The FDA clearance follows European approval for the test in May.
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The US Food and Drug Administration has cleared Roche and partner Eli Lilly’s blood test to help identify signs of Alzheimer’s disease in people age 55 and older with cognitive decline
The test, Elecsys pTau217, is a biomarker blood test that can help doctors identify patients who are likely or unlikely to have Alzheimer’s-related brain changes, Roche said Monday
The FDA clearance follows European approval for the test in May
The test can be run on more than 4,500 Roche laboratory analyzers already installed across the United States, which the company said could help broaden access. Labcorp and Quest Diagnostics have said they plan to offer the test through their laboratory networks, potentially expanding availability
Roche did not disclose the test’s price
The FDA clearance comes as drugmakers and diagnostic companies race to develop simpler tests for Alzheimer’s disease to meet growing demand for earlier diagnosis and treatment
Fujirebio’s Lumipulse became the first blood test cleared by the FDA to aid in the assessment of Alzheimer’s disease in 2025. Roche and Lilly’s Elecsys pTau181 test, which measures a different protein than the newly cleared test, also received the FDA’s green light last year. Last week, the agency cleared C2N Diagnostics’ Precivity AD2 test
Traditionally, diagnosing Alzheimer’s required expensive and invasive procedures like PET scans or spinal taps. However, blood tests that measure levels of the biomarker phosphorylated tau 217, or p-tau217, “strongly predict” the buildup of sticky beta-amyloid plaques in the brain, Rachel Buckley, an associate professor of neurology at Harvard Medical School, told CNN earlier this year
The amyloid plaques, which trigger inflammation and damage communication between neurons, can collect in the brain decades before memory loss or cognitive decline — even when people are in their 30s and 40s
As beta-amyloid levels rise in the brain, tangles of proteins called tau begin gathering inside brain cells, causing neurons to collapse and die. In some diseases such as frontal lobe dementia, which damages executive function instead of memory, tangles can accumulate without the presence of amyloid
Not everyone with high levels of amyloid will progress to dementia, just as having tau in the brain does not dictate cognitive impairment later in life, Buckley said
Elecsys pTau217 is not intended to be used as a standalone diagnostic test, and results should be interpreted alongside other clinical information, Roche said
“Single ‘Alzheimer’s blood tests’ can be fraught with challenges, and this new test is no different,” Alzheimer’s prevention researcher Dr. Richard Isaacson, director of research at the Institute for Neurodegenerative Diseases in Florida, told CNN in an email Monday
“Just like when a doctor orders a cholesterol test, do they ever order only 1 test? No – they order a panel of tests and that is the strategy that I advocate for to minimize confusion and improve clinical diagnostic and risk prediction accuracy.”
Isaacson noted that the new test “has a sufficient negative predictive value (likelihood that it rules out a diagnosis of Alzheimer’s disease correctly)” but says the “positive predictive value is not great.”
“False positive tests are a problem in clinical practice so we need to be careful (especially with a new test like this that has both positive, negative AND indeterminate classifications),” he wrote. Trouble with the way samples are handled or the presence of other medical conditions such as kidney problems or viral illnesses can also lead to confusion with interpreting the results
Instead of using p-tau217 and amyloid blood tests for diagnosis, Isaacson runs them to look for clues on how people are responding to treatment and lifestyle changes
Personalized lifestyle interventions such as an improved diet, exercise, sleep and socialization — combined with the management of insulin, cholesterol and other risk factors as needed — have reduced amyloid and tau levels in patients dedicated to improving their health
“Research is now showing up to 45% of dementia cases can be prevented with lifestyle interventions such as exercise, diet, social engagement, cognitive training, and management, vascular and metabolic risk factors,” Laura Nisenbaum, interim chief science officer at the Alzheimer’s Drug Discovery Foundation, which funds Alzheimer’s research, told CNN earlier this year
Reuters contributed to this report
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