A new blood test that could help detect Alzheimer’s disease earlier has been approved for use in the UK. Roche is working closely with two early-adopter sites in the UK and Ireland to enable rapid patient access.
Elecsys pTau217 is a blood test that measures the phosphorylated Tau (pTau) 217 protein, an indicator of amyloid pathology and a hallmark of Alzheimer’s disease. The standalone blood-based biomarker (BBBM) was developed in collaboration with Eli Lilly and Company and can be used to help rule in or rule out Alzheimer’s in people over 55 presenting with symptoms of cognitive decline, using the same thresholds across primary and specialist care settings.1,2,4,5
In the UK, it is estimated that one million people are living with a form of dementia, with this projected to rise to 1.4 million by 2040. Around one in three people living with dementia in the UK do not have a diagnosis, and those who are diagnosed wait on average around three and a half years after symptoms first appear.6
Identifying the changes linked to Alzheimer’s disease early is critical for accurate diagnosis and timely access to care and treatment. The approval of the Elecsys pTau217 blood test is based on data1,2,5 from retrospective studies in real-world populations, including people at the earliest stages of the disease - such as those experiencing mild memory problems but who are still living independently.
These early stages, often described as subjective cognitive decline or mild cognitive impairment, are when symptoms first emerge but can be difficult to diagnose with certainty. By enabling detection at this point, the test can help determine whether Alzheimer’s-related changes are present earlier in the patient pathway.
A confirmed diagnosis can help individuals and their families understand the cause of symptoms, access appropriate support, and plan next steps. It may also enable access to treatments shown to slow disease progression, which are currently being reassessed for NHS use by the National Institute for Health and Care Excellence.
“The CE Mark for Elecsys pTau-217 marks a significant milestone for patients in the UK who are experiencing cognitive symptoms”, said Peter Hampson, Head of Medical Affairs UK and Ireland at Roche Diagnostics.
“Alzheimer’s remains one of the greatest and most urgent health challenges we face today, affecting millions of people and placing growing pressure on families and health systems. With no cure currently available, earlier and more accurate diagnosis is increasingly critical.
“For many people, the journey to an Alzheimer’s diagnosis can be long, distressing, and filled with uncertainty. People shouldn’t be left in limbo for months or years, not knowing what’s happening to them. This blood test could help people get answers sooner, when it really matters.”
Brain scans and CSF tests that are currently used to diagnose Alzheimer’s can be expensive, difficult to access, and invasive.7 By contrast, the Elecsys pTau217 blood test offers a simpler way to detect signs of the disease, helping to identify people who might otherwise go undiagnosed.1,2
References
1. www.sciencedirect.com/science/article/pii/S2274580726000580?via%3Dihub
2. pmc.ncbi.nlm.nih.gov/articles/PMC12805464/
3. https://www.ucl.ac.uk/news/2025/jul/dementia-takes-35-years-diagnose-after-symptoms-begin
4. https://alz-journals.onlinelibrary.wiley.com/doi/10.1002/alz.13859
6. dementiastatistics.org/about-dementia/prevalence-and-incidence/
