Bristol Myers Squibb, in partnership with Johnson & Johnson, has scrapped a high-profile Phase 3 trial of its experimental anticoagulant milvexian after an independent review signaled the study was unlikely to hit its main target.
The Librexia ACS trial was testing whether adding milvexian to standard antiplatelet therapy could improve outcomes for patients recovering from a recent acute coronary syndrome event. A preplanned interim analysis by the Independent Data Monitoring Committee found the drug was not on track to meet its primary efficacy goal — prompting the companies to pull the plug.
Importantly, no new safety issues emerged. Investigators said milvexian’s safety profile aligned with earlier data, as per a release.
The setback affects only one arm of the sweeping Librexia development program. Two other late-stage trials — Librexia AF for atrial fibrillation and Librexia STROKE for secondary stroke prevention — will continue as planned. Topline results from those studies are expected in 2026.
“Together with Johnson & Johnson, we remain confident in the potential of milvexian to redefine anticoagulant therapy,” said Roland Chen, senior vice president for drug development at Bristol Myers Squibb. He emphasized that the AF and stroke-prevention studies differ markedly from the ACS trial in their patient populations, treatment backgrounds and endpoints.
Program chair Robert A. Harrington, of Weill Cornell Medicine, said the news underscores “the complexity of treating ACS,” but added that factor XIa inhibition — milvexian’s mechanism — remains a promising avenue for advancing clot-prevention therapies.
Investigators will be briefed, and the companies plan to present the ACS data at a future medical meeting.
Acute coronary syndrome — which includes heart attacks and unstable angina — affects more than seven million people worldwide each year.
