Proceedings of the 13th International Conference on Thrombosis and Hemostasis Issues in Cancer, 2026
Vol. 5 No. s1 (2026)
Factor XI inhibitors in cancer-associated venous thromboembolism: what’s next?
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All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.
Published: 16 April 2026
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Venous thromboembolism (VTE) is an important cause of morbidity and mortality in individuals with active cancer. Most cancer-associated VTE occurs in the ambulatory setting in individuals receiving systemic therapy. Multiple anticoagulants are currently available for the treatment of cancer-associated VTE; a major drawback is the risk of bleeding. No drugs are currently approved for primary prevention of VTE in cancer in the outpatient setting. Adherence/compliance issues, drug-drug interactions, and concern about renal and hepatic metabolism are other ongoing concerns with these agents. Thus, there are major unmet needs in the quest to optimize the treatment and prevention of VTE in cancer. Factor XI (FXI) has only a small impact on hemostasis but contributes significantly to thrombosis. It is therefore a potential therapeutic target with less concern for enhancing bleeding. Several early-phase studies suggest that FXI inhibitors have reduced the risk of bleeding at therapeutic doses in the prevention of venous and arterial events in cardiology and postoperative settings. Multiple studies are now addressing the utility of this new class of drugs in cancer-associated VTE, including completed, ongoing, and planned trials of primary prevention and treatment. This narrative review addresses the role of FXI in thrombosis, the rationale for FXI inhibitors in primary and secondary prevention settings in malignancy and provides an overview of preliminary results and future directions.
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Dave HM, Patel MH, McCrae KR, Khorana AA. Factor XI inhibitors in cancer-associated venous thromboembolism: what’s next?. Bleeding Thromb Vasc Biol [Internet]. 2026 Apr. 16 [cited 2026 Apr. 17];5(s1). Available from: https://www.btvb.org/btvb/article/view/424
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