A new kind of test for Alzheimer’s disease is available in the United States after receiving approval earlier this month.
The U.S. Food and Drug Administration permitted marketing of an in vitro test for Alzheimer’s meant to detect protein rations that can determine the presence of amyloid plaque in the brain, a hallmark of Alzheimer’s. The new test could function as an alternative to costly PET scans.
The IV test, formally called the Lumipulse G β-Amyloid Ratio (1-42/1-40) test, is the first of its kind for Alzheimer’s. Made and marketed by Japanese IV technology specialist Fujirebio, it can be conducted on pre-existing Fujirebio equipment. It’s intended to be used on patients 55 and older to determine if cognitive impairment in an individual could be related to Alzheimer’s.
Jeff Shuren, MD, director of the Center for Devices and Radiological Health at the FDA, said in a press release that the new test can be a faster alternative to PET scans to help diagnose Alzheimer’s without radiation.
“The availability of an in vitro diagnostic test that can potentially eliminate the need for time-consuming and expensive PET scans is great news for individuals and families concerned with the possibility of an Alzheimer’s disease diagnosis,” he said. “With the Lumipulse test, there is a new option that can typically be completed the same day and can give doctors the same information regarding brain amyloid status, without the radiation risk, to help determine if a patient’s cognitive impairment is due to Alzheimer’s disease.”
…there is a new option that can typically be completed the same day…without the radiation risk, to help determine if a patient’s cognitive impairment is due to Alzheimer’s disease.
The new test works, as the name suggests, by comparing the levels of two proteins – beta-amyloid 1-42 and beta-amyloid 1-40 – to determine the likelihood of beta-amyloid plaque in the brain. In clinical trials, 97% of positive tests with the IV method were also positive with PET scans, and 84% of negative tests also showed up negative with the PET scan.
The FDA does warn that the main risk associated with the test is a false negative or false positive result. Both the FDA and the manufacturer maintain that other factors must be considered when diagnosing Alzheimer’s, and that the test result alone is not enough to diagnose Alzheimer’s.
“The Lumipulse G β-Amyloid Ratio (1-42/1-40) test is not intended as a screening or standalone assay to diagnose AD,” reads Fujirebio’s statement on the approval. “Results must be interpreted in conjunction with other patient clinical information. The assay is analyzed on Fujirebio’s fully automated LUMIPULSE G1200 instrument system, which is available to clinical laboratories nationwide.”