Alzheimer's Access, Biomarkers, Prevention, and Biological Heterogeneity

Only about 15,000 of 1 million eligible Americans have received anti-amyloid therapy. A retrospective study found that only roughly 15%–17% of patients with atypical, biomarker-confirmed Alzheimer disease met pivotal-trial eligibility, mainly because of MMSE, age, and MRI thresholds, reinforcing concerns about real-world generalizability. p-tau217 and related blood biomarkers may support diagnosis and treatment triage, but assay standardization, MRI monitoring, ARIA, cost, durability, mixed pathology, and clinical follow-through remain unresolved.