Alzheimer's Blood Tests and UK Research Trials: What Families Need to Know in 2026

A New Chapter in Dementia Diagnosis

For anyone who has watched a loved one navigate the long, often uncertain road to a dementia diagnosis, news of a simple blood test that could detect Alzheimer's disease earlier and more accurately is genuinely exciting. In 2026, that possibility feels closer than ever, thanks to a major UK research programme that is already under way.

At the same time, it is worth being clear about where things actually stand. Blood tests for Alzheimer's are not yet a routine part of NHS care, and a single test cannot diagnose every form of dementia. This guide explains what the science currently shows, what trials are happening, and what to do if you are concerned about your own memory or that of someone close to you.

What Is the p-tau217 Blood Test?

Alzheimer's disease, the most common cause of dementia, is linked to the build-up of two key proteins in the brain: amyloid and tau. Researchers have been working hard to find ways to detect these proteins without invasive procedures, and one particular marker called p-tau217 has emerged as especially promising.

A blood test measuring p-tau217 can reflect the presence of both amyloid and tau in the brain. Emerging evidence suggests it can detect these proteins as accurately as current diagnostic methods, such as amyloid PET scans and lumbar punctures, which are costly, specialist and, in the case of lumbar punctures, uncomfortable for patients.

The appeal is clear. A blood test is less invasive, far more accessible and potentially much cheaper. If it can be shown to work reliably in a wide range of real-world patients, it could one day allow people to receive a faster, clearer diagnosis and, crucially, access any appropriate treatments sooner.

That said, even a highly accurate blood test is not a standalone diagnostic tool. It would be used as part of a broader clinical assessment, alongside a person's symptoms, medical history and, in some cases, other investigations.

The Blood Biomarker Challenge: A Landmark UK Trial

The most significant UK development right now is the Blood Biomarker Challenge, a programme funded by Alzheimer's Society, Alzheimer's Research UK and players of People's Postcode Lottery, with additional support from the National Institute for Health and Care Research (NIHR) and Gates Ventures. It is an £8 million-plus initiative designed to bring dementia blood tests to the NHS by 2029.

Within this programme, the ADAPT trial (Alzheimer's Disease Diagnosis and Plasma p-Tau217) is being led by Professor Jonathan Schott and Dr Ashvini Keshavan at University College London. Their team is evaluating whether measuring p-tau217 in blood can help diagnose Alzheimer's earlier and more accurately than current methods, and whether it performs reliably across a broad range of patients who present in everyday NHS settings, not just those recruited through specialist research centres.

This is an important distinction. Research studies have already shown strong accuracy for p-tau217 in controlled settings. The ADAPT trial aims to confirm whether those results hold up across the fuller, more diverse population that NHS memory services actually see. That kind of real-world evidence is exactly what is needed before a test can be rolled out routinely.

Is an Alzheimer's Blood Test Available on the NHS Now?

Not routinely, no. As of late 2026, p-tau217 blood testing remains within the research setting in the UK. It is not something you can currently request from your GP as a standard diagnostic test.

What the NHS does offer is a well-established pathway for anyone with memory or thinking concerns. Your GP can assess your symptoms, carry out initial cognitive tests, and refer you to a local memory clinic or specialist service if needed. Memory clinics can then access more detailed assessments, brain imaging and specialist input. For many people, this pathway works well, and advances in blood testing are intended to make it even more effective, not to replace it.

If and when the Blood Biomarker Challenge trials generate sufficient evidence, the ambition is to make blood testing part of the standard NHS diagnostic toolkit, potentially as early as 2029. That would be a transformative step forward.

Could You or a Family Member Take Part in a Trial?

Research trials in this area often recruit adults aged 55 and over who are being seen in memory services or who have concerns about their memory. Eligibility for any specific study will vary, and not everyone who is interested will qualify.

If you think a family member might be suitable, the best starting point is their GP or memory clinic team. You can also find information about current studies on the NIHR Be Part of Research website or through the Alzheimer's Society and Alzheimer's Research UK. It is important not to assume that being over 55 automatically makes someone eligible for any particular trial: each study has its own inclusion criteria, which may include things like existing symptoms, prior diagnoses or geographical location.

Participating in research is a genuinely valuable thing to do, and many people find it a positive experience. But it is entirely voluntary and separate from the care and support available through the NHS.

What Should You Do If You Are Worried About Memory?

If you or someone you care about has noticed changes in memory, thinking or day-to-day functioning, the right first step is always to speak to a GP. Do not wait for a blood test to become available, and do not try to interpret any research news as a substitute for clinical assessment.

Your GP can:

• Talk through the symptoms and what might be causing them
• Carry out or arrange initial cognitive assessments
• Refer to a memory clinic if further investigation is needed
• Signpost relevant support organisations

The NHS 111 service is also available if you need urgent guidance outside of GP hours.

Early conversations with a GP matter, whatever a person's age or situation. Many conditions that affect memory are treatable, and getting an accurate picture early gives families more time to plan and access support.

Living Well at Home While You Wait for Clarity

For families navigating an uncertain period before or after a diagnosis, it is worth knowing that practical support does not have to wait. At Hedgerow Homecare, we work with many families across North London who are managing the early stages of memory change, helping people stay safe, comfortable and connected at home.

Our dementia care in North London is tailored to each individual, with a small, consistent team of carers who get to know the person well. Alongside that, our companionship care and elderly care services can provide meaningful day-to-day support that makes a real difference to wellbeing. For families thinking further ahead, our respite care can give family carers a much-needed break while their loved one continues to be well looked after at home.

Bringing care back home is at the heart of what we do, and for many families, staying in familiar surroundings is exactly what helps most during a time of change.

Looking Ahead with Optimism

The progress being made on Alzheimer's blood tests is genuinely encouraging. UK researchers at UCL and beyond are doing important work, and the Blood Biomarker Challenge represents a well-funded, collaborative effort to bring meaningful advances into everyday NHS care.

The science is moving quickly, and 2026 is a real moment of momentum. For families, the most useful thing right now is to stay informed, speak to a GP if you have concerns, and know that good support is available today, whatever the future of diagnostics brings.

For general information about dementia research and support, the Alzheimer's Society website is an excellent resource.

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If you would like to talk through care options for someone living with dementia or memory change in North London, the team at Hedgerow Homecare is happy to help. Get in touch to arrange a free care assessment, with no obligation.

Hedgerow Homecare Editorial Team