NCT06889896

Brief Summary

Background: Blood-based biomarkers show promise in predicting Alzheimer's disease (AD) pathology and progression; however, inconsistencies in detection standards hinder clinical application. A head-to-head comparison of commercially available biomarkers is crucial for optimizing the clinical pathway for AD screening and diagnosis. Method: The CLEAR-AD study is an ongoing population-based cross-sectional study, currently recruiting 400 participants in ten centers in China. The study includes cognitively normal controls, individuals with mild cognitive impairment (MCI) - categorized as amyloid-positive and amyloid-negative - as well as patients with dementia, also divided into amyloid-positive and amyloid-negative groups. All participants undergo amyloid PET scans using tracers such as AV1, AV45, and PIB. Blood samples are collected within three months prior to the PET scan or from existing samples collected after January 1, 2024, that meet quality standards. After collection, these samples are analyzed at a central laboratory under blinded conditions using multiple detection methods to measure plasma levels of Aβ40, Aβ42, t-tau, and p-tau181/217. The detection technologies included single-molecule immunoassay, digital immunoassay chips, magnetic particle chemiluminescence, and flow cytometry fluorescence. The objective is to assess the sensitivity and specificity of different plasma biomarker levels in predicting amyloid pathology confirmed by Aβ-PET. Result: The study uses Aβ-PET as the reference standard to evaluate the sensitivity and specificity of various AD plasma biomarkers across different detection methods in diagnosing amyloid pathology. The analysis included generating receiver operating characteristic (ROC) curves, determining optimal cut-off values, and developing a predictive model that integrates multiple biomarker parameters and clinical data. Results is considered statistically significant with a p-value of less than 0.05.

Trial Health

55
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
400

participants targeted

Target at P75+ for all trials

Timeline
Completed

Started Jul 2024

Geographic Reach
1 country

1 active site

Status
enrolling by invitation

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

July 11, 2024

Completed
8 months until next milestone

First Submitted

Initial submission to the registry

March 17, 2025

Completed
4 days until next milestone

First Posted

Study publicly available on registry

March 21, 2025

Completed
2 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

June 1, 2025

Completed
2 months until next milestone

Study Completion

Last participant's last visit for all outcomes

August 1, 2025

Completed
Last Updated

March 21, 2025

Status Verified

June 1, 2024

Enrollment Period

11 months

First QC Date

March 17, 2025

Last Update Submit

March 17, 2025

Conditions

Outcome Measures

Primary Outcomes (1)

  • Evaluate the sensitivity and specificity of blood biomarkers in predicting amyloid pathology confirmed by Aβ-PET under different testing methods

    2025.08

Study Arms (5)

AD

There are clear complaints of cognitive impairment, and the diagnoses of AD meet the NIA-AA 2011 diagnostic criteria.

Diagnostic Test: After Blood samples collection, these samples are analyzed at a central laboratory under blinded conditions using multiple detection methods to measure plasma levels of Aβ40, Aβ42, t-tau, and p-tau

MCI(Aβ PET+)

There are clear complaints of cognitive impairment, and the diagnoses of MCI meet the NIA-AA 2011 diagnostic criteria. Amyloid protein PET indicated positive within the last 3 months."

Diagnostic Test: After Blood samples collection, these samples are analyzed at a central laboratory under blinded conditions using multiple detection methods to measure plasma levels of Aβ40, Aβ42, t-tau, and p-tau

MCI(Aβ PET-)

There are clear complaints of cognitive impairment, and the diagnoses of MCI meet the NIA-AA 2011 diagnostic criteria.Amyloid protein PET indicated negative within the last 3 months

Diagnostic Test: After Blood samples collection, these samples are analyzed at a central laboratory under blinded conditions using multiple detection methods to measure plasma levels of Aβ40, Aβ42, t-tau, and p-tau

Non-AD dementia

Non-AD dementia is defined as patients who have a decline in cognitive abilities but are diagnosed with dementia due to other reasons (including but not limited to FTD, DLB, VD, PDD, etc.

Diagnostic Test: After Blood samples collection, these samples are analyzed at a central laboratory under blinded conditions using multiple detection methods to measure plasma levels of Aβ40, Aβ42, t-tau, and p-tau

Cognitively normal controls

No complaints of cognitive impairment, scores within the normal range, and amyloid protein PET negative

Diagnostic Test: After Blood samples collection, these samples are analyzed at a central laboratory under blinded conditions using multiple detection methods to measure plasma levels of Aβ40, Aβ42, t-tau, and p-tau

Interventions

The CLEAR-AD study is an ongoing population-based cross-sectional study, currently recruiting 400 participants in ten centers in China. The study includes cognitively normal controls, individuals with mild cognitive impairment (MCI) - categorized as amyloid-positive and amyloid-negative - as well as patients with dementia, also divided into amyloid-positive and amyloid-negative groups. All participants undergo amyloid PET scans using tracers such as AV1, AV45, and PIB. Blood samples are collected within three months prior to the PET scan or from existing samples collected after January 1, 2024, that meet quality standards. After collection, these samples are analyzed at a central laboratory under blinded conditions using multiple detection methods to measure plasma levels of Aβ40, Aβ42, t-tau, and p-tau181/217. The detection technologies included single-molecule immunoassay, digital immunoassay chips, magnetic particle chemiluminescence, and flow cytometry fluorescence. The objective i

