An observational study in Alzheimer Disease, sponsored by Tammie L. S. Benzinger, MD, PhD. Active, not recruiting at 1 site in United States. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-08-24.
Sponsored by Tammie L. S. Benzinger, MD, PhD · Observational
There is a compelling need for a noninvasive imaging approach to measure S1P1 in both preclinical models of diseases and humans. PET measures of S1P1 expression is critical for elucidating the pathophysiological roles of S1P1 in neuroinflammation and neurodegeneration. The relevance of S1P1 in clinical disease has become readily apparent with the FDA approval of the S1P1 modulator FTY720 (fingolimod) for treating relapsing-remitting MS (RR-MS). MS is a chronic autoimmune, inflammatory disease caused by lymphocytic infiltration that leads to demyelinating neurodegenerative disease.
The primary objective of the initial IND study is to determine the safety of the [11C]-CS1P1 for PET imaging of S1P1 expression. The investigators will first complete whole-body PET dosimetry studies in healthy adult normal volunteers to calculate the actual radiation dose of each human organ and determine the allowable dose for a human subject when receiving a single dose for a PET scan. Second, complete imaging of the brain and lymph nodes of the neck in a wide range of ages of healthy adult normal control participants, both male and females to characterize [11C]-CS1P1 uptake in the brain and radiolabeled metabolite will be completed. Finally, a comparison of the normal control participants to patients with multiple sclerosis (MS) will be completed.
3,965 studies on the registry are indexed under Alzheimer Disease; 926 are open to participants now.
This study's planned enrollment of 60 is below the median of 200 across 814 observational studies indexed under Alzheimer Disease.
Browse Alzheimer Disease studies →Tammie L. S. Benzinger, MD, PhD is the lead sponsor of 11 studies on the registry; 4 are open to participants now.
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Aim 1: Dosimetry/ Safety Group Ten healthy adult volunteers (5 males and 5 females) will be recruited and undergo whole-body PET/CT imaging for assessing the safety, dosimetry and metabolism of [11C]-CS1P1.
Aim 2: Feasibility Cohort Aim 2A will consist of 24 adult volunteers that will be recruited and scanned to characterize [11C] CS1P1 uptake on PET scans of the brain and cervical lymph nodes, to assess for radiolabeled metabolites. Up to 20 participants who have completed Aim 2A will continue with the collection of test-retest and safety data, Aim 2B. Ten healthy controls age and gender-matched to 10 participants with MS will be invited to return for repeat imaging for test-retest reliability not less than 7 days after and not more than 12 months after baseline imaging.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
A “mini-stroke”: temporary stroke-like symptoms caused by reduced blood flow to part of the brain, spinal cord or eye, without signs of a new stroke on a scan.
Stroke symptoms need emergency care at once, even if they go away.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
TIA (transient ischaemic attack)
A “mini-stroke”: temporary stroke-like symptoms caused by reduced blood flow to part of the brain, spinal cord or eye, without signs of a new stroke on a scan.
Stroke symptoms need emergency care at once, even if they go away.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Drug: [11C]-CS1P1
Participants will receive a single intravenous bolus injection of 6.0 - 20.0 mCi (222-740 MBq) of the investigational radiotracer \[11C\] CS1P1. Participants will then undergo a \[11C\] CS1P1 PET/CT scan.
The tracer [11C]-CS1P1 will be injected for the first time into humans, using a dose range of 12-17 mCi for evaluations of safety, biodistribution, and dosimetry.
Whole-body PET/CT images (skull vertex to proximal thighs) will be obtained in 10 healthy volunteers (5 males and 5 females) for up to a maximum of 4 hours immediately following intravenous (IV) injection of 12-17 mCi of \[11C\]-CS1P1 (dosage range calculated from rodent dosimetry data extrapolated to humans).
Time frame: 2 years
PET imaging studies of [11C]-CS1P1 in healthy normal control participants and human participants with multiple sclerosis.
We hypothesize that specific binding of \[11C\]-CS1P1 is elevated in participants with neuroinflammatory/neurodegenerative diseases of the CNS compared to healthy normal control participants.
Time frame: 2 years
This study is active, not recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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Tammie L. S. Benzinger, MD, PhD