FDA Clears New Blood Test for Alzheimer’s Diagnosis

The Food and Drug Administration (FDA) has approved a new blood test called PrecivityAD2 to assist in diagnosing Alzheimer’s disease. Developed by C2N Diagnostics, this test targets adults aged 40 and older who show symptoms of cognitive impairment.

This blood test is designed to be used alongside clinical evaluations. It is not intended as a standalone test or screening tool. C2N Diagnostics announced it as the first FDA-cleared test for symptomatic adults 40 and older.

Alzheimer’s, the leading form of dementia, affects 60 to 80 percent of dementia patients, according to the Alzheimer’s Association. Currently, around 7.4 million Americans aged 65 and older live with Alzheimer’s, with projections estimating that number could reach 13.8 million by 2060.

The disease progresses over time. After a diagnosis, patients typically live between four to eight years, though some might live up to 20 years. A 2026 study in the journal Alzheimer’s & Dementia indicated a 134 percent increase in reported Alzheimer’s deaths between 2000 and 2024.

How Is Alzheimer’s Currently Detected?

Alzheimer’s disease is linked to the accumulation of proteins like beta-amyloid and tau in the brain. These proteins are believed to damage nerve cells, leading to symptoms such as memory loss, personality changes, and struggles with daily tasks.

Healthcare professionals diagnose Alzheimer’s by assessing a patient’s symptoms, sometimes consulting family members. Early signs include memory loss, poor concentration, poor judgment, mood changes, communication difficulties, and confusion. Clinicians may then perform laboratory tests and imaging scans for further evaluation.

How Does the Blood Test Work?

C2N Diagnostics’ test detects beta-amyloid plaques in the brain, providing data to inform clinical assessments. In clinical validation studies with over 1,000 participants, it showed a 97.6 percent positive predictive value and a 93.1 percent negative predictive value.

The test is effective at identifying amyloid plaques in patients with varying degrees of cognitive impairment.

Dr. Joel Braunstein, Co-Founder and CEO of C2N, stated: “The FDA clearance is a significant milestone for our company, the Alzheimer’s community, and the field of molecular diagnostics.”

What Does This Mean for Alzheimer’s?

C2N’s test offers quicker and less invasive results compared to PET scans. Recent studies show that using multiple biomarker tests can reduce the time needed for initiating amyloid-targeting treatments. This new blood test could accelerate diagnosis and treatment for patients.