Bayer disclosed Phase 3 data showing its factor XIa inhibitor asundexian cut recurrent ischemic strokes by 26% without new safety signals, a finding presented at the International Stroke Conference. The result positions asundexian as a potential new option for secondary stroke prevention and raises commercial stakes for rival factor XIa programs. The data were unexpected and may reshape competitive dynamics: Bristol Myers Squibb and Johnson & Johnson are advancing rival XIa inhibitors and now face heightened efficacy benchmarks. Bayer’s readout included detailed subgroup and safety information that regulatory reviewers and investors will scrutinize. Clinicians and guideline panels will await full datasets, but the topline reduction—if replicated and robust across endpoints—could unlock a major indication for an emerging anticoagulant class that aims to lower thrombotic risk while minimizing bleeding.