In most people with Alzheimer’s disease, the clinical symptoms appear later in life. A key sign of the disease is the buildup of amyloid plaques in the brain. These can be detected using amyloid PET scans, often years before symptoms begin. However, PET scans are expensive, time-consuming, and involve radiation exposure. That’s where the new blood test comes in.

The Lumipulse G pTau217/β-Amyloid 1-42 Plasma ratio test measures two proteins, pTau217 and β-amyloid 1-42, found in human plasma, a component of blood. It calculates a ratio linked to the presence of amyloid plaques in the brain, and slashes the need for PET scans. Unlike earlier tests that require a spinal tap to collect cerebrospinal fluid, this new test only needs a simple blood draw, making it less invasive and easier for patients.