AIBRIEF
C2N's PrecivityAD2 reads brain amyloid from a blood draw, not a spinal tap, as new disease modifying drugs make earlier confirmation actionable.
The FDA cleared PrecivityAD2, a blood test that helps clinicians evaluate whether a patient has the brain amyloid plaques linked to Alzheimer's disease. The developer, C2N Diagnostics, uses high-resolution mass spectrometry, not the immunoassay chemistry behind other recently cleared blood tests, to return quantitative biomarker readings (WashU Source announcement).
The timing is what turns the clearance into a clinical event. Lecanemab and donanemab, the first drugs that can measurably slow Alzheimer's progression, work better when started earlier. A less invasive route to confirming amyloid turns a piece of information that was largely academic into something a symptomatic patient can act on with their doctor (WashU Medicine on blood vs spinal-fluid performance).
The test aids evaluation rather than acting as a standalone Alzheimer's diagnosis; results are meant to be read alongside clinical history and other diagnostics. C2N's underlying technology was co-developed at Washington University in St. Louis, where researchers including Randall Bateman have separately published on detecting and staging Alzheimer's from blood (Bateman and Horie recognized for staging method).
Other FDA-cleared immunoassay blood tests for amyloid are already on the market. The announcement does not address price, insurance coverage, or the intended-use population in detail (Alzheimer's Association announcement).