Abnormal tau aggregation is a hallmark of Alzheimer’s disease (AD) and a major contributor to neurodegeneration, synaptic dysfunction, and progressive functional decline. Antibodies against extracellular tau represent a potential therapeutic approach aimed at reducing pathological spread and delaying the clinical progression of AD. Researchers from Merck & Co., Inc. presented the preclinical development of MK-2214, a murine IgG2a monoclonal antibody that selectively targets the pathological phospho-epitope pSer413 of the tau protein.