Introduction: The special needs of cancer patients offer unique challenges in treating them for venous thromboembolism (VTE). Dabigatran is a novel oral anticoagulant (NOAC) that may be comparable to warfarin in clinical benefit and risks of bleeding. A meta-analysis and systematic review was performed to compare efficacy of prevention of VTE recurrence and risks of bleeding with dabigatran compared to warfarin.

Methods: Randomized-controlled trials (RCTs) from various sources comparing dabigatran with warfarin for the prevention of recurrence of VTE were then retrieved and analyzed. The efficacy outcomes looked into was recurrence of VTE and mortality related to VTE while the primary safety outcome looked into was major bleeding.

Results: This meta-analysis, which included the studies, RECOVER I, RECOVER II, REMEDY showed that VTE and VTE-related deaths occurred in six out of 174 (3.4%) of cancer patients treated with dabigatran while four out of 166 (3.6%) cancer patients treated with warfarin with a relative risk of 1.44 with a 95% CI of 0.41, 5.03 showing no significant difference between dabigatran and warfarin.

The REMEDY trial included a total of 60 cancer patients from a total of 1,430 patients in the dabigatran group versus 59 cancer patients from a total of 1,426 patients in the warfarin group. Under the outcome of major bleeding event, among all patients who received dabigatran, 13 patients had major bleeding events, while among those who received warfarin, 25 patients had major bleeding events with a hazard ratio of 0.52 and 95% CI of 0.27-1.02. With the RECOVER I, and RECOVER II, among cancer patients analysed, four patients of the 105 who received dabigatran had major bleeding; while three of the 100 patients who received warfarin had major bleeding with a HR of 1.23 (95% CI of 0.28-5.5).

Conclusion: The authors conclude that dabigatran is comparable to warfarin in the prevention of recurrence of VTE among cancer patients in terms of both benefits and risks.

Keywords: venous thromboembolism, novel oral anticoagulant, cancer

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