PET Imaging of Phosphodiesterase-4 (PDE4) in Volunteers With Alzheimer s Disease (AD) or Mild Cognitive Impairment (MCI)
National Institute of Mental Health (NIMH)
Summary
Background: About 5 million adults in the United States have age-related brain disorders. These include Alzheimer disease (AD), mild cognitive impairment (MCI), and other dementias. The number of people with these disorders will likely increase as the population ages and life span increases. Inflammation is thought to play a role in AD and MCI. Researchers want to know if an enzyme called PDE4B increases inflammation in people with AD or MCI. Objective: To test whether medical imaging using a new radiotracer (\[18F\]PF-06445974) can measure PDE4B in the brains of people with AD or MCI. Eligibility: People aged 50 years and older with AD or MCI. Healthy volunteers are also needed. Design: Participants will have up to 5 clinic visits with 3 imaging scans of the brain. They will have be screened. They will have a physical exam with blood tests. This will include tests of their heart and nerve function, including memory. Participants will have 2 positron emission tomography (PET) scans. One will use a standard radiotracer. The other will use the study radiotracer. They will receive each tracer through a tube attached to a needle inserted into a vein. During the scan with the study tracer, participants will have a second tube inserted into a vein in the wrist; this tube will be used to draw blood during the scan. Participants will lie on a bed that slides into a doughnut-shaped machine. These visits will take about 6 hours each. Participants will have 1 magnetic resonance imaging (MRI) scan. They will lie on a bed that slides into a cylinder. This visit will take up to 2 hours....
Description
Study Description: As a biomarker of neuroinflammation, the density of PDE4B is hypothesized to be elevated in individuals with AD or MCI compared to age-matched healthy volunteers (HVs). Participants will receive two positron emission tomography (PET) scans (for PDE4B and for beta-amyloid (A beta)) and one magnetic resonance imaging (MRI) scan of the brain. Objectives: Primary Objective: To determine whether PDE4B radioligand binding is increased in medial temporal lobe of participants with AD or MCI (both A beta positive) compared to age-and sex matched HVs (who are A beta negative) Exp…
Eligibility
- Age range
- 50–100 years
- Sex
- All
- Healthy volunteers
- Yes
* INCLUSION CRITERIA: Participants will be referred by a physician with the suspected diagnosis of AD or MCI. However, the PI of this protocol will provide the final diagnosis. For this reason, this protocol will have just one consent form for participants suspected of having either AD or MCI. AD and MCI Study Groups: Participants must meet all the following criteria: * Aged 50 or older. * Be able (or have their Legally Authorized Representative (LAR) be able) to understand the study and be willing to sign a written informed consent document. * Have been diagnosed by a neurologist or psych…
Interventions
- Drug18F-PF974
Injected IV followed by PET scanning
- Drug18F-florbetaben
Injected IV followed by PET scanning
Location
- National Institutes of Health Clinical CenterBethesda, Maryland