Alzheimer’s Blood Test Becomes First FDA-Cleared Option for Adults as Young as 40

S. Food and Drug Administration (FDA) on August 20, 2026, for adults as young as 40 who are experiencing signs of cognitive impairment, according to the Alzheimer’s Drug Discovery Foundation (ADDF). The authorization makes PrecivityAD2 the first FDA-cleared Alzheimer’s blood test available to patients in this younger age group. The decision reflects accelerating progress in bringing scalable blood-based diagnostics into mainstream care.

PrecivityAD2 represents the latest milestone in a long-running collaboration between the ADDF and C2N Diagnostics. According to the ADDF, the partnership began in 2008 with early seed funding that helped catalyze development of PrecivityAD, which the foundation describes as the first blood test designed to aid in the diagnosis of Alzheimer’s disease. The ADDF has continued to support C2N, including through a USD 7 million investment from its Diagnostics Accelerator (DxA), as part of broader efforts to establish blood-based biomarkers as a cornerstone of modern Alzheimer’s research and care.

The ADDF noted that Alzheimer’s pathology can start 15 to 20 years before symptoms, and validated tools that reach patients earlier help pave the way for earlier detection. The organization said today’s action follows the FDA’s clearance of Fujirebio’s Lumipulse blood test, another ADDF-funded diagnostic, and comes as the foundation maintains a diagnostics portfolio of 47 active programs across seven pathways. Its stated priorities include advancing next-generation biomarkers such as blood tests for tau and other mixed pathologies, multi-marker panels, artificial intelligence–driven approaches, and diagnostics that reflect the broader pathobiology of disease.

“PrecivityAD2 reflects how far biomarker science has come, and it points to an even bigger opportunity ahead,” said Laura Nisenbaum, PhD, Interim Chief Science Officer at the ADDF.

“Tests like this don't just help to diagnose Alzheimer's, they can also identify the right patients for a clinical trial and confirm whether a drug is engaging its target. That kind of precision is already reshaping trial design: 83% of active Alzheimer's trials now incorporate a biomarker. As we validate the next generation of tools, we will move closer to the same transformative approach already common in cancer care: being able to match the right drugs to the right patient at the right time,” said Nisenbaum.

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