FDA Clears First Blood Test to Aid Alzheimer’s Diagnosis, Ushering in New Era of Early Detection

By: Carl Schwartzbaum

In a decision hailed as a turning point in the battle against neurodegenerative disease, the U.S. Food and Drug Administration (FDA) has granted marketing clearance to the first-ever blood test designed to aid in the diagnosis of Alzheimer’s disease. As CNN reported, the newly approved test—developed by Pennsylvania-based Fujirebio Diagnostics Inc.—represents a significant leap forward in early detection and access to care, potentially transforming how Alzheimer’s is identified and treated across the United States.

Known as the Lumipulse G pTau217/ß-Amyloid 1-42 Plasma Ratio, the test measures the presence of two hallmark proteins in the blood—phosphorylated tau 217 (pTau217) and beta-amyloid 1-42. While it does not directly detect amyloid plaques in the brain, which are considered a definitive feature of Alzheimer’s pathology, it provides a reliable biomarker-based ratio that correlates with the presence or absence of these plaques. This allows clinicians to make earlier and more accurate assessments of patients aged 55 and older who exhibit signs and symptoms of the disease.

As the CNN report highlighted, this FDA approval comes amid growing pressure on the healthcare system to meet the demands of an aging population, with the number of Americans aged 65 and older projected to double by 2050. Alzheimer’s disease already affects over 6 million Americans and accounts for more deaths annually than breast and prostate cancer combined.

“This clearance by the FDA is monumental,” said Dr. Martin Makary, the agency’s commissioner, in Friday’s announcement. “Alzheimer’s disease impacts too many lives. I am hopeful that new medical products such as this one will help patients get the care they need earlier.”

According to data reviewed by the FDA and reported by CNN, clinical trials for the blood test involved plasma samples from 499 adults with cognitive impairment. When compared to the gold-standard PET scans or cerebrospinal fluid (CSF) testing, the Lumipulse test showed promising accuracy: 91.7% of positive blood test results were confirmed by PET or CSF scans, while 97.3% of negative results corresponded to negative amyloid findings via more invasive diagnostics.

These findings signal a major advancement over traditional diagnostic methods. Currently, diagnosing Alzheimer’s often requires costly PET scans or invasive spinal taps. “This is a much simpler screening test with reasonable accuracy,” said Dr. Richard Isaacson, a preventive neurologist interviewed by CNN. Isaacson, who helped establish one of the nation’s first Alzheimer’s prevention clinics, noted that the blood test could now be used in clinical settings to provide much-needed clarity for patients and physicians alike.

Still, experts caution that this is not a standalone diagnostic. As CNN notes, the FDA emphasized that the blood test should be used in conjunction with other clinical information, including patient history, neurological exams, and cognitive evaluations. Dr. Isaacson added that while the clearance is an important milestone, “we need to advance education about what these tests mean and what they don’t.”

Perhaps most notably, CNN reported that the approval could democratize access to Alzheimer’s diagnostics. PET scans often cost thousands of dollars and are not always covered by insurance. Blood-based testing, on the other hand, offers a far more affordable and scalable alternative.

Monte Wiltse, president and CEO of Fujirebio Diagnostics, described the test’s FDA clearance as the culmination of years of research aimed at improving early detection. “An early and accurate diagnosis will also facilitate the development of new drug therapies,” Wiltse said in a news release. Given the projected rise in Alzheimer’s cases globally, earlier detection could be vital in managing the disease before irreversible damage occurs.

Alzheimer’s experts quoted by CNN—including Dr. Howard Fillit of the Alzheimer’s Drug Discovery Foundation—view the development as transformative. “The ability to diagnose Alzheimer’s earlier with a simple blood test, like we do for cholesterol, is a game changer,” Fillit said. “It allows more patients to receive treatment options that have the potential to significantly slow or even prevent the disease.”

Despite its promise, the new test introduces critical questions regarding when, and for whom, such testing should be offered. Dr. Maria Carrillo, chief science officer at the Alzheimer’s Association, cautioned that “important questions for health care professionals to consider” remain unanswered—particularly around test interpretation, psychological impacts of early diagnosis, and integration into care pathways.

According to the information provided in the CNN report, several laboratory-developed and experimental blood tests have already been in use under research exemptions. However, this is the first to receive FDA clearance, potentially setting a precedent for future diagnostics.

“This marks a major milestone,” said Carrillo. “Blood-based biomarkers are reshaping how we identify and understand Alzheimer’s disease.” At the same time, the approval signals the need for updated clinical guidelines, ethical safeguards, and insurance reimbursement protocols.

As CNN concluded, while the Lumipulse test is not a diagnostic silver bullet, its FDA approval offers unprecedented potential to expand early detection of Alzheimer’s disease.