Comparative safety of direct oral anticoagulants and low-molecular-weight heparin in patients with venous thromboembolism and cancer in Europe.

Aim: This study aimed to compare the safety and effectiveness of direct oral anticoagulants (DOACs) with low-molecular-weight heparin (LMWH) in patients with venous thromboembolism (VTE) and active cancer in a real-world setting in Sweden, Norway, Finland, the UK and Germany. Materials & methods: This observational cohort study used datasets from Sweden, Norway, Finland (National Patient and Prescription Registers) the UK (Clinical Practice Research Datalink and Hospital Episode Statistics) and Germany (AOK Plus and GWQ) from 2013 to 2020. We identified treatment-naive adult patients with cancer-related VTE treated with a DOAC or LMWH. We employed inverse probability of treatment weighting for each DOAC-LMWH comparison and assessed recurrent VTE and bleeding risk (overall and by site: gastrointestinal [GI], intracranial hemorrhage [ICH] or other) within 6 months of treatment initiation. Fine-Gray models were fitted to estimate adjusted hazard ratios and country level estimates were meta-analyzed.

Results

After inverse probability of treatment weighting, 30,002 and 2892 patients were included in the LMWH-apixaban comparison, and 29,976 and 4321 in the LMWH-rivaroxaban comparison, respectively. Recurrent VTE could not be assessed comparatively because of low numbers. At 6 months, apixaban was associated with a lower risk of overall and other (HR: 0.67 [95% CI: 0.53,0.86]; 0.64 [0.41,0.998]) bleeding compared with LMWH, with similar risks for GI and ICH bleeding (0.89 [0.61,1.29]; 0.67 [0.31,1.44], respectively). Rivaroxaban had a similar risk of overall, GI, and other bleeding (0.98 [0.83, 1.15]; 0.86 [0.47,1.58]; 0.89 [0.74,1.08]) compared with LMWH, but a lower risk of ICH (0.32 [0.13, 0.82]).

Conclusion

These findings suggest that apixaban may offer a safer bleeding profile than LMWH for patients with cancer-associated VTE, particularly in reducing overall and other types of bleeding. Rivaroxaban also appears to be a viable alternative to LMWH, with a notably lower risk of ICH. These results provide valuable real-world insights in an area where evidence remains very limited and support the role of DOACs as a safe alternative to LMWH in patients with VTE and cancer.