Overview
- The U.S. Food and Drug Administration has cleared C2N Diagnostics' PrecivityAD2 for use in adults aged 40 and older who show signs of cognitive impairment; the test is meant to be used with a clinical assessment rather than as a standalone screen.
- PrecivityAD2 uses high‑resolution mass spectrometry to measure plasma amyloid and phosphorylated tau and reports an amyloid probability score (APS2) that combines p‑tau217 and Aβ42/40 ratios to estimate brain amyloid pathology.
- C2N reported strong validation results from 1,142 symptomatic participants, with a 97.6% positive predictive value to rule in amyloid and a 93.1% negative predictive value to rule out amyloid when compared with amyloid PET or cerebrospinal fluid benchmarks.
- The test is currently offered as a lab‑developed test and C2N says the formally FDA‑cleared commercial version is expected to become available later in 2026; clinicians are advised to order it only when experienced in evaluating cognitive impairment.
- Longstanding funding from the Alzheimer's Drug Discovery Foundation, including a $7 million Diagnostics Accelerator investment, helped move blood biomarkers from research to clinics and the clearance is likely to speed biomarker‑based trial screening and earlier, more targeted care for patients.