize the most up-to-date evidence from randomized controlled trials (RCTs). Our primary outcomes included the benefit outcome (VTE) and safety outcome (major bleeding). A random-effects model was used to pool the relative risks (RRs) for data syntheses. The Grading of Recommendations Assessment, Development and Evaluation tool was used to evaluate the quality of the entire body of evidence across studies. We included 11 RCTs with a total of 3741 patients with cancer for analyses. The DOACs were significantly related with a reduced risk of VTE when compared with non-DOACs: RR = 0.77, 95% confidence interval [CI]: 0.61-0.99, P = .04. Nonsignificant trend towards a higher risk of major bleeding was found in DOACs: RR = 1.28 95% CI: 0.81-2.02, P = .29. The quality of the entire body of evidence was graded as moderate for risk of VTE, and low for risk of major bleeding. To summarize, DOACs were found to have a favorable effect on risk of VTE but a nonsignificant higher risk of major bleeding compared with non-DOACs in patients with cancer. The safety effect of DOACs in patients with cancer requires further evaluation in adequately powered and designed studies.