The U.S. Food and Drug Administration (FDA) has granted clearance for reportedly the first in vitro diagnostic device that uses a blood sample to aid in diagnosing Alzheimer’s disease. The Lumipulse G pTau217/ß-Amyloid 1-42 Plasma Ratio test is now approved for marketing. It is intended for adult patients aged 55 years and older who are showing signs and symptoms of cognitive decline.
The device measures levels of two proteins found in human plasma — pTau217 and β-amyloid 1-42 — and calculates their ratio. This ratio is associated with the presence or absence of amyloid plaques in the brain, a known marker for Alzheimer’s disease. Traditionally, these plaques are detected through amyloid PET brain scans or cerebrospinal fluid (CSF) tests, both of which can be invasive, expensive, and time-consuming. The new blood-based test is designed to reduce reliance on these procedures.
“Alzheimer’s disease impacts too many people, more than breast cancer and prostate cancer combined,” said FDA Commissioner Martin A. Makary, M.D., M.P.H. “Knowing that 10 per cent of people aged 65 and older have Alzheimer’s, and that by 2050 that number is expected to double, I am hopeful that new medical products such as this one will help patients.”
The test is designed for patients in a specialised care setting, where it can be used alongside other clinical evaluations to determine the probable cause of cognitive symptoms. It is not meant to be used as a screening tool or a standalone diagnostic method.
Clinical data submitted to the FDA included results from a multi-centre study involving 499 cognitively impaired adults. The test outcomes were compared with amyloid PET scans and CSF test results. In the study, 91.7 per cent of patients with positive Lumipulse results were confirmed to have amyloid plaques, and 97.3 per cent of those with negative results were confirmed not to have them. Fewer than 20 per cent of the tested patients received an indeterminate result.
The FDA highlighted that false positives could lead to an incorrect diagnosis and unnecessary treatment, while false negatives could delay appropriate care and cause additional testing. The Lumipulse test is intended to be used in conjunction with a broader clinical assessment.
“Nearly 7 million Americans are living with Alzheimer’s disease and this number is projected to rise to nearly 13 million,” said Michelle Tarver, M.D., Ph.D., Director of the Center for Devices and Radiological Health. “Today’s clearance is an important step for Alzheimer’s disease diagnosis, making it easier and potentially more accessible for U.S. patients earlier in the disease.”
The test was reviewed through the FDA’s 510(k) premarket notification pathway, which allows new devices to be cleared by demonstrating substantial equivalence to an existing legally marketed device. The Lumipulse G pTau217/ß-Amyloid 1-42 Plasma Ratio was found to be substantially equivalent to the previously authorised Lumipulse G β-amyloid Ratio (1-42/1-40), which uses CSF samples.
Fujirebio Diagnostics, received the FDA’s Breakthrough Device designation for this blood test, enabling expedited development and regulatory review.
