FDA approves Alzheimer's blood test for age 40+

The FDA has cleared multiple blood tests to aid in diagnosing Alzheimer's disease. PrecivityAD2, approved for adults 40 and older who are being evaluated for cognitive decline, uses mass spectrometry to measure amyloid and tau proteins and outputs a score indicating the likelihood of brain amyloid deposits, to be interpreted with other clinical information. Separately, Roche and Eli Lilly’s Elecsys pTau217 test, cleared for people 55 and older, detects phosphorylated tau 217 as a biomarker linked to Alzheimer's and is framed as a single-biomarker tool to support both rule-in and rule-out decisions across care settings. Another Roche/Lilly blood test, Elecsys Phospho-Tau, was approved to identify amyloid pathology in older adults and is designed for integration into existing lab networks to broaden access. Roche notes the tests can leverage thousands of Roche analyzers in the U.S., with Labcorp and Quest Diagnostics planning to offer the test through their networks to expand availability, reflecting a push toward simpler, more accessible diagnostic pathways. Taken together, the approvals reflect a broader trend toward blood-based diagnostics that complement imaging and CSF tests and aim to speed and broaden Alzheimer’s evaluation across primary and specialty care settings.