Background: Recent pivotal phase III trials involving direct oral anticoagulant (DOAC) versus low molecular weight heparin have demonstrated the utility of DOACs in Western patients with cancer-associated venous thromboembolism (VTE). However, these trials did not include Japanese patients. This phase II trial evaluated the safety and efficacy of apixaban in Japanese patients with cancer-associated VTE (UMIN000028447).
Method and results: Apixaban was initiated at 10 mg twice daily for 7 days, followed by 5 mg twice daily for 23 weeks. The primary endpoint was the incidence of major or clinically relevant non-major (CRNM) bleeding events during the treatment period. The study was terminated due to safety concerns after enrolling 27 patients. Median age was 71 years; median body weight was 51.3 kg; and major primary tumor sites were the gastrointestinal tract (26%) and lung (19%). During the median follow-up period of 5.4 months, major or CRNM bleeding occurred in in 26% of patients (major, n = 5; CRNM, n = 2; 95% confidence interval, 11-46%). No recurrent VTE or VTE-related death occurred. Estimated overall survival at 6 months was 68%.
Conclusion: This study demonstrated the excessive bleeding risk of apixaban at the standard dose in Japanese patients with cancer-associated VTE.
Keywords: Apixaban; Cancer-associated venous thromboembolism; Japanese; Phase II trial.
© 2022. Japanese Society of Hematology.