NCT07800520 · Yale University
Characterization of CB1 Receptors Using [11-C]OMAR in Opioid Use Disorder
What this study is about
The goals of this sub-study is to assess CB1R availability in early abstinent individuals with OUD (following opioid agonist therapy - OAT stabilization) and in matched healthy controls.
View original scientific description
The goals of this sub-study is to assess CB1R availability in early abstinent individuals with OUD (following opioid agonist therapy - OAT stabilization) and in matched healthy controls.
Interventions
DRUG
[11C]OMAR
For each \[11C\]OMAR PET scan, up to 20 mCi of \[11C\]OMAR will be administered.
Primary outcome measures
CB1R Availability
Time frame: Day 7
To compare cortical CB1R availability (volume of distribution, mL/cm3) assessed using brain PET imaging in individuals diagnosed with opioid use disorder on chronic methadone maintenance vs. matched healthy controls.
Mean Beck Depression Inventory (BDI) score
Time frame: Days 7, 28, 49, 70, 90
A 21-question self-report tool to assess depression symptoms. Total score range 0 to 63, higher scores indicating more severe symptoms.
Mean Anxiety Inventory (BAI) score
Time frame: Days 7, 28, 49, 70, 90
A 21-question self-report tool to assess anxiety symptoms. Total score range 0 to 63, higher scores indicating more severe anxiety.
Mean Perceived Stress Scale (PSS) score
Time frame: Days 7, 28, 49, 70, 90
The PSS is a 10-item self- report scale. PSS scores are obtained by reversing responses to the four positively stated items (items 4, 5, 7, \& 8) and then summing across all scale items. Total score range from 0-40 with higher scores indicate greater levels of stress.
Mean Opioid Relapse days
Time frame: Days 7, 14, 21, 28, 35, 42, 49, 56, 70, 77, 84, 90
Mean Opioid Relapse days assessed using Timeline Follow Back (TLFB)
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
- Normal screening bloodwork.
- Adequate arterial access for placement of an arterial line and blood sampling per study protocol. OUD Participants:
- Diagnosis of opioid use disorder (OUD) according to DSM-5 criteria.
- Actively seeking treatment for OUD.
- Willingness to initiate opioid agonist therapy (OAT) with buprenorphine. Healthy Controls:
- Good general physical health.
- No current or past diagnosis of any psychiatric or substance use disorders.
Exclusion criteria
- Any current major medical condition that, in the opinion of the Principal Investigator, poses a risk for PET procedures.
- Prior participation in research studies within the past year that would result in cumulative radiation exposure exceeding annual limits.
- Presence of ferromagnetic metal in the body, pacemaker, or other contraindications to MRI.
- Positive pregnancy test or current lactation.
- History of neurological conditions, including stroke or seizure disorders.
- Hematocrit values lower than 30 OUD Participants
- Current or past diagnosis of a serious psychiatric disorder.
- Current diagnosis of any substance use disorder other than nicotine or opioids.
- Use of any substances within the past 30 days.
- Current use of SSRIs or benzodiazepines or use within the past 30 days.
- Previous enrollment in the main study. Healthy Controls:
- Current or past diagnosis of any psychiatric disorder.
- Current diagnosis of any substance use disorder (excluding nicotine).
- Use of any substances within the past 30 days.
Where
- New Haven, Connecticut
Collaborators
National Institute on Drug Abuse (NIDA)
Related conditions & keywords
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 Oct 2, 2026 · Source of record for eligibility and locations