FDA OKs first blood test that can help diagnose Alzheimer’s disease

U.S. health officials endorsed the first blood test that can help diagnose Alzheimer’s and identify patients who may benefit from drugs that can modestly slow the memory-destroying disease.

The test can aid doctors in determining whether a patient’s memory problems are due to Alzheimer’s or a number of other medical conditions that can cause cognitive difficulties. The Food and Drug Administration cleared it for patients 55 and older who are showing early signs of the disease.

More than 6 million people in the United States and millions more around the world have Alzheimer’s, the most common form of dementia.

The new test, from Fujirebio Diagnostics, Inc., identifies a sticky brain plaque, known as beta-amyloid, that is a key marker for Alzheimer’s. Previously, the only FDA-approved methods for detecting amyloid were invasive tests of spinal fluid or expensive PET scans.

The lower costs and convenience of a blood test could also help expand use of two new drugs, Leqembi and Kisunla, which have been shown to slightly slow the progression of Alzheimer’s by clearing amyloid from the brain. Doctors are required to test patients for the plaque before prescribing the drugs, which require regular IV infusions.

For more information see Matthew Perrone "FDA OKs first blood test that can help diagnose Alzheimer’s disease," AP News, May 16, 2025.

Special thanks to Lewis Saret (Attorney, Washington, D.C.) for bringing this article to my attention.