FDA Clears First Single-Biomarker Blood Test for Alzheimer

The FDA cleared the first and only single-biomarker blood test for assessing amyloid pathology to rule in or rule out Alzheimer disease in adults aged 55 and older.¹

The Elecsys Phospho-Tau (217P) Plasma (pTau217) blood test, developed by Roche in partnership with Eli Lilly, addresses the need for noninvasive, value-based testing for early Alzheimer detection. Traditional approaches such as positron emission tomography (PET) imaging and cerebrospinal fluid (CSF) testing are costly and difficult to access for many patients. An estimated 75% of people living with dementia remain undiagnosed, highlighting the potential for a single-biomarker blood test to broaden access and improve the rate of diagnosis—when used in conjunction with other diagnostic tools—thus providing patients with clarity and an earlier diagnosis.¹

"Advances in blood-based biomarkers have the potential to transform the diagnostic pathway by expanding access to evaluation for Alzheimer's across a variety of care settings," said Jared R. Brosch, MD, neurologist, Indiana University Health, in a press release. "As these tools become available, clinicians may be able to evaluate more patients earlier in the disease course, improving diagnostic confidence and helping patients and their families make more informed decisions at a critical time."

How the Blood Test Detects Amyloid Pathology

The test is designed to detect phosphorylated tau 217 (p-tau217), a biomarker of Alzheimer disease pathology that reflects changes associated with amyloid and tau accumulation.^2,3 When evaluated in adults aged 55 and older with signs, symptoms, or complaints of cognitive decline, the blood test demonstrated high agreement with amyloid PET imaging.¹

The single-biomarker strategy, paired with one set of validated clinical cutoffs, is what Roche refers to as the "Power of One"—as it simplifies Alzheimer assessment and expands access to blood-based testing.¹

"For millions of families navigating the uncertainty of Alzheimer's disease, a timely diagnosis is the first and most critical step toward meaningful care," Carole Ho, MD, executive vice president and president of Lilly Neuroscience, said in a press release.

The blood test also has the potential to aid clinical decision-making across primary and specialty care, specifically by supporting the clinical assessment of amyloid pathology. It would help identify next steps after distinguishing patients with a high or low likelihood of amyloid pathology and who should be considered for further testing. It could also help optimize the current diagnostic pathway, further aiding clinicians in determining the next treatment or testing steps.¹

"For decades, clinicians have faced significant challenges in accurately diagnosing Alzheimer's disease in its early stages," Brosch said in a press release. "While PET imaging and cerebrospinal fluid biomarkers can confirm amyloid pathology in patients with cognitive impairment, these approaches may be costly, invasive, and not readily accessible for many patients."

Broad Laboratory Access Could Speed Rollout

The instruments designed to run the blood test—Roche's Cobas laboratory analyzers—are already installed at more than 4500 clinical laboratories across the US, positioning the test for rapid integration into existing workflows without requiring additional instrumentation.¹

"As the first and only FDA-cleared, single-biomarker blood test supporting both rule-in and rule-out assessment of amyloid pathology, Elecsys pTau217 has the potential to transform how Alzheimer's is assessed across primary and specialty care," said Dan Malarek, president and CEO of Roche Diagnostics North America, in a press release. "This kind of innovation can help bring diagnostic evaluation closer to patients and give clinicians greater confidence in determining the right step in their care."

References

1. Roche receives FDA clearance for Elecsys pTau217, advancing Alzheimer’s disease assessment across primary and specialty care. Roche. News release. August 24, 2026. Accessed August 25, 2026. https://diagnostics.roche.com/us/en/news-listing/2026/fda-elecsys-ptau217-alzheimers-blood-test.html https://diagnostics.roche.com/us/en/news-listing/2026/fda-elecsys-ptau217-alzheimers-blood-test.html

2. Schindler SE, Galasko D, Pereira AC, et al. Acceptable performance of blood biomarker tests of amyloid pathology—recommendations from the Global CEO Initiative on Alzheimer’s Disease. Nat Rev Neurol. 2024;20:426-439. doi:10.1038/s41582-024-00977-5

3. Adams B. Roche, Eli Lilly net FDA approval for first-of-its-kind Alzheimer’s biomarker blood test. Fierce Biotech. August 24, 2026. Accessed August 25, 2026. https://www.fiercebiotech.com/medtech/roche-eli-lilly-see-fda-approval-first-its-kind-alzheimers-biomarker-blood-test