FDA Clears First Blood Test to Rule Out Alzheimer-Related Amyloid Pathology

The US Food & Drug Administration (FDA) has cleared the first blood test to rule out Alzheimer-related amyloid pathology, announced by Roche Diagnostics on October 13, 2025. The Elecsys pTau181 test, intended for patients aged ≥ 55 years with presenting Alzheimer Disease symptoms, can assist the initial assessment for Alzheimer Disease and other causes of cognitive decline in the primary care setting.

Created in partnership with Eli Lilly and Company, this minimally invasive test offers clinicians insights to help detect patients in the early stages of cognitive decline who are unlikely to have Alzheimer-related amyloid pathology. The test detects phosphorylated Tau (pTau) 181 protein in human plasma, a critical biomarker associated with Alzheimer Disease pathology, including amyloid plaque and tau aggregates. However, even with this test, clinicians should still interpret results with other clinical data.

“By bringing Alzheimer's blood-based biomarker testing into primary care, we can help patients and their clinicians get answers sooner to support them earlier in their journeys,” said Brad Moore, president and CEO of Roche Diagnostics North America. “This milestone reflects Roche’s leadership in diagnostics and our commitment to expanding access to innovative testing for patients and their clinicians.”

Alzheimer Disease affects 7 million Americans and has numerous pathologies. Approximately 92% of patients with mild cognitive impairment remain undiagnosed, preventing them from considering potential therapeutic interventions.

To date, Alzheimer’s biomarker testing has been confined to specialty settings, such as neurology clinics. By bringing testing into primary care, the Elecsys pTau181 test has the potential to increase patient access to minimally invasive diagnostics while allowing specialists to focus on patients most likely to need advanced evaluation. With over 4,500 Roche instruments already installed in clinical laboratories across the United States, providers can easily integrate the Elecsys pTau181 test into their practice.

Investigators assessed the performance of the Elecsys pTau181 test in a multicenter, non-interventional clinical study involving 312 participants. The study showed that, in an early disease stage, the test could rule out Alzheimer Disease pathology with a 97.9% negative predictive value.

With FDA clearance, the Elecsys pTau181 test may help healthcare providers assess patients with cognitive complaints early, rule out Alzheimer-related amyloid pathology, better integrate primary care into the diagnostic pathway, guide referrals, preserve specialist resources, and reduce reliance on more invasive, costly procedures such as PET scans and CSF testing.

Beyond FDA clearance in the United States, Roche recently earned CE Mark certification in Europe for the Elecsys pTau181 test, making it the first blood test certified under the In Vitro Diagnostic Regulation to aid in ruling out Alzheimer-related amyloid pathology.

References

Roche’s Elecsys® pTau181 becomes the only FDA-cleared blood test for use in primary care to rule out Alzheimer’s-related amyloid pathology. Diagnostics. Published October 6, 2025. Accessed October 13, 2025. https://diagnostics.roche.com/us/en/news-listing/2025/fda-cleared-ptau181-alzheimers-blood-test.html