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FDA clears first blood test to rule out Alzheimer’s in primary care

October 16, 2025

FDA cleared Roche’s Elecsys pTau18, the first blood-based biomarker test authorized for use in primary care to help rule out Alzheimer’s-related amyloid pathology. Designed for adults >55 years with cognitive symptoms, the test offers a minimally invasive alternative to PET imaging or CSF analysis, enabling earlier triage and more efficient diagnostic pathways.

Clinical performance was evaluated in a multicenter, non-interventional study of 312 participants, representative of a low-prevalence, early-stage population typical of primary care. Elecsys pTau181 demonstrated a 97.9% negative predictive value (NPV), supporting its utility in ruling out Alzheimer’s pathology and guiding further evaluation.

Fully automated on Roche’s existing lab platforms, the test can be rapidly deployed at scale, potentially reducing delays and expanding access to timely cognitive care. Importantly, the Elecsys test is not diagnostic for Alzheimer’s disease and should be used in conjunction with clinical judgment and existing guidelines. The Alzheimer’s Association emphasizes its role as a “rule-out” tool and supports its integration into broader diagnostic workflows to improve access and efficiency in dementia care.

Sources:

(2025, October 13). Roche Diagnostics. Roche's Elecsys® pTau181 becomes the only FDA-cleared blood test for use in primary care to rule out Alzheimer's-related amyloid pathology [News release]. https://www.prnewswire.com/news-releases/roches-elecsys-ptau181-becomes-the-only-fda-cleared-blood-test-for-use-in-primary-care-to-rule-out-alzheimers-related-amyloid-pathology-302581668.html

(2025, October 13). Alzheimer’s Association. Alzheimer’s Association Welcomes FDA Clearance of First Blood Test for Use in Primary Care to Rule Out Alzheimer’s-Related Amyloid Pathology [News release]. https://www.alz.org/news/2025/fda-clearance-blood-test-primary-care-rule-out-alzheimers-related-amyloid-pathology