On 31 March 2025, an international team of researchers from the USA, Sweden & the Netherlands published findings in Nature Medicine supporting the use of a new blood biomarker to detect tau pathology in Alzheimer’s disease (AD). The study, titled Plasma MTBR-tau243 biomarker identifies tau tangle pathology in Alzheimer’s disease, evaluated a form of tau protein in blood plasma known as eMTBR-tau243. This biomarker reflects the presence of tau tangles—abnormal accumulations of tau protein that are a core feature of AD and closely linked to symptoms. Across three independent cohorts (n = 108, 55 and 739), the researchers found that plasma levels of eMTBR-tau243 were significantly elevated in people with mild cognitive impairment and even higher in those with dementia.
The marker strongly correlated with both tau positron emission tomography (PET) imaging (β = 0.72) as well as cognitive performance (β = 0.60) and outperformed existing plasma tau biomarkers (p-tau217 and p-tau205). The results suggest that eMTBR-tau243 could offer a simple, cost-effective alternative to PET scans for detecting tau pathology, supporting diagnosis, prognosis & treatment monitoring in both research and clinical settings. This is a relevant advance, as tau imaging is currently expensive & not widely accessible. A blood-based biomarker that reliably reflects tau pathology could improve early detection and support efforts to evaluate therapies targeting tau in AD. The article has been published open access and can be read here:
