NCT05582200 · The Methodist Hospital Research Institute
Selective PET Imaging of Astrocytes and Microglia in Alzheimer's Disease
What this study is about
Inflammation occurs in many brain diseases including Alzheimer's disease. In Alzheimer's disease, an abnormal protein called amyloid starts accumulating decades before the start of forgetfulness.
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Inflammation occurs in many brain diseases including Alzheimer's disease. In Alzheimer's disease, an abnormal protein called amyloid starts accumulating decades before the start of forgetfulness. However, scientists have reported that inflammation but not amyloid is linked to forgetfulness and the topography of brain inflammation and tau buildup are closely correlated in patients with mild cognitive impairment due to Alzheimer's disease. New medications are under development to help healing and prevent permanent damage in the brain. To see if inflammation is improving or getting worse with these medications, investigators can watch inside of the brain using a special camera called positron emission tomography (PET). It is currently possible to watch inflammation in the brain by taking pictures of a molecule called translocator protein (TSPO). But the problem is that by imaging TSPO, investigators can catch changes in more than one kind of cells. The information is not specific to each cell type. Such vague information is not completely useful to monitor the effect of new medications for inflammation. This proposal attempts to develop a novel method to capture changes in each of two major players in inflammation, microglia and astrocytes. To do so, investigators will take selective pictures of one cell type by using a novel imaging agent for PET. Investigators will also take PET pictures of TSPO. Investigators will process these two kinds of PET pictures using advanced mathematical methods and extract specific information on microglia and astrocytes. Our novel method will be useful to monitor new therapies to treat inflammation in the brain.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Individuals of either sex, 50-90 years of age.
- Meeting research criteria for AD (McKhann, Knopman et al. 2011).
- With a CDR (Morris 1993) score of 1-3.
- Fluent in English or Spanish.
- Have sufficient communication and comprehension ability to consent to the performance of the study or have a legally authorized representative.
Exclusion criteria
- Inability to undergo MRI or PET for any reason, including severe claustrophobia.
- History of large stroke or brain trauma, multiple sclerosis or other brain disorder that, in the judgment of the PI may confound the study.
- Pregnancy. In women in whom the possibility of pregnancy cannot be excluded, a pregnancy test must be performed on site the morning of any PET visit and a negative result together with a physician interview are required prior to the administration or any radiopharmaceutical.
- Research radiation exposure greater than 50 mSv effective dose within 12 months including radiation exposure from this study. Healthy volunteers: Inclusion criteria:
- Individuals of 18-90 years of age.
- Negative amyloid accumulation determined by PET (only for the comparison with AD).
- Fluent in English.
- Have enough communication and comprehension ability to consent to the performance of the study. Exclusion criteria:
- Inability to undergo MRI or PET for any reason, including severe claustrophobia.
- Brain disorder, other than idiopathic headache.
- Current primary Axis I or II psychiatric disorder.
- Current use of psychotropic or anti-epileptic medication.
- Substance abuse during the past two years.
- Active cancer, metabolic encephalopathy, infection, cardiovascular disease.
- Active hematological, renal, pulmonary, endocrine or hepatic disorders, except for treated thyroid disease.
- Pregnancy. In women in whom the possibility of pregnancy cannot be excluded, a pregnancy test must be performed on site the morning of any PET visit and a negative result together with a physician interview are required prior to the administration or any radiopharmaceutical
- Research radiation exposure greater than 50 mSv effective dose within 12 months including radiation exposure from this study.
- Only for the subjects undergoing the blocked scan with selegiline: known contraindications to selegiline, including hypersensitivity to the drug and use of opioids, such as meperidine and some antidepressants such as bupropion.
Where
- Houston, Texas
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Apr 6, 2026 · Source of record for eligibility and locations