Johnson & Johnson stopped a mid‑stage trial of its anti‑tau antibody posdinemab after an interim review found the drug did not slow clinical decline versus placebo. The company said it will present full data later but has terminated the study. The failure dims prospects for this anti‑tau approach and may affect other programs targeting tau aggregation in Alzheimer’s disease. Tau-targeting antibodies are designed to neutralize toxic tau assemblies thought to drive neurodegeneration; this readout underlines the risk of translating target biology into clinical benefit.