A Study to Assess Regional Cerebral Blood Flow as an Alzheimer's Disease Biomarker Compared to Positron Emission Tomography in Patients With Mild-to-Moderate Alzheimer's Disease and Cognitively Normal Elderly Subjects (Study MK-0000-068)(COMPLETED)

Study Overview
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Brief Summary
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The aim of the study is to determine if regional cerebral blood flow, measured by dynamic arterial spin labeling (dASL), can be a biomarker for stage of Alzheimer's disease. The study is designed to be conducted in 2 parts in participants with mild to moderate Alzheimer's disease, and participants with normal cognition. Various imaging studies will be done using magnetic resonance imaging (MRI) and positron emission tomography (PET) along with neurocognitive assessments. Participants who meet the study-entry criteria will have up to 8 study visits. Repeat imaging studies may be required if the initial data are incomplete or un-interpretable. The maximum number of PET scans during the study will be limited to four.

Official Title
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A Two-Part Cross-Sectional and Longitudinal Study to Assess Regional Cerebral Blood Flow by Dynamic Arterial Spin Labeling as an Alzheimer's Disease Biomarker as Compared to FDG-PET in Patients With Mild-to-Moderate Alzheimer's Disease and Cognitively Normal Elderly Subjects

Conditions
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Alzheimer's Disease

Intervention / Treatment
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* Other: MRI
* Other: FDG-PET


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The prospective participant must meet, at least, all of the criteria below (among others determined by the study staff) to be eligible for study participation. The participant: Has mild-to-moderate Alzheimer's Disease (AD), OR is considered cognitively normal; Has been on stable doses of any regularly used medications for 4 weeks prior to study start; Must have been on a stable dose for 12 weeks prior to study start, of any medications taken for AD. Exclusion Criteria: If the prospective participant meets any of the criteria below (among others determined by the study staff) they will NOT be eligible for study participation. The participant: Is living in a nursing home or skilled nursing facility; Has severe AD; Cannot undergo MRI; Cannot undergo PET scans; Has a history of neurological or neurodegenerative disorders, other than AD within 2 years prior to study start; Has taken Tacrine or anti-parkinsonian medications within 3 months of study start; Has taken corticosteroids, blood thinners, narcotic analgesics, benzodiazepines, or certain antihistamines within 1 month of study start; Initiates, discontinues, or changes the dose of any AD treatment during the study.

Ages Eligible for Study
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Minimum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: AD Participants<br>Participants with a diagnosis of mild-to-moderate AD | Other: MRI<br>* During the study all participants will have 4 total MRI scans: baseline, 1 week, 6 and 12 months.<br>Other: FDG-PET<br>* 2 to 4 PET scans will be done over 12 months, 2 planned and 2 more if data from any of these are un-interpretable<br>|
| Experimental: Cognitively Normal Elderly Participants<br>Elderly participants with no cognitive impairment | Other: MRI<br>* During the study all participants will have 4 total MRI scans: baseline, 1 week, 6 and 12 months.<br>Other: FDG-PET<br>* 2 to 4 PET scans will be done over 12 months, 2 planned and 2 more if data from any of these are un-interpretable<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Regional cerebral blood flow, as measured by dASL. | Part I: regional cerebral blood flow, measured by dASL at Baseline and 1 week in AD participants and cognitively normal controls. Part II: regional cerebral blood flow, measured at 6 months and 12 months in AD participants and normal control participants. | 1 week, 6 and 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of cerebral glucose consumption, MRglc, as measured by fludeoxyglucose-PET (FDG-PET) | Regional cerebral rate of glucose consumption, MRglc, as assessed by FDG-PET will be measured at Baseline in (Part I) and at 12 months in (Part II), in AD participants and normal control participants. | 12 months | 
| Resting state functional MRI blood-oxygen-level-dependent (fMRI BOLD) response | The resting state fMRI BOLD (blood-oxygen-level-dependent) signal will be evaluated for 'Goodness-of-Fit' to the default mode network at Baseline, 1 week, and 6 and 12 months in AD participants and normal control participants. | 1 week, 6 and 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Alzheimer's Disease, MRI, PET