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Tundra lists 28 Cigarette Smoking clinical trials. Each listing includes eligibility criteria, study locations, and direct links to research sites in the Tundra directory.
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NCT06966362
Varenicline for Smoking Reduction in Veterans Not Ready To Quit
In order to reduce the prevalence of cigarette smoking among Veterans, it is vital that healthcare providers offer effective tobacco treatment to all Veterans who smoke, including those not ready to make a quit attempt. Smoking treatments currently available to Veterans who are not ready to quit are only weakly effective. This project will generate new knowledge about the effectiveness of a promising varenicline-based intervention designed to increase quit attempts and long-term abstinence in Veterans who are initially not ready to quit. This project has great potential to engage Veterans not ready to quit smoking in treatment that increases quit attempts and quitting success, thereby reducing morbidity and mortality caused by smoking in Veterans.
Gender: All
Ages: 21 Years - Any
Updated: 2026-03-13
4 states
NCT06372899
Noncombustible Nicotine Delivery Systems as Potential Harm Reduction Tools for Persistent Cigarette Smokers
This between-subjects study aims to evaluate whether e-cigarettes (ECIGS) versus oral nicotine pouches (ONPS) more readily substitute for combustible cigarettes among 200 cigarette smokers. After measuring baseline cigarette smoking rate, participants will be randomized to ECIGS or ONPS and be instructed to switch (versus smoking cigarettes) over a 6-week period. Relative reductions in biomarkers of exposure will be measured. ECIG- and ONP-associated subjective reward and the reinforcing value of ECIGS and ONPS relative to combustible cigarettes will be assessed as mechanisms.
Gender: All
Ages: 21 Years - Any
Updated: 2026-03-12
1 state
NCT05722561
E-Cigarettes for Harm Reduction in Smokers With Opioid Use Disorder
The purpose of this an open-label, randomized controlled trial study is to compare the effectiveness of electronic cigarettes (e-cigarettes/e-cigs) versus telehealth motivational counseling with combination nicotine replacement therapy (NRT) + telehealth counseling on combustible cigarettes smoking reduction among persons with opioid use disorder (OUD) in methadone and buprenorphine treatment programs (opioid use disorder treatment programs (OUDTP)). OUDTP patients are a population with exceptionally high combustible cigarettes smoking burden and yet limited success in achieving meaningful clinical outcomes in tobacco treatment. If effective, electronic cigarettes would provide an additional tool for tobacco harm reduction among this difficult-to-treat vulnerable population.
Gender: All
Ages: 21 Years - 75 Years
Updated: 2026-03-11
1 state
NCT06118502
A Clinical Trial of Adaptive Treatment for Early Smoking Cessation Relapse
This is a research study to find out if treatment decision making can be improved for smokers who find it difficult to quit with medications. Everyone who participates in this study will receive free product, either nicotine replacement therapies (patches and lozenges), varenicline, or a harm reduction product (e-cigarette) for a full 12 weeks. Most participants will receive some combination of these treatments, depending on individual response to each. All visits and study assessments will be entirely remote. All treatments will be provided free of charge for the first 12 weeks. After that, the study team will contact the participants 6 months after the first study phone call to complete another survey. The study lasts six months and will involve 8 surveys.
Gender: All
Ages: 21 Years - Any
Updated: 2026-03-06
1 state
NCT06264154
The Role of Flavor in the Substitutability of E-cigarettes for Combustible Cigarettes Among Persistent Smokers
This between-subjects study aims to evaluate the effect of flavor on initial and sustained switching from combustible cigarettes to e-cigarettes among 210 cigarette smokers. After measuring baseline cigarette smoking rate, participants will be randomized to a six-week regimen of fruit-flavored, tobacco-flavored, or menthol-flavored e-cigarettes and be instructed to switch (versus smoking cigarettes) over a 6-week period. Flavor-associated subjective reward and the reinforcing value of flavored e-cigarettes relative to combustible cigarettes will be assessed as mechanisms.
Gender: All
Ages: 21 Years - Any
Updated: 2026-02-19
1 state
NCT05641974
Effect of Helpers Program On-line Training on Smoking Relapse and Social Networks
The purpose of this study is to assess the effect of the Helpers Stay Quit training on abstinence over time of newly abstinent smokers, and on the interactions they have with their personal network related to smoking and smoking cessation.
Gender: All
Ages: 18 Years - 99 Years
Updated: 2026-02-12
1 state
NCT06173778
Semaglutide for Post-Smoking Cessation Weight Management
This trial will examine the effect of semaglutide 2.4mg on changes in body weight, body composition, and peripheral and central mechanisms that control appetite, satiety, and food intake in the context of smoking cessation.
