CBDEarly Phase 1NCT04398719
CBD-Microglia PET Study
A Early Phase 1 study testing [11C]PBR28, Low-dose lipopolysaccharide and Intradermal Capsaicin in people with CBD and Healthy, run by Yale University at 1 site in United States.
Trial summary
This study aims to examine the effect of cannabidiol (CBD) pre-treatment on brain microglial activation in healthy human subjects. Secondarily, this study aims to examine the effect of cannabidiol (CBD) pre-treatment on central pain-sensitization in healthy human subjects. Read more about this study
- Who is it for?
- Ages 18 to 55 yearsHealthy volunteers can take part
- What is being tested?
- [11C]PBR28, Low-dose lipopolysaccharide and Intradermal Capsaicin
- Type of treatment
- Injection or infusion, Surgery or procedure
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 28 participants
- Where
- 1 siteUnited States
- Study dates
- 7 May 2021to 11 Dec 2024
- Phase
- Early Phase 1
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 55 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Men and women aged 18- 55 years
- No significant medical or neurological illness
- No implanted metal devices that may pose a risk during MRI scanning
- Within the annual permissible radiation exposure
- Able to provide written informed consent.
Who cannot join
- Current use of any medications
- Presence of metal in the body
- Pregnancy or lactation
Trial locations and contacts
1 site in 1 country.
United States1 site
Connecticut Mental Health Center
New Haven, Connecticut, 06519
About this study
Official title: Effect of Cannabidiol on Microglial Activation and Central Pain-Sensitization
This study aims to examine the effect of cannabidiol (CBD) pre-treatment on brain microglial activation in healthy human subjects. Secondarily, this study aims to examine the effect of cannabidiol (CBD) pre-treatment on central pain-sensitization in healthy human subjects.
Read the detailed description
This study aims to examine the effect of cannabidiol (CBD), pre-treatment, as Epidiolex, on brain microglial activation in healthy human subjects using [11C]PBR28 PET imaging. Secondarily, this study aims to examine the effect of cannabidiol (CBD) pre-treatment on central pain-sensitization in healthy human subjects. Lastly, this research study will also examine the relationship between brain microglial activation and central pain sensitization with CBD pre-treatment.
- Being tested
- [11C]PBR28, Low-dose lipopolysaccharide, Intradermal Capsaicin
- Keywords
- Control, PET Scan, MRI Scan, Central Pain-Sensitization, Cannabidiol
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
[11C]PBR28Radiation
Also called PET scan
The radiotracer, [11C]PBR28, will be administered at the beginning of each PET scan
Low-dose lipopolysaccharideDrug
Also called LPS
Subjects will receive intravenous lipopolysaccharide.
Intradermal CapsaicinDrug
A small dose of capsaicin will be administered by intradermal injection.
| Study group | Role | What they receive |
|---|---|---|
| CBD | Active comparator | Not described Receives: Radiation: [11C]PBR28; Drug: Low-dose lipopolysaccharide; Drug: Intradermal Capsaicin |
| Placebo | Placebo comparator | Not described Receives: Radiation: [11C]PBR28; Drug: Low-dose lipopolysaccharide; Drug: Intradermal Capsaicin |
What is being measured
The primary outcome is the main question the study is designed to answer.
Microglial activation using [11C]PBR28 PET imaging
Difference in microglial activation ([11C]PBR28 VT levels) between the 2 groups (e.g., CBD vs. placebo)
Measured: 10 Days
Secondary outcomes (1)
Capsaicin-induced hyperalgesia
Difference in capsaicin-induced hyperalgesia between the 2 groups (e.g., CBD vs. placebo)
Measured: 10 Days
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted21 May 2020
- Study start7 May 2021
- Primary completion11 Dec 2024
- Study completion11 Dec 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for CBDStudies of the same condition, open and under way.
