Study Finds Most Patients with Atypical Alzheimer's Ineligible for New Anti-Amyloid Therapies

A study published in Neurology on August 5, 2026, reveals that 70% to 85% of patients with atypical Alzheimer's disease are ineligible for new anti-amyloid therapies like lecanemab and donanemab. Although these patients have the target amyloid pathology, standard cognitive screening tests like the Mini-Mental State Examination focus on memory and overestimate functional impairment in those with visual, language, or executive variants. Consequently, early-stage patients are unintentionally excluded from receiving these disease-modifying treatments.

Atypical Alzheimer's treatment eligibility

• ▪The Neurology study evaluated eligibility for the anti-amyloid therapies lecanemab and donanemab using clinical trial criteria and recommendations among 184 people with biomarker-confirmed atypical Alzheimer's disease.
• ▪A study published in Neurology on August 5, 2026, found that 70% to 85% of patients with atypical Alzheimer's disease would not meet eligibility requirements for newer anti-amyloid therapies.

Cognitive screening test limitations

• ▪The primary driver of treatment exclusion in the study was poor performance on cognitive screening tests, which accounted for 50% to 67% of the exclusions.
• ▪The Mini-Mental State Examination, an 11-question screening test weighted toward memory, was the most common cognitive test causing patient exclusions in the atypical Alzheimer's study.

Atypical Alzheimer's symptom variants

• ▪The study examined four atypical Alzheimer's variants: posterior cortical atrophy, logopenic variant primary progressive aphasia, dysexecutive Alzheimer's disease, and corticobasal syndrome.
• ▪Atypical Alzheimer's disease presents through symptoms affecting vision, language, executive function, or movement first, rather than memory loss.

Anti-amyloid therapy criteria mismatch

• ▪Study author Dror Shir stated that current cognitive screening tools might overestimate the functional stage of atypical Alzheimer's disease, creating a mismatch between eligibility criteria and patient symptoms.
• ▪The Neurology study was retrospective and based on existing clinical records, meaning researchers estimated treatment eligibility rather than evaluating patients directly.

Recent Alzheimer's treatment advances

• ▪The US Food and Drug Administration has approved the anti-amyloid antibodies lecanemab and donanemab for mild cognitive impairment due to Alzheimer's disease and mild Alzheimer's dementia.
• ▪The National Institute on Aging and Alzheimer's Association revised their diagnostic criteria for Alzheimer's disease in 2024.