Gender: All
Ages: 18 Years - 75 Years
Updated: 2026-02-11
1 state
NCT06295757
Effects of Relighting on Smoke Toxicant Deliveries and Subjective Smoking Measures
Characterize effects of relighting on smoke toxicant deliveries and subjective smoking measures. This will be a within-subject comparison in a single experimental group of 30 smokers who report engaging in relighting behaviors. We will assess smoking intensity for relit and non-relit (i.e., smoked continuously without relighting) cigarettes in the natural environment and will conduct in-clinic measurements of smoking topography and subjective responses for relit and non-relit cigarettes. Information on relighting patterns and smoking topography collected from each participant will be used to compare machine-measured smoke yields of key harmful constituents when their usual cigarettes are smoked with and without relighting. Hypothesis: Relit cigarettes will produce higher levels of toxicants than non-relit cigarettes.
Gender: All
Ages: 21 Years - Any
Updated: 2026-02-04
1 state
NCT06395415
Development of a Mobile Health Intervention for Electronic Cigarette Use Among Young Adults
Electronic Nicotine Delivery Systems (ENDS) use remains prevalent among young adults, and many have high interest in quitting, yet research on effective intervention is lacking. A mobile health (mHealth) intervention that translates effective smoking cessation materials and pharmacotherapy may be a promising avenue for intervention. The initial phase of the proposed study uses a pilot study to evaluate a novel mHealth intervention for young adult ENDS and dual product (ENDS and combustible cigarette) users.
Gender: All
Ages: 18 Years - 26 Years
Updated: 2026-01-30
1 state
NCT07356297
Remote Interventions for Menthol Cigarette Use
The purpose of this study is to evaluate whether a digital, incentive-based program, used in conjunction with traditional quitline (QL) services, can be beneficial to quitline callers who smoke menthol cigarettes. The services evaluated focus on coaching, support, and/or incentives for individuals who wish to quit smoking.
Gender: All
Ages: 18 Years - Any
Updated: 2026-01-21
NCT06609083
Effect of Cannabis on Cigarette Use Behavior
The purpose of this study is to determine the impact of tetrahydrocannabinol (THC) administration on motivational, subjective, and physiological effects of cigarettes. The study's goals are to test demand for cigarettes, tobacco craving, affect, heart rate, blood pressure, expired breath carbon monoxide, and cognitive performance. Researchers will compare multiple doses of THC and a placebo in participants who smoke cigarettes and either smoke or vape THC in the laboratory.
Gender: All
Ages: 21 Years - Any
Updated: 2026-01-16
1 state
NCT07161050
Effects of a Low Nicotine Standard and Tobacco Prices on Illegal Cigarette Purchasing
This study will investigate the effects of a very-low-nicotine cigarette (VLNC) standard, e-cigarette price, and illegal cigarette price on illegal product purchasing and alternative product use in a virtual marketplace.
Gender: All
Ages: 21 Years - Any
Updated: 2026-01-16
1 state
NCT07199517
Catalyzing Cigarette Smoking Cessation Through Harm Reduction Sampling Among People Unmotivated to Quit
This study aims to investigate harm-reduction sampling in a choice format versus medicinal nicotine sampling on smoking behavior, identify mechanisms of sampling's effects, and explore moderators of these effects among a national sample of people unmotivated to quit smoking. Participants will be randomized 2:1 to choose one of three harm-reduction products (ECIG, IQOS, ONP) versus a medicinal nicotine control condition (nicotine patch + lozenge, NPL), receive a 4-week starter product regimen, and then be followed for 6 months to assess use behavior.
Gender: All
Ages: 21 Years - Any
Updated: 2026-01-13
1 state
NCT06678789
Evaluation of Low and High Nicotine Tobacco Free Nicotine Pouches
Tobacco-free oral nicotine pouches (such as Zyn brand) are a less harmful alternative to cigarette smoking. Pouches, however, contain nicotine, and addictive substance that is not risk-free. The present study is evaluating how well nicotine pouches, at different nicotine levels, help people switch away from smoking cigarettes. People who smoke cigarettes will be asked to answer questions about their tobacco product use and provide breath samples and cheek swab samples at an in-person visit to MUSC Charleston. Participants will then be provided with a 28-day supply of nicotine pouches, and will be asked to switch from smoking to pouches over the course of 4 weeks. Finally, participants will complete a final visit at MUSC, and will answer more questions about their tobacco use 1-month later.
Gender: All
Ages: 21 Years - Any
Updated: 2025-12-18
1 state
NCT05815199
E-cigarettes for Harm Reduction Among Smokers With Serious Mental Illness
In this open-label, randomized controlled trial study, participants who smoke combustible cigarettes (CC) and are diagnosed with Serious Mental Illness (SMI) will be randomized in two arms to receive harm-reduction counseling and Ecological Momentary Intervention text messaging (EMI) along with either e-cigarettes (EC) or nicotine replacement therapy (NRT) such as patch and lozenges to compare the efficacy in CC smoking reduction.
