Trialling a blood test for Alzheimer’s disease in UK memory services

Plain English summary of protocol

Background and study aims
This study aims to find out whether plasma p-tau217 helps to diagnose Alzheimer’s disease more quickly at an early disease stage when added to standard UK memory clinic assessments.

Who can participate?
Individuals will be eligible to participate if they are aged 50 years or older, referred by their GP to an NHS memory service, are being seen for their first appointment, have a progressive cognitive complaint reported by themself or their study partner (family member/friend/carer) and are judged by their assessing memory service clinician to have objective impairment with a presentation of either mild cognitive impairment or dementia (mild or moderate, such that they are able to provide informed consent to participate at baseline). Individuals are asked to nominate a study partner who has at least weekly contact with them (family member/friend/carer) who will also be asked to provide informed consent to participate. Individuals who have the capacity to consent at baseline and lose capacity over the course of the study will be eligible to continue participating if they and their study pattern are willing.

What does the study involve?
The location of the study will be sites where patients would normally be referred for assessment of memory problems and would occur at the same time as their normal clinical visits. Individuals will be seen face to face three times over a year (at the start, at 3 months and at 1 year) and will have two telephone-based assessments at 6 and 15 months. As this is part of the normal NHS assessment, no additional travel costs will be incurred. Individuals will be encouraged to attend with a family member, friend or carer as they would do for a normal memory clinic appointment. After the first clinic visit, individuals and their family members/friends/carers will be invited to join the study by their clinicians. Those who consent will donate a blood sample and information about them and their health will be collected. this will add no more than 75 minutes to the standard memory clinic assessment. Individuals and their family members/friends/carers will return to see their doctor to receive a diagnosis at 3 months. At this visit the blood test result will be available to the doctor for half of the patients seen. after the clinic visit the patient and their family member/friend will be invited to be asked some questions about their experience, adding 30 minutes to the assessment. At 6 months the participant and the family member/friend/carer will be contacted by telephone and asked a series of questions, with each call taking no more than 60 minutes. At 12 months individuals and their family member/friend/carer will return for a clinic visit and the blood test result will be available to the clinician for the remaining half of the individuals seen. After the clinic visit, the individual and their family member/friend/carer will be asked some questions, taking no longer than 30 minutes. at 15 months they will have a telephone call similar to that undertaken at 6 months and lasting no more than 60 minutes.

What are the possible benefits and risks of participating?
Participation will mean that the memory service clinician responsible for making a diagnosis has access to the blood test result, which may aid the diagnosis as part of their assessment. There are known risks associated with blood sampling (local pain, bruising, infection) which are managed in accordance with standard clinical practice and local standard operating procedures. There is a risk of psychological distress related to the diagnosis being changed on the basis of the blood test either to or from Alzheimer’s disease. Change of diagnosis is also a possible outcome through clinical follow-up alone (whether or not the blood tests contribute to that change) and so the psychological distress associated with diagnosis or change of diagnosis would be managed according to the standard of care provided by the memory service, which includes referral for post-diagnostic psychological support where deemed appropriate.

Where is the study run from?
The study sponsor is the UCL Comprehensive Clinical Trials Unit (UK). The study will be delivered by the NIHR research delivery network in partnership with NHS trusts across the UK in which memory services are located.

When is the study starting and how long is it expected to run for?
April 2024 to March 2029

Who is funding the study?
1. Alzheimer’s Research UK
2. Alzheimer’s Society (UK)
3. National Institute for Health and Care Research (UK)
4. People’s Postcode Lottery (UK)
5. Gates Ventures

Who is the main contact?
Trial manager, cctu.adapt@ucl.ac.uk

Contact information

Study information

Eligibility

Locations

Countries of recruitment

• United Kingdom
• England
• Scotland

Study participating centres

Results and Publications

Study outputs

Editorial Notes

18/09/2025: The date of first enrolment was changed from 01/08/2025 to 28/08/2025.
18/07/2025: The date of first enrolment was changed from 01/06/2025 to 01/08/2025.
04/04/2025: The recruitment start date was changed from 01/04/2025 to 01/06/2025.
04/12/2024: Study's existence confirmed by the NIHR.