UK trial launches to transform Alzheimer’s diagnosis with simple blood test

A major clinical trial aiming to transform the diagnosis of Alzheimer’s disease through a simple blood test, is now welcoming its first participants who will be recruited via memory clinics across the UK.

The ADAPT study

The ADAPT (Alzheimer's Disease Diagnosis and Plasma p-Tau217) team, led by Professor Jonathan Schott and Dr Ashvini Keshavan at University College London (UCL), is evaluating whether a test measuring the protein p-tau217 in blood can help to diagnose Alzheimer’s disease earlier and more accurately than current methods.  

The first ADAPT trial location began recruitment in Essex Partnership University NHS Foundation Trust on 28 August 2025 with 19 additional specialist NHS Centres planned across the UK. 

The trial will examine whether providing the blood test results to patients and their clinicians near the start of an assessment for memory and thinking concerns is able to aid diagnosis and guide decisions on further investigations and treatments. The study will recruit participants through NHS memory services and will include people from diverse geographic, ethnic and economic backgrounds, and those living with other health conditions to ensure the findings are relevant and inclusive of the broader population. 

Blood Biomarker Challenge

This landmark trial forms part of the Blood Biomarker Challenge, a multi-million-pound programme funded by Alzheimer’s Society, Alzheimer’s Research UK and players of People’s Postcode Lottery. The initiative aims to determine if the blood test is accurate and reliable in a broad range of patients that would make it a trusted form of diagnostics in comparison with current methods.  

Alzheimer’s disease, the most common cause of dementia, is linked to the build-up of two key proteins in the brain called amyloid and tau. One of the most promising biomarkers in the blood, p-tau217, reflects the presence of both amyloid and tau in the brain. Emerging evidence suggests that blood tests such as plasma p-tau217 can detect these proteins as accurately as current methods such as amyloid PET scans and lumbar punctures.

Although these blood tests are not standalone diagnostic tools, they could be used as part of as a wider clinical assessment to confirm the diagnosis of Alzheimer’s disease for people who already have memory or thinking problems. As a blood test has the potential to offer a less invasive, more accessible, and cost-effective alternative to current specific tests for Alzheimer’s (PET scans or lumbar punctures), proving their utility in clinical practice could enable earlier and more equitable access to both diagnosis and future treatments across the NHS.

What is the Blood Biomarker Challenge?

With an estimated third of people living with dementia currently undiagnosed, there is a clear need to improve the speed and accuracy of dementia diagnosis. Alzheimer's Society is hoping to achieve this through the Blood Biomarker Challenge.

Find out more

What's happening next?

The ADAPT team have already assessed and validated the accuracy and performance of the p-tau217 blood test which is now established in the National Hospital for Neurology and Neurosurgery's NHS clinical laboratory. The team are now conducting a clinical trial aiming to provide evidence that the test is accurate, cost-effective and should be part of the standard of care more widely in NHS memory services.

The ADAPT study will recruit individuals who are referred to memory services with either mild progressive memory problems or early dementia. All participants will receive standard diagnostic assessments and care. Of the 1,100 planned participants, half will receive their blood test results within three months of being assessed for the first time in their memory service, while the other half will receive theirs after 12 months.

The team will assess whether providing results earlier helps speed up the diagnosis, guide decisions about further investigations, and influences how both patients and clinicians interpret and respond to the results. 

Researchers will also assess the impact of blood test results on quality of life using a system called the EQ-5D-5L, a standardised instrument for measuring health-related quality of life, as well as healthcare costs, and their relevance to people from diverse ethnic backgrounds or with conditions like kidney disease.

Professor Jonathan Schott, Professor of Neurology at University College London, and Chief Medical Officer at Alzheimer’s Research UK, said: 

“We are thrilled to welcome participants onto the ADAPT trial  – a critical part of the Blood Biomarker Challenge, which we hope will take us a step forward in revolutionising the way we diagnose dementia."

“After decades of research, we now have a blood test for Alzheimer’s disease that is backed by strong scientific evidence and provides comparable information to other gold-standard diagnostic tests such as PET scans and lumbar punctures yet is far more accessible, and cheaper. 

“Currently only about 2% of people diagnosed with Alzheimer’s have access to one of these gold-standard diagnostic tests."

"While identifying Alzheimer’s disease early and accurately is already important for enabling access to current therapies and planning care, it will become even more critical as a new generation of treatments emerge that can slow down the decline of memory and thinking. Timely diagnosis will be key to ensuring these advances reach the people who need them most.”  

Working together to improve dementia diagnosis

Professor Fiona Carragher, Chief Policy and Research Officer at Alzheimer’s Society, said: 

Too often, dementia is diagnosed late, limiting access to support, treatment, and opportunities to plan ahead. A timely and accurate diagnosis also enables participation in research, including clinical trials. For many families across the UK, getting that diagnosis remains a major challenge.

“The launch of the ADAPT trial marks a critical step in changing that. Blood tests could offer a faster and more accessible route to diagnosis. The Blood Biomarker Challenge is committed to building the evidence needed to bring these innovative tests into NHS care, delivering real benefits for people living with dementia and their families.”

Dr Sheona Scales, Director of Research at Alzheimer’s Research UK, added: 

Today, one in three people with dementia do not have a diagnosis. The ADAPT trial is an important opportunity to change this and transform the way dementia is diagnosed across the UK. It shows how sustained investment in research is leading to breakthroughs in dementia.

Voices from the ADAPT group

Members of the ADAPT Patient and Public Involvement (PPI) group share their hopes for the impact of the Blood Biomarker Challenge on people affected by dementia:

Michael White, who cares for his wife Kathryn, said:

“At the moment it feels a bit like we have no effective medicine, and this is because we have no accurate diagnosis. Hopefully initiatives like the Blood Biomarker Challenge will pave the way to change.

Steven Pidwell, who cares for his wife Rachel, said: 

Having a diagnosis of Alzheimer’s disease does not mean the end. There is hope and that is what we must remember.

Take part in dementia research

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