Varenicline as a Treatment for Cannabis Use Disorder

NCT07783555 | Not Yet Recruiting Phase 2 DMC FDA Drug

• 1 other identifier: Pro00150924
• Study Type: interventional
• Target: 224
• Locations: 0 countries
• Sites: N/A

Brief Summary

Marijuana is the most commonly used illicit drug, and there is a high demand for effective treatments for cannabis use disorder, yet few specific pharmacological treatments have been developed. This study will evaluate the efficacy and safety of varenicline for reducing marijuana use in adults who use marijuana frequently. Participants will be randomized to receive either varenicline or placebo for 12 weeks, along with computerized cognitive behavioral therapy. Cannabis use, medication adherence, and safety outcomes will be assessed throughout treatment and at a follow-up visit.

Conditions

Cannabis Abuse

Outcome Measures

Primary Outcomes (3)

• Cannabis use reduction

  The primary efficacy outcome is cannabis use reduction as measured by daily substance use logs and examined as the total number of use sessions at each weekly visit.

  Weeks 6-12

• Group equivalence

  There will equivalence of the average number of weekly use sessions reported between men and women.

  Weeks 6-12

• Treatment responder classification

  Determine what baseline demographic, cannabis use, and clinical characteristics best differentiate positive study treatment responders as compared to non-responders .

  Weeks 6-12

Study Arms (2)

Varenicline

ACTIVE COMPARATOR

Varenicline will be provided at the standard recommended dose of 0.5mg daily for three days, then 0.5mg twice daily for four days, and then 1mg twice daily for the remainder of the 12-week treatment period.

Drug: Varenicline (Chantix)

Placebo

PLACEBO COMPARATOR

Matched placebo administered daily for 12 weeks.

Drug: Placebo

Interventions

Varenicline (Chantix) DRUG

Varenicline will be provided at the standard recommended dose of 0.5mg daily for three days, then 0.5mg twice daily for four days, and then 1mg twice daily for the remainder of the 12-week treatment period.

Varenicline

Placebo DRUG

Matched placebo administered daily for 12 weeks.

Placebo

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age ≥ 18 years
• DSM-5 diagnosis of cannabis use disorder
• Cannabis use ≥ 3 days per week in past 30 days
• Ability to read English and provide informed consent
• Willingness to comply with medication and study procedures
• Agreement to use acceptable contraception if of childbearing potential

You may not qualify if:

• Pregnant, breastfeeding, or planning pregnancy
• Severe renal impairment (CrCl \< 30 mL/min)
• Lifetime bipolar I or II disorder, schizophrenia, or other psychotic disorder
• Suicidal ideation or behavior within 6 months
• Use of excluded psychotropic medications (e.g., bupropion, nortriptyline)
• Moderate or severe non-cannabis substance use disorder (except nicotine)
• Clinically significant cardiovascular or cerebrovascular disease in past 6 months
• Hypersensitivity to varenicline
• Participation in another investigational drug study within 30 days

Sponsors & Collaborators

• Medical University of South Carolina: lead
• National Institute on Drug Abuse (NIDA): collaborator
• National Institutes of Health (NIH): collaborator

MeSH Terms

Conditions

Marijuana Abuse

Interventions

Varenicline

Condition Hierarchy (Ancestors)

Substance-Related Disorders; Chemically-Induced Disorders; Mental Disorders

Intervention Hierarchy (Ancestors)

Benzazepines; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Heterocyclic Compounds; Quinoxalines

Central Study Contacts

Lisa Program Manager, MS

CONTACT

843-792-0476; jenkinli@musc.edu

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor-Faculty

Study Record Dates

• First Submitted: August 20, 2026
• First Posted: August 25, 2026
• Study Start (Estimated): December 1, 2026
• Primary Completion (Estimated): November 30, 2031
• Study Completion (Estimated): November 30, 2031
• Last Updated: August 25, 2026

Record last verified: 2026-08

Data Sharing

• IPD Sharing: Will not share