The US Food and Drug Administration recently approved the first blood test to aid in the diagnosis of Alzheimer’s disease. This new test aims to reduce dependency on PET scans, offer a less invasive alternative, and improve accessibility to diagnosis. It quantifies blood levels of the proteins tau and amyloid-beta and is less invasive than the spinal tap currently used to detect these proteins in cerebrospinal fluid.
According to estimates, about 32 million people worldwide are living with Alzheimer’s, the most common type of dementia [1]. In the US alone, about 7 million people have Alzheimer’s, and this number is expected to rise to approximately 13 million by 2050 [2].
As with any condition, the sooner Alzheimer’s disease is diagnosed, the better the outcome. This is partly because the drugs that are currently available for the disorder help treat its symptoms and possibly delay its progression.
Currently, Alzheimer’s diagnosis involves an evaluation that includes a patient’s medical history, cognitive examination, PET or MRI brain imaging, and laboratory testing to look for the proteins tau and amyloid-beta in a sample of cerebrospinal fluid (CSF).
Even with these methods, diagnosing Alzheimer’s can be challenging, particularly in its early stages. Furthermore, many people find the existing variety of gold-standard diagnostics, such as amyloid PET scans and CSF tests, to be invasive and challenging to access.
To enhance the early detection of Alzheimer’s, the U.S. FDA recently approved Fujirebio Diagnostics, Inc.’s Lumipulse G pTau217/ß-Amyloid 1-42 Plasma Ratio as the first blood test to aid in the diagnosis of the illness [3].
The Lumipulse blood test is easier to perform and less invasive than spinal taps and brain scans. It may assist in identifying whether cognitive impairment and memory loss are due to Alzheimer’s and may give patients early access to presently approved medications for the condition. Although other blood tests have been used to screen people for clinical trials related to Alzheimer’s, this is the first FDA-approved test.
Here’s everything you need to know about this new non-invasive blood test for early Alzheimer’s detection.
How does the Lumipulse blood test for Alzheimer’s work?
The new test takes a simple blood sample to examine plasma, a component of blood. The FDA’s news release states that the Lumipulse blood test measures the levels of beta-amyloid 1-42 and pTau 217 in blood plasma [3].
The Lumipulse G pTau217/β-Amyloid 1-42 Plasma Ratio test measures the concentration ratio of two proteins to assess the presence of amyloid plaques in the brain, a key indicator of Alzheimer’s disease.
Toxic beta-amyloid can build up in the brain for up to 20 years before Alzheimer’s symptoms manifest. When protein levels rise, they cluster together to create hard, rough amyloid plaques in the spaces between the cells, suffocating healthy brain cells. Later on, the tau protein starts to build up and create tangles inside neurons that interfere with the neurons’ ability to communicate with other brain cells.
How is this test different from other Alzheimer’s blood tests on the market?
Until now, detecting amyloid plaque formation has required either a PET scan, which is expensive and not widely available, or a lumbar puncture to collect cerebrospinal fluid (CSF). The new blood test gives doctors a more straightforward and less invasive way to assess if a patient’s cognitive or memory issues are due to Alzheimer’s or another type of dementia.
Other available blood tests, such as the PrecivityAD® test and ALZpath Dx™, employ similar methodologies to determine Alzheimer’s risk by measuring the amyloid-beta and tau proteins. These tests are accessible in the United States as laboratory-developed tests, which means they can be used in certified labs under specific regulatory guidelines. However, Lumipulse is the first to get FDA approval for helping diagnosis.
Can anybody get the blood test?
Individuals without symptoms should not undergo testing, as it is not intended to serve as a screening test for healthy people. The Lumipulse Test is for early identification of Alzheimer’s-related amyloid plaques in individuals aged 55 and above who show symptoms of the disease.
Alzheimer’s experts at memory clinics or other specialized care settings should administer the test. Experts should evaluate the results in light of other clinical patient information, such as memory and neurologic test results.
Is the test result conclusive?
The test isn’t entirely accurate. It may indicate Alzheimer’s, but further testing, such as spinal taps or PET brain scans, might be required to help confirm a diagnosis.
Researchers collected plasma samples from 499 individuals with cognitive impairment at various medical centers and compared the Lumipulse blood test results to those from CSF samples and PET brain scans. PET scans and CSF test results verified the presence of amyloid plaques in over 92% of those who tested positive on the Lumipulse blood test. Over 97 percent of patients with negative Lumipulse blood test results also had negative CSF or PET scan results for amyloid.
Results were not always conclusive. In the Lumipulse blood test, less than 20% of the 499 individuals received indefinite results.
Does the test have any risks?
There are no significant health risks associated with the test itself because it only involves a simple blood draw. Nevertheless, a small percentage of individuals may receive a positive test result but not genuinely have Alzheimer’s disease (false positives).