Gender: All
Ages: 21 Years - Any
Updated: 2025-10-10
1 state
NCT07142668
Effects of Tax Proposals and Cigarette Availability on Tobacco Purchasing
This study will investigate the effects of normal-nicotine versus low-nicotine cigarette availability in the context of four tax proposals (Tobacco Parity, Nicotine-Content, Harm-Reduction, and Modified Risk Tobacco Product-based taxes) on tobacco product purchasing patterns in a virtual marketplace.
Gender: All
Ages: 21 Years - Any
Updated: 2025-09-05
2 states
NCT05233228
Mobile Health Technology for Personalized Tobacco Cessation Support in Laos
In Lao People's Democratic Republic (Lao PDR), 51% of adult men and 7% of adult women smoke tobacco. The development and evaluation of sustainable tobacco cessation interventions suitable for widespread adoption in nations such as Lao PDR are pressing public health needs. To address this need, the investigators propose a project that adapts a theoretically and empirically based mobile health (mHealth) technology to help people quit smoking cigarettes in Lao PDR. This mHealth approach includes a fully automated, interactive, personalized, smartphone-delivered intervention for behavioral treatment, delivered through our Insight™ platform. This proposed project for Lao PDR includes 2 main phases. In the R21 Phase, the investigators will use formative research methods to adapt our intervention content to the sociocultural context, language, and communication styles of Laotians. In the subsequent R33 Phase, the investigators will conduct a randomized controlled trial (RCT) to evaluate the efficacy of our mHealth intervention and technology. Adult smokers of both sexes will be recruited through 2 large hospitals: Setthathirath Hospital in Vientiane and Champasak Hospital in Champasak Province. Participants (n=500) will be randomized to 1 of 2 treatment groups: Standard Care (SC; n=250) or Automated Treatment (AT; n=250). SC consists of brief advice to quit smoking delivered by research staff, self-help written materials, and a 2-week supply of NRT (transdermal patches). AT consists of all SC components plus a fully automated smartphone-based treatment program that involves interactive and personalized proactive messages, images, or videos. The primary health outcome of the trial is biochemically confirmed self-reported 7-day point prevalence abstinence 12 months post study enrollment. The project also aims to advance mHealth research capacity in Lao PDR and sustain the US-Lao PDR research network. The project has the potential to transform healthcare services for tobacco cessation treatment throughout the country and, ultimately, to reduce tobacco-induced morbidity and mortality significantly.
Gender: All
Ages: 18 Years - 65 Years
Updated: 2025-08-15
NCT03750825
Are Smokers Switching to Vaping at Lower Risk for Cancer? (Electronic Cigarettes and Cancer Risk)
This project will address a growing public health concern, namely, the health risks or benefits of e-cig use relative to cigarette smoking. The investigators will use biomarkers of early effects of relevance to cancer to determine the carcinogenic potential of e-cig use relative to cigarette smoking in oral epithelium, which is a target tissue for smoking-associated cancer. The study population will consist of one group of smokers who are interested in switching to e-cig use (Grp 1), one group of smokers who do not intend to change their smoking habits (Grp 2), and one group of non-users who would like to maintain their nonsmoking non-vaping status (Grp 3); The total number of participants in this project is 150 (n = 50, each group). The investigators will use an integrative 'multi-omics' approach complemented with single-locus/gene validation analyses to detect temporal changes in the genome, epigenome, and transcriptome relevant to cancer in the oral cells of the participants as the intervention progresses.
Gender: All
Ages: 22 Years - 55 Years
Updated: 2025-08-06
1 state
NCT06373679
Switch or Quit R01
This study evaluates whether non-cigarette tobacco products (e-cigarettes) can help smokers quit smoking as compared to traditional quit methods (nicotine replacement therapy or varenicline/Chantix). Participants in this study will be randomly assigned to one of two groups, then will have a choice between the offered products of that group. Participants in the e-cigarette group will have a choice of e-cigarette brand and flavor. Participants in the medication group will have choice between nicotine replacement therapy (patches and lozenges) or varenicline, also known as Chantix. Participation will last 6 months and will include weekly phone calls for the initial 7-weeks plus a 11-week phone call and a 6-month follow-up visit. Participants will also complete electronic daily diaries during the first 7-weeks.
Gender: All
Ages: 21 Years - Any
Updated: 2025-07-25
1 state
NCT01926041
The Effectiveness of Smoking Cessation in Prediabetic Smokers
Existing literature investigating the impact of smoking cessation on new-onset diabetes mellitus (DM) risk is conflicting. Combing the need for smoking cessation and body weight self-management to prevent the progression of prediabetes stage into DM, with the public implementation of the second-generation cessation program, we aimed to study the effectiveness of the Fight Tobacco and Stay Fit (FIT2) program aiming at promoting smoking cessation and restricting post-cessation weight gain (PCWG) together in prediabetic smokers regarding long-term glycemic and DM-