The AZALEA-TIMI 71 Study and the Future of Factor XI Inhibition: Reflections from the American Heart Association Scientific Congress 2023

Abstract

Since its earliest days, the effective use of anticoagulation for prevention of stroke and other thromboembolic events has been limited by the risk and fear of bleeding, which was long believed to be inevitable. However, new understanding of the coagulation cascade suggests that, by targeting factor XI, it may be possible to protect patients from pathological thrombosis without significantly affecting physiological haemostasis, and thus greatly reduce the risk of bleeding. The AZALEA-TIMI 71 trial is the first study to provide definitive evidence that factor XI inhibition substantially reduces bleeding compared to a standard-of-care direct oral anticoagulant (DOAC). Based on an interview with Principal Investigator Christian T. Ruff, Thrombolysis in Myocardial Infarction (TIMI) Study Group, Boston, Massachusetts, USA, this article explains the significance of the AZALEA-TIMI 71 trial results, which showed an unprecedented reduction in the rate of bleeding with abelacimab, an investigational dual-acting factor XI/XIa inhibitor, compared with the DOAC rivaroxaban in patients with atrial fibrillation (AF) at moderate-to-high risk of stroke.