This article reports on two randomized, double-blind, placebo-controlled Phase 3 trials evaluating bapineuzumab, a humanized monoclonal antibody targeting β-amyloid, in patients with mild-to-moderate Alzheimer's disease (AD). One trial enrolled APOE ε4 carriers, and the other enrolled noncarriers. Despite some biomarker changes—such as reduced cerebrospinal fluid phosphorylated tau levels and stabilization
