Today, people who suspect they have Alzheimer’s disease tend to undergo invasive, uncomfortable, and costly brain scans or spinal taps before they receive a diagnosis. By then, symptoms have already begun to surface, offering them and their families less time to make necessary healthcare and lifestyle adjustments. But what if doctors could spot Alzheimer’s in patients before they begin to experience memory loss?
That’s the idea behind a new blood test made by ALZpath, a California-based medical diagnostics company. Called the ALZpath pTau217 assay, the test is currently available exclusively to research entities, who are busy verifying the test’s efficacy with people at risk of developing Alzheimer’s. In a study examining the results of three Alzheimer’s study cohorts, researchers at Sweden’s University of Gothenburg found that the pTau217 assay is highly accurate and could be ready for clinical research soon.
Rather than requiring patients to undergo brain scans or spinal taps, the pTau217 assay simply requires a small blood sample. It searches this sample for phosphorated tau 217, or p-Tau217, a variant of the tau protein. Tau and amyloid β-protein (Aβ) are known to accumulate in the brains of people with Alzheimer’s, making them both valuable biomarkers when it comes to Alzheimer’s diagnosis; however, p-tau217 tends to outperform other Alzheimer’s-related biomarkers when blood plasma is the testing medium.
The University of Gothenburg’s longitudinal study found that the pTau217 assay correctly identified elevated levels of tau 97% of the time, making it an incredibly accurate diagnostic tool. The test also tracked participants’ p-Tau217 levels as they increased over the years, allowing for “improved patient management and, ultimately, timely access to disease-modifying therapies,” the researchers note.
The pTau217 assay isn’t the first Alzheimer’s-focused blood test. A year ago, scientists at the University of Washington announced SOBA, a test that looks for clumps of Aβ in blood samples. Another test, AD-Detect, was also made available to consumers last year, though it can’t be used for diagnosis purposes; it can only help people assess their risk of developing Alzheimer’s disease.
Many other Alzheimer’s diagnosis and treatment options are underway, too. An electroencephalography (EEG) headband developed in 2023 appears to reliably monitor users for signs of the disease by spotting brain wave “spindles.” A drug produced by pharmaceutical giant Eli Lilly could help delay the onset of severe Alzheimer’s symptoms, while a peptide engineered at MIT might minimize symptom occurrence. Last year, a common bodybuilding supplement was identified as a potential agent against cognitive decline. And to prevent memory loss in the first place, an international team of researchers is working on developing an Alzheimer’s vaccine.
