Blood-based biomarker tests the new frontier for Alzheimer’s diagnosis

Blood-based tests are emerging as valuable tools for the early detection of Alzheimer’s disease, offering accessible alternatives to PET scans and cerebrospinal fluid (CSF) analysis. With Alzheimer’s disease affecting over 55 million people globally, and cases projected to triple by 2050, advances in diagnostic methods are critical for timely intervention. These tests could make diagnosis faster, less invasive, and more affordable. However, questions remain about their real-world impact on patient outcomes, according to GlobalData.

Ashley Clarke, Senior Medical Analyst at GlobalData, comments, “Blood-based biomarker tests represent a major leap forward in diagnostics. There has been a transformative shift in other conditions like heart attacks, where troponin tests are now widely used as a cost-effective, efficient path to early assessment. For Alzheimer’s disease, reliable and accessible testing could lead to earlier detection, giving patients more time to pursue interventions and lifestyle changes.”

In the US, the FDA is yet to grant full approval to blood-based Alzheimer’s tests, but breakthrough devices are showing high diagnostic accuracy. For example, C2N Diagnostics’ PrecivityAD has demonstrated 90  per cent accuracy in identifying Alzheimer’s disease in symptomatic patients, providing a simpler alternative to PET scans.

More than 150 in vitro diagnostic tests for Alzheimer’s disease are currently in development, according to GlobalData’s Pipeline Products Database, with many aiming to address gaps in early detection. Another device, Roche’s Elecsys amyloid plasma panel, recently showed a negative predictive value of 96.2  per cent in Phase II trials, suggesting a strong potential to rule out Alzheimer’s disease.

Clarke adds, “With high negative predictive values, blood-based tests could serve as reliable screening tools, helping reserve hospital resources for procedures such as PET scans for patients most likely to need them.”

GlobalData reports that at least five pipeline devices are now in the regulatory approval process across the US and Europe, yet ethical and regulatory challenges persist. These tests raise concerns about overdiagnosis, exposure of sensitive health data, and the potential for insurers to adjust premiums based on test outcomes. Predictive testing also introduces ethical considerations around informed consent, and potential psychological impacts for patients learning their risks in a disease still lacking a cure.

Clarke concludes, “Blood-based tests for Alzheimer’s have the potential to transform how we diagnose this disease, making it easier and less invasive for patients. By ensuring these tests are accurate and ethically implemented, we can enhance early detection, reduce healthcare costs, and ultimately improve outcomes for families navigating the challenges of Alzheimer’s disease.”

Edits made by EH News Bureau