According to the FDA, when combined with other clinical data, false positive results may result in an incorrect diagnosis and unnecessary treatment of Alzheimer’s. This may result in psychological discomfort, a delay in a proper diagnosis, unnecessary treatment costs, and the possibility of adverse effects.
A smaller percentage of individuals may receive a negative Lumipulse test result but have Alzheimer’s (false negatives). According to the FDA, false negative results may lead to further unnecessary diagnostic testing and possibly delay effective treatment.
Who can benefit from the blood test?
The test can assist in determining whether symptoms like memory loss and other issues are due to Alzheimer’s or another type of dementia, such as Lewy body dementia or vascular dementia. It might also help identify which patients would benefit from the more recent Alzheimer’s medications that target beta-amyloid accumulation in the brain, including Kisunla and Leqembi.
Lumipulse results may also aid in ruling out Alzheimer’s. Memory issues can also be caused by another medical condition, such as a tumor or stroke, or as a side effect of some medications.
How much does the test cost, and does your insurance cover it?
The test is currently being rolled out and is likely to become more widely available in the coming months. The medicine manufacturer has not yet disclosed the final cost, but it is anticipated to be between $500 and $1,000, which is significantly less costly than a spinal tap or PET scan. Since the FDA has approved it, Medicare and other insurance plans are expected to cover it.
The Lumipulse test’s FDA approval is a significant step toward broader insurance reimbursement, including potential Medicare coverage. Regulatory approval allows the Centers for Medicare & Medicaid Services to start assessing the test for reimbursement. It might make testing more accessible, especially to older persons who are most impacted by Alzheimer’s. Patients’ out-of-pocket expenses, however, are yet unknown and can change based on physician charges, individual insurance plans, and lab processing fees.
Additionally, blood tests like Lumipulse are anticipated to be crucial in determining whether patients can benefit from new treatments for Alzheimer’s disease, especially those that target amyloid buildup.
What’s next for Alzheimer’s testing?
The Lumipulse blood test is the first to get clearance by the FDA. However, other blood tests are in development, some of which target other indicators, such as levels of inflammation in the brain. As doctors gain more experience with the blood test and new tests become available, they may be able to provide more personalized treatments for Alzheimer’s patients.
Alzheimer’s Research Association is a non-profit organization dedicated to helping caregivers of Alzheimer’s disease and dementia. We provide the latest information and news about the illness and helpful tips to help caregivers cope with their daily caregiving challenges. We realize the most important thing that a caregiver needs is financial assistance. Therefore, we provide grants to caregivers to ease their financial burden. Caregivers can apply for grants here: Alzheimer’s Grant Application.
You can also help caregivers in their endeavor by donating as much as possible: Donation To Alzheimer’s Research Associations.
References
- Gustavsson, A., Norton, N., Fast, T., Frölich, L., Georges, J., Holzapfel, D., Kirabali, T., Krolak‐Salmon, P., Rossini, P.M., Ferretti, M.T. and Lanman, L., 2023. Global estimates on the number of persons across the Alzheimer’s disease continuum. Alzheimer’s & Dementia, 19(2), pp.658-670.
- Alzheimer’s Disease Facts and Figures. Alzheimer’s Association. https://www.alz.org/alzheimers-dementia/facts-figures. Accessed: 30 May, 2025.
- FDA Clears First Blood Test Used in Diagnosing Alzheimer’s Disease. FDA News Release. U.S. Food & Drug Administration. https://www.fda.gov/news-events/press-announcements/fda-clears-first-blood-test-used-diagnosing-alzheimers-disease. Published Online: 16th May, 2025. Accessed: 30th May, 2025.
- Pelc, C. First blood test for Alzheimer’s gets FDA greenlight: 3 things to know. Medical News Today. https://www.medicalnewstoday.com/articles/first-blood-test-alzheimers-gets-fda-greenlight-3-things-to-know. Published Online: 22nd May, 2025. Accessed: 30st May, 2025.
- What to know about the new blood test for Alzheimer’s. Fisher Center for Alzheimer’s Research Foundation. https://www.alzinfo.org/articles/diagnosis/what-to-know-about-the-new-blood-test-for-alzheimers/. Published Online: 28th May, 2025. Accessed: 30st May, 2025.
- Findley, C. FDA Clears First Blood Test to Aid in Alzheimer’s Diagnosis. Alzheimer’s Disease Research, A BrightFocus Foundation Program. https://www.brightfocus.org/news/fda-clears-first-blood-test-to-aid-in-alzheimers-diagnosis/. Published Online: 22nd May, 2025. Accessed: 30st May, 2025.
- Spichak, S. The First FDA-Approved Alzheimer’s Blood Test: What You Need to Know. Being Patient. https://www.beingpatient.com/fda-approved-alzheimers-blood-test/. Published Online: 20th May, 2025. Accessed: 30st May, 2025.
