Clinical Trials Logo

Clinical Trial Summary

Tobacco and cannabis co-use is a common and growing public health problem, especially in states that have legalized cannabis. There are no pharmacologic treatments for co-occurring tobacco and cannabis use. Co-use may make quitting either substance more difficult, given the synergistic effects of cannabis and nicotine on neurobiological systems that mediate reward and shared cues reinforcing co-use. N-acetylcysteine (NAC), an FDA-approved medication and over-the-counter supplement, has shown promise in animal studies and randomized controlled trials (RCTs) in reducing tobacco and cannabis craving and use.


Clinical Trial Description

N-acetylcysteine (NAC), an FDA-approved medication and over-the-counter supplement, has shown promise in animal studies and randomized controlled trials (RCTs) in reducing tobacco and cannabis craving and use. NAC's efficacy in treating addiction may be attributable to its central nervous system effects in reducing excessive glutamatergic activity, oxidative stress, and inflammation. NAC has been shown to improve cognition and reduce impulsivity, which in turn may strengthen inhibitory control when presented with contextual cues. To date, no RCT has examined NAC for smoking cessation in the setting of tobacco-cannabis co-use. In a double-blind, placebo-controlled RCT, the investigators will examine a novel pharmacological treatment, NAC, for concurrent tobacco use disorder (TUD) and cannabis use in dual users of tobacco and cannabis. Sixty adult regular cigarette smokers who 1) have smoked 2 cigarettes per day in 15 of the past 30 days, or an average of 1 cigarettes per day for the past 30 days and 2) use cannabis regularly and 3) consent to receive interventions to stop smoking cigarettes and using cannabis will be randomized to receive NAC 3600 mg per day or placebo over 8 weeks. Participants in both groups will receive 8 weekly cognitive behavioral therapy sessions addressing both tobacco and cannabis use. Outcomes will be assessed at Weeks 0, 4, 8, and 12. Primary aims are to determine NAC's efficacy in decreasing cigarette use, nicotine dependence levels, and craving; and cannabis use, and craving. Exploratory aims include examination of changes in neurocognition with NAC and their potential mediational effects on cigarette and cannabis use outcomes. NAC SUB-STUDY: Because of the significant clinical and economic burden imposed by tobacco and cannabis use, it is important to understand the mechanism underlying the progression of tobacco (TUD) and cannabis use disorders (CUD) and any potential treatments. TUD and CUD are associated with elevated oxidative stress and chronic inflammation. It has been suggested that patients dependent on these substances have dysregulated markers of oxidation and inflammation, including gluthathione, erythrocyte sedimentation rate (ESR), C-Reactive protein (CRP), Interleukin-6 (IL-6). In this sub-study, baseline levels of commonly utilized serum markers of oxidation status and inflammation will be measured in 20 adults recruited under the main study, with the option of being a part of the sub-study who also demonstrate concurrent TUD and cannabis use. The correlation will be determined between changes in serum markers of oxidative stress and magnitude of use of cigarettes and cannabis. If successful, the investigator will establish regulatory patterns of oxidative stress and inflammation in TUD and with concurrent cannabis use for the first time, and will implicate oxidative stress and inflammation as playing key roles in the progression and severity of co-occurring TUD and CUD. ;


Study Design


Related Conditions & MeSH terms


NCT number NCT04627922
Study type Interventional
Source University of California, San Francisco
Contact Madeline Martinez Rivas, PhD
Phone 415-530-7255
Email Madeline.Martinezrivas@va.gov
Status Recruiting
Phase Phase 4
Start date August 25, 2021
Completion date August 25, 2024

See also
  Status Clinical Trial Phase
Withdrawn NCT02432066 - Effects of GTS-21 on Smoking Behavior and Neurocognitive Functions Phase 2
Completed NCT03960138 - Examining the Effects of Neural Stimulation on Inhibitory Control and Cigarette Smoking N/A
Recruiting NCT05030272 - Comparing Two Behavioral Approaches to Quitting Smoking in Mental Health Settings N/A
Completed NCT04646668 - Comparative Abuse Liability Among African American and White Smokers N/A
Completed NCT02560324 - Effect of Ramelteon on Smoking Abstinence Phase 2
Completed NCT02347605 - Medicinal Nicotine for Preventing Cue Induced Craving N/A
Completed NCT01428310 - Study to Evaluate the Safety and Efficacy of Dietary Supplement Anatabloc in Reducing Daily Smokers' Urge to Smoke Phase 1
Terminated NCT01800500 - Interest in Smokeless Tobacco Product as a Substitution for Cigarettes in Current Smokers N/A
Completed NCT01442753 - Family-Skills Training to Prevent Tobacco and Other Substance Use in Latino Youth N/A
Completed NCT01570595 - Positively Smoke Free on the Web (PSFW) for Smokers Living With HIV Phase 1/Phase 2
Completed NCT01625767 - Tobacco Approach Avoidance Training for Adolescent Smokers-1 Phase 2
Active, not recruiting NCT01539525 - Screening to Augment Referral to Treatment- Project START Phase 2
Completed NCT00967005 - N-Acetyl Cysteine Plus Behavioral Therapy for Nicotine Dependent Pathological Gamblers Phase 2
Completed NCT01337817 - A Pilot Study to Evaluate the Efficacy and Safety of Ariva® Silver Wintergreen in Healthy Smokers Phase 1
Active, not recruiting NCT00751660 - Screening Methods in Finding Lung Cancer Early in Current or Former Smokers N/A
Completed NCT00790569 - Varenicline or Nicotine Patch and Nicotine Gum in Helping Smokers in a Methadone Treatment Program Stop Smoking N/A
Completed NCT00664261 - Clinical Effort Against Secondhand Smoke (CEASE) Program or Standard Care in Helping Parents Stop Smoking N/A
Completed NCT00158158 - Effectiveness of Reducing Smoking in Facilitating Smoking Cessation in Adolescents - 2 Phase 2/Phase 3
Completed NCT00134927 - A Survey on Consumer Use of Over-the-Counter (OTC) Nicotine Patches N/A
Completed NCT00218179 - Assessing the Link Between Smoke Carcinogen Biomarkers and Lung Cancer Risk - 1 N/A