Building a biomarker stack to stratify Alzheimer’s trials

A run of recent studies is pushing neurodegeneration biomarkers past the binary question of whether pathology is present toward a layered set of plasma and CSF measures that can time disease before symptoms appear, gauge who will decline and how fast, and tell molecularly distinct pathologies apart.

Today's Alzheimer's trials already lean on a core biomarker toolkit — amyloid and tau PET, plus CSF and increasingly blood-based p-tau217 and β-amyloid 42, now with an FDA-cleared assay — to answer two largely yes-or-no questions: is Alzheimer's pathology present, and is this person likely to progress? Useful as that is, it stops well short of the finer-grained picture the newer markers promise...