ADCognitively normal controlsMCI(Aβ PET+)MCI(Aβ PET-)Non-AD dementia

Eligibility Criteria

Age45 Years - 85 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)
Sampling MethodNon-Probability Sample
Study Population

The CLEAR-AD study is an ongoing population-based cross-sectional study, currently recruiting 400 participants in ten centers in China. The study includes cognitively normal controls, individuals with mild cognitive impairment (MCI) - categorized as amyloid-positive and amyloid-negative - as well as patients with dementia, also divided into amyloid-positive and amyloid-negative groups. All participants undergo amyloid PET scans using tracers such as AV1, AV45, and PIB.

You may qualify if:

  • Patient Group (including MCI, AD, and Non-AD Dementia):
  • Clear complaints of cognitive impairment, with MCI and AD diagnoses meeting the NIA-AA 2011 diagnostic criteria. Non-AD dementia is defined as patients with cognitive decline diagnosed with dementia due to other reasons (including but not limited to FTD, DLB, VD, PDD, etc.).
  • Able to provide informed consent or have a legal guardian who can sign the consent form.
  • Completed a full set of cognitive assessments, including MMSE and CDR.
  • Able to provide a history of chronic diseases, including cardiovascular diseases, diabetes, etc., and medication history.
  • Have undergone amyloid protein PET scans that meet the quality requirements of this study (tracers PiB, AV1, or AV45), and can provide original imaging data for quantitative analysis without conflict.
  • Can provide frozen plasma from a biobank collected after January 1, 2024, with a time interval of ≤3 months from the amyloid protein PET scan. If no frozen plasma is available, willing to provide an additional 5ml of whole blood for biomarker testing in this project. The process of blood collection, plasma separation, storage, and transportation meets the quality requirements of this study (see blood testing SOP).
  • Have 3D-T1 structural MRI images taken within 3 months before and after the amyloid protein PET scan and can provide original imaging data without conflict.
  • Normal Control Group:
  • Subjects with a CDR score of 0 and who have undergone amyloid protein PET scans that are negative.
  • Able to provide informed consent.
  • Completed a full set of cognitive assessments, including MMSE and CDR.
  • Able to provide a history of chronic diseases, including cardiovascular diseases, diabetes, etc., and medication history.
  • Have undergone amyloid protein PET scans that meet the quality requirements of this study (tracers PiB, AV1, or AV45), and can provide original imaging data for quantitative analysis without conflict.
  • Can provide frozen plasma from a biobank collected after January 1, 2024, with a time interval of ≤3 months from the amyloid protein PET scan. If no frozen plasma is available, willing to provide an additional 5ml of whole blood for biomarker testing in this project. The process of blood collection, plasma separation, storage, and transportation meets the quality requirements of this study (see blood testing SOP).
  • +1 more criteria

You may not qualify if:

  • History of Mental Illness:\*\* Depression (Geriatric Depression Scale \[GDS\] \> 7 points or Hamilton Depression Rating Scale \[17-item version\] \> 7 points);
  • History of Central Nervous System Diseases:\*\* Including infections, epilepsy, multiple sclerosis, toxic metabolic diseases, familial hereditary diseases, neurotumors, etc.;
  • Severe Stroke Sequelae:\*\* mRS \> 3 points or a documented history of stroke sequelae;
  • Severe Liver and Kidney Dysfunction at Diagnosis:\*\* ALT ≥ 5 times the upper limit of normal, or estimated glomerular filtration rate (eGFR) \< 30 ml·min-¹·(1.73 m²)-¹, or patients requiring renal replacement therapy;
  • History of Drug Abuse and Severe Alcoholism;\*\*
  • Prior Use of Anti-Aβ or Other Disease-Modifying Treatments,\*\* unless there is clear evidence of a placebo group;
  • Severe Hyperlipidemia:\*\* Triglycerides ≥ 5.6 mmol/L or visible chylomicron changes in plasma.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China

Hefei, Anhui, 230000, China

Location

Biospecimen

Retention: SAMPLES WITH DNA

Peripheral blood plasma and blood cells

Study Design

Study Type
observational
Observational Model
OTHER
Time Perspective
CROSS SECTIONAL
Sponsor Type
OTHER GOV
Responsible Party
SPONSOR

Study Record Dates

First Submitted

March 17, 2025

First Posted

March 21, 2025

Study Start

July 11, 2024

Primary Completion

June 1, 2025

Study Completion

August 1, 2025

Last Updated

March 21, 2025

Record last verified: 2024-06

Data Sharing

IPD Sharing
Will not share

All interested researchers can obtain relevant information through the contact details of the researchers

Locations