A Phase 2 interventional study of Tirzepatide and Placebo in Cannabis Use Disorder, sponsored by National Institute on Drug Abuse (NIDA). Not yet recruiting. Open to participants aged 18 Years to 70 Years. Per ClinicalTrials.gov, last updated 2026-09-21.
Sponsored by National Institute on Drug Abuse (NIDA) · Phase 2, Interventional, and Treatment
The purpose of this randomized, double-blind, placebo-controlled, multi-site clinical trial is to evaluate the safety and efficacy of tirzepatide in a sample of 100 patients diagnosed with moderate or severe CUD by DSM-5 criteria.
This is a double-blind, placebo-controlled, randomized clinical trial. 100 individuals with moderate to severe cannabis use disorder (CUD) will be randomized in a 1:1 ratio to receive either (1) weekly subcutaneous injections of tirzepatide or (2) weekly subcutaneous injections of matching placebo for 24 weeks. Tirzepatide will be initiated at 2.5 mg for 4 weeks (4 injections) and increased in 2.5 mg increments every 4 weeks as tolerated, up to a maximum dose of 15 mg.
The Primary Objective is to determine the maximum tolerated dose (MTD) of tirzepatide in individuals with CUD and to evaluate its efficacy in reducing cannabis use.
The primary Hypothesis is that tirzepatide will be well tolerated within the FDA-recommended dose range and compared with placebo, it will result in a significantly greater proportion of cannabis abstinent days as measured by the timeline follow-back (TLFB).
Secondary Objectives are to evaluate the effects of tirzepatide, relative to placebo, on (1) CUD severity based on DSM-5 criteria; (2) percentage of cannabis-negative weekly urine drug screens collected during the treatment period; (3) cannabis craving; (4) cannabis withdrawal severity; (5) retention in treatment; and (6) quality of life.
188 studies on the registry are indexed under Marijuana Abuse; 26 are open to participants now.
This study's planned enrollment of 100 is above the median of 51 across 160 interventional studies indexed under Marijuana Abuse.
Browse Marijuana Abuse studies →National Institute on Drug Abuse (NIDA) is the lead sponsor of 393 studies on the registry; 19 are open to participants now.
Of its 14 completed or terminated interventional studies of FDA-regulated products, 6 (43%) have results posted.
Compared within Marijuana Abuse, the registry's first condition term, which may not be this study's main condition. Counted across the registry records on this site, refreshed daily. How we classify →
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
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.
The American Psychiatric Association’s manual of mental health diagnoses. DSM-5 (2013, revised as DSM-5-TR in 2022) replaced DSM-IV, and some studies still name the older edition. “Meets DSM criteria for …” means diagnosed by that edition’s diagnostic criteria, usually by a clinician in an interview.
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.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
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.
DSM diagnostic criteria
The American Psychiatric Association’s manual of mental health diagnoses. DSM-5 (2013, revised as DSM-5-TR in 2022) replaced DSM-IV, and some studies still name the older edition. “Meets DSM criteria for …” means diagnosed by that edition’s diagnostic criteria, usually by a clinician in an interview.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
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.
Drug: Tirzepatide
Drug: Placebo
Participants will receive weekly injections of tirzepatide 2.5 mg for 4 weeks. The dose is expected to increase by 2.5 mg every 4 weeks, however, the decision to increase the dose will be made based on the Dose Increase Checklist and shared decision between the site study physician (MD or DO) and the participant.
Participants will receive weekly masked injections of placebo.
Maximum Tolerated Dose (MTD)
The maximum tolerated dose defined as the median dose within the FDA-recommended range, at which dose increase is not recommended (based on standardized and health care provider assessments).
Time frame: 24 weeks (Treatment Phase)
Days of Abstinence
Number of days per week with no cannabis use, as assessed by Timeline Follow Back (TLFB).
Time frame: 24 weeks (Treatment Phase)
Severity of Cannabis Use Disorder (CUD)
Severity of CUD as determined by DSM-5 criteria for Cannabis Use Disorder Checklist and expressed as a number of reported symptoms
Time frame: 24 weeks (Treatment Phase)
Negative Urine Drug Screens (UDS)
Percentage of weekly urine drug screens testing negative for cannabis out of all scheduled weekly drug screens.
Time frame: 24 weeks (Treatment Phase)
Cannabis Craving
Cannabis Craving as assessed by the short form of the Marijuana Craving Questionnaire (MCQ) and expressed as a score. The score range is 12-84, and the higher score indicates a higher or more frequent level of craving.
Time frame: 24 weeks (Treatment Phase)
1. Cannabis Withdrawal
Cannabis withdrawal as assessed by the DSM 5 Cannabis Withdrawal Checklist and expressed as a number of symptoms present (up to 7)
Time frame: 24 weeks (Treatment Phase)
Retention in Treatment
Percentage of randomized participants who receive study medication during the treatment phase.
Time frame: Week 24 (End of Treatment Phase)
Quality of Life
Quality of life (physical function, anxiety, depression, fatigue, sleep disturbance, ability to participate in social roles and activities, and pain intensity) as determined by PROMIS-29 questionnaire and expressed as a score. The domain scores (T-scores) range is 20-80 with higher scores representing better outcomes.
Time frame: 24 weeks (Treatment Phase)
No study locations are listed for this record.
Plan to share: Undecided
No publications or documents are linked to this record.
This study is not yet recruiting, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Tirzepatide
National Institute on Drug Abuse (NIDA) →