Loading Curie Briefs...
Getting the latest healthcare news for you
Getting the latest healthcare news for you
A major phase 3 trial of milvexian, a novel factor XIa inhibitor, was stopped early after the drug failed to reduce heart attacks, strokes, or cardiovascular death in patients recovering from acute coronary syndrome (ACS). On the bright side, it didn't increase serious bleeding either. Researchers say the safety data still bodes well for ongoing trials in atrial fibrillation and stroke prevention.
A promising anticoagulant comes up short in ACS patients
The LIBREXIA-ACS trial, a phase 3 randomized controlled trial, was halted early for futility after milvexian — an oral factor XIa inhibitor developed by Bristol Myers Squibb and Johnson & Johnson — failed to reduce major ischemic events in patients who recently experienced an acute coronary syndrome (ACS) event. The drug was added on top of standard antiplatelet therapy, but showed no meaningful benefit over placebo.
Factor XIa inhibitors had generated excitement because factor XI plays a key role in clot formation (thrombosis) but is less critical for normal bleeding control (hemostasis) — theoretically offering a safer anticoagulant option. While milvexian didn't deliver on the efficacy front in this setting, it also didn't increase serious bleeding, which researchers say is a meaningful silver lining.
By the Numbers
Why it matters: While milvexian won't be moving forward for ACS, its clean safety profile keeps hope alive for two other large ongoing trials — one in atrial fibrillation and one in secondary stroke prevention — where the drug may yet find its footing.
