Background:
Glucagon-like peptide 1 (GLP-1) agonist drugs are used to treat diabetes and aid weight loss. They may also help reduce cravings for drugs and alcohol. Researchers want to know if a GLP-1 drug (tirzepatide) can lessen the urge to drink in people with alcohol use disorder (AUD).
Objective:
To learn how the brains of people with AUD respond to a GLP-1 drug.
Eligibility:
People aged 21 to 65 years with AUD who are non-treatment seeking. They must be enrolled in protocol 14-AA-0181. Healthy volunteers are also needed.
Design:
This study consists of Part 1 and Part 2.
Part 1 (Imaging Procedures): Five healthy volunteers will undergo 2 to 3 combined positron emission tomography/magnetic resonance imaging (PET/MRI) scans, with an interval of 2 to 3 weeks between scans. For each scan, a radioactive substance (tracer) will be administered intravenously. Participants will undergo PET/MRI scanning to assess brain activity during resting state. Methylphenidate (Ritalin) will be administered during each scan. Each imaging session will last approximately 2 hours. Tirzepatide and placebo will not be administered in Part 1. Participants with alcohol use disorder (AUD) are not included in Part 1. The purpose of this part of the study is to assess test/retest reproducibility of the PET/MRI combined scan measures.
Part 2 (Randomization to Tirzepatide \& Placebo): Participants will be randomized to receive either Tirzepatide or Placebo first. Healthy Volunteers and AUD participants will receive both treatments in a crossover design. Tirzepatide and placebo will be administered via subcutaneous injection (under the skin) once weekly for 2 to 3 weeks. This treatment period will be followed by 2 to 3 PET/MRI combined imaging scans described in the next paragraph. After a washout interval of approximately 2 to 3 weeks, participants will cross over to the alternate treatment (tirzepatide or placebo), administered once weekly for 2 to 3 weeks. This second treatment period will be followed by an additional 2 to 3 PET/MRI scans. Participants may receive up to 3 doses of tirzepatide and 3 doses of placebo.
Part 2 (Imaging Procedures): Healthy Volunteers and participants with an AUD will undergo PET/MRI scans at two time points: following tirzepatide administration and following placebo administration. For each scan a radioactive substance (tracer) will be administered intravenously. Brain activity will be measured during PET/MRI acquisition during resting state. Methylphenidate will be administered during 1 of the scans at each time point. Each imaging session will last approximately 2 hours. Participants will wear a device to track their activity for at least 1 week before each set of scans. They will have tests of their thinking, memory, and attention.
Enrollment in 14AA0181.
Stated willingness to comply with all study procedures and availability for the duration of the study.
Male or female, ages 21-65 years old.
Ability to understand and willingness to sign a written informed consent document.
Presence of ferromagnetic objects in the body that are contraindicated for MRI of the head, fear of enclosed spaces, or other standard contraindication to MRI
Cannot lie comfortably flat on his/her back for up to 2 hours in the PET/MRI scanner.
BMI <23 or >35 (but no more than 500 lbs). The PET/MRI scanner bed is tested to a weight limit of 500 lbs.
Have had previous radiation exposure (from X-rays, PET scans, or other exposure) that, with the exposure from this study, would exceed NIH annual research limits as determined by medical history and physical exam.