NHS trials £100 blood test in bid to revolutionise Alzheimer’s diagnosis

Doctors have launched a clinical trial of a £100 blood test for Alzheimer’s, aiming to speed up diagnosis of the condition within the NHS.

More than 1,000 patients with suspected dementia are being recruited from memory clinics across the UK to test whether the approach provides quicker and more reliable results, and improves care for those diagnosed.

Over half a million people in the UK have Alzheimer’s, the most common form of dementia, yet a confirmed diagnosis can take years.

Only about 2 per cent of patients receive a gold-standard diagnosis based on a PET scan or a lumbar puncture – where spinal fluid is extracted to detect hallmarks of the disease.

Although drugs such as lecanemab and donanemab can slow progression, their effect is limited and they have been rejected for broad NHS use by the National Institute for Health and Care Excellence (Nice). Attention has now shifted to a new generation of drugs under trial.

These treatments are most effective when given early, before irreversible brain damage occurs.

A simple blood test could allow doctors to identify patients who stand to benefit most.

Prof Jonathan Schott is a neurologist at University College London and co-lead on the Adapt trial.

He said: “We’re expecting numerous further treatments to come on stream within the next 10 years, so we need to prepare the National Health Service now, to be able to deliver these treatments, as well as the benefits an accurate diagnosis already gives.”

Alzheimer’s disease is linked to the build-up of two proteins in the brain, amyloid and tau.

The blood test measures p-tau217, a protein that reflects the presence of both. Evidence suggests it can detect them as reliably as PET scans and lumbar punctures.

The Adapt trial is enrolling 1,100 people from varied geographic, ethnic and economic backgrounds, including those with other health problems, to ensure findings reflect the wider UK population.

Half of participants will receive their blood test results within three months of assessment, while the other half will wait 12 months.

Doctors will then assess whether earlier access to results improves the speed and quality of diagnosis and guides treatment decisions.

Specialist laboratories using the test can currently return results in around two weeks.

Dr Ashvini Keshavan is a senior clinical research fellow at University College London’s Dementia Research Centre and co-lead on the trial.

Keshavan said: “This is not about confirming accuracy, which we have already done.

“This is about showing that it actually makes a difference to patients’ onward management.”

Recruitment is expected to take two years.

If results are promising, they will be presented to Nice to decide whether the test should be introduced across the NHS.

The trial is part of the Blood Biomarker Challenge, a multimillion-pound programme supported by the Alzheimer’s Society, Alzheimer’s Research UK and the People’s Postcode Lottery.

Dr Sheona Scales, director of research at Alzheimer’s Research UK, said: “We know that the drug development pipeline for Alzheimer’s disease is currently burgeoning with new potential treatments.

“The earlier we can intervene with these experimental or new potential treatments, the greater their chances of success.

“So the science is currently moving fast, there is a pace of change, but we need the diagnosis in order to speed up, in order to help us to unlock this.”