Factor XI/XIA inhibitors: a new class of anticoagulant drugs
General Medicine, 2026, 28(1), 56-68.
R. Nikolov1, G. Bogdanov1, S. Yovinska1, A. Pavlov2, K. Raychev2, V. Pencheva3
1Department of Pharmacology and Toxicology, Faculty of Medicine, Medical University – Sofia
2Faculty of Medicine, Medical University – Sofia
3Department of Propedeutics of Internal Medicine, Faculty of Medicine, Medical University – Sofia
Abstract. Anticoagulant therapy is essential in the treatment and prevention of the venous and arterial thromboembolic events. Due to their more favorable risk-benefit profile, oral direct factor Xa inhibitors (rivaroxaban, apixaban, edoxaban, betrixaban) and oral direct thrombin inhibitors (ximelagatran, dabigatran etexilate) have replaced vitamin K antagonists (acenocoumarol, warfarin) in a large proportion of patients with indications for oral anticoagulant therapy over the past ten years. Based on the role of factor XIa in thrombosis and its limited contribution to hemostasis, factor XI/XIa represents an important target for the introduction of new anticoagulants. Factor XI inhibitors are a new class of anticoagulants that selectively reduce the risk of thrombosis without significantly affecting the physiological mechanisms of hemostasis. Their pharmacological action is achieved by reducing the synthesis or inhibiting the activity of factor XI, a crucial factor in the coagulation cascade. The review presents data from clinical trials with abelacimab, milvexian, and asundexian.
Key words: factor XI, abelacimab, milvexian, asundexian
Address for correspondence: Rumen Nikolov, e-mail: rnikolov@medfac.mu-sofia.bg