Factor Xa Inhibition for the Treatment of Venous Thromboembolism Associated With Cancer: A Meta-Analysis of the Randomised Controlled Trials

Venous thromboembolism (VTE) is a common cause of morbidity and mortality in cancer patients. Until recently, guidelines recommended the use of low-molecular weight heparin (LMWH) as standard of care for VTE in patients with cancer. Despite the proven efficacy of direct oral anticoagulants (DOACs) for treatment of VTE, there is equipoise supporting their use in cancer patients. A systematic review of PubMed, Medline and EMBASE identified four randomised controlled trials (RCTs) in patients with cancer and VTE comparing a factor Xa inhibitor (FXaI) to LMWH. A meta-analysis was performed with a primary outcome of VTE recurrence and key secondary outcomes of major bleeding, clinically relevant non-major bleeding (CRNMB) and gastrointestinal (GI) bleeding. Four RCTs with 2,907 patients were included. 1,451 patients were randomised to FXaI and 1,456 to LMWH. VTE recurrence was lower in the FXaI group (RR 0.62, 95%CI 0.44–0.87; p=0.01; I2=24.90), with an absolute risk difference of -4% equating to a number needed to treat of 25 for prevention of recurrent VTE with FXaI. No significant difference in major bleeding was noted between groups (RR 1.33, 95%CI 0.84–2.11; p=0.23). Rates of GI bleeding (RR 1.87, 95%CI 1.06–3.29; p=0.03) and CRNMB (RR 1.57, 95%CI 1.11–2.23; p=0.01) were greater with FXaIs. In patients with cancer and VTE, the rate of VTE recurrence was significantly lower with FXaI than with LMWH without an increased risk of major bleeding. Our data supports the use of FXaIs as the standard of care for the treatment of VTE in this population.