- More trials run by Yale UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Early Phase 1
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind
- Who is masked
- Participant, Investigator, Outcomes assessor
- Enrolment
- 28 participants (actual)
Sponsor and investigators
- Lead sponsor
- Yale University
- Sponsor type
- University, hospital or other
- Collaborators
- National Center for Complementary and Integrative Health (NCCIH)
- Responsible party
- Principal investigator, Mohini Ranganathan, Yale University
- Investigators
- Mohini Ranganathan, MD, Principal investigator, Yale University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04398719
- Sponsor's protocol ID
- 2000026320
- Status last verified
- Apr 2026
- First submitted
- 19 May 2020
- Last updated
- 29 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 29 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effect of Cannabidiol on Microglial Activation and Central Pain-Sensitization
- ClinicalTrials.gov ID
- NCT04398719
- Acronym / sponsor ID
- 2000026320
- Keywords
- Control, PET Scan, MRI Scan, Central Pain-Sensitization, Cannabidiol
- Phase
- Early Phase 1
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 28 participants (actual)
- Lead sponsor
- Yale UniversityUniversity, hospital or other
- Collaborators
- National Center for Complementary and Integrative Health (NCCIH)
- Study start
- 7 May 2021 (actual)
- Primary completion
- 11 Dec 2024 (actual)
- Study completion
- 11 Dec 2024 (actual)
- First posted
- 21 May 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study aims to examine the effect of cannabidiol (CBD) pre-treatment on brain microglial activation in healthy human subjects. Secondarily, this study aims to examine the effect of cannabidiol (CBD) pre-treatment on central pain-sensitization in healthy human subjects.
Detailed description
This study aims to examine the effect of cannabidiol (CBD), pre-treatment, as Epidiolex, on brain microglial activation in healthy human subjects using [11C]PBR28 PET imaging. Secondarily, this study aims to examine the effect of cannabidiol (CBD) pre-treatment on central pain-sensitization in healthy human subjects. Lastly, this research study will also examine the relationship between brain microglial activation and central pain sensitization with CBD pre-treatment.
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind (participant, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| CBD | Active comparator | Radiation: [11C]PBR28, Drug: Low-dose lipopolysaccharide, Drug: Intradermal Capsaicin |
| Placebo | Placebo comparator | Radiation: [11C]PBR28, Drug: Low-dose lipopolysaccharide, Drug: Intradermal Capsaicin |
Who may qualify
- Ages
- 18 to 55 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Men and women aged 18- 55 years
- No significant medical or neurological illness
- No implanted metal devices that may pose a risk during MRI scanning
- Within the annual permissible radiation exposure
- Able to provide written informed consent.
Key exclusion criteria (3 listed)
- Current use of any medications
- Presence of metal in the body
- Pregnancy or lactation
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| [11C]PBR28Also: PET scanThe radiotracer, [11C]PBR28, will be administered at the beginning of each PET scan | Radiation | CBD, Placebo |
| Low-dose lipopolysaccharideAlso: LPSSubjects will receive intravenous lipopolysaccharide. | Drug | CBD, Placebo |
| Intradermal CapsaicinA small dose of capsaicin will be administered by intradermal injection. | Drug | CBD, Placebo |
Primary outcome
Microglial activation using [11C]PBR28 PET imaging
Time frame: 10 Days
Difference in microglial activation ([11C]PBR28 VT levels) between the 2 groups (e.g., CBD vs. placebo)
1 secondary outcome
Capsaicin-induced hyperalgesia
Time frame: 10 Days
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Apr 2026.
Related trials for CBD
Not yet recruiting
CannaRiver CBD Calm for Anxiety, Sleep, and Well-Being in Adults With Generalized Anxiety Disorder
Generalized Anxiety Disorder
RecruitingPhase 1
A Study to Evaluate the Efficacy and Safety of Cannabidiol Oral Solution (CBD-OS [GWP42003-P, JZP926]) for the Treatment of Focal-Onset Seizures
Focal Seizures
RecruitingEarly Phase 1
Neuroprotective Potential of Cannabidiol (CBD) in Preventing Oxaliplatin (Ox)-Induced Neuropathy
Oxaliplatin Induced Peripheral Neuropathy in Cancer Patients, Metastatic Colorectal Cancer (CRC)
Not yet recruitingPhase 4
A Study to Investigate the Effect of Gradual Titration to Optimize Cannabidiol Treatment in Adults With LGS
Lennox-Gastaut Syndrome
RecruitingEarly Phase 1
Cannabidiol in Opioid Use Disorder and Chronic Pain With Buprenorphine
Chronic Pain, Opioid Use Disorder
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Mohini Ranganathan, MD principal investigator
Yale University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Early Phase 1 study testing [11C]PBR28, Low-dose lipopolysaccharide and Intradermal Capsaicin in people with CBD and Healthy, run by Yale University at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 29 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Early Phase 1 (sometimes called Phase 0) studies give a very small amount of a treatment to a few people, mainly to see how the body handles it.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Microglial activation using [11C]PBR28 PET imaging (time frame: 10 Days). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Apr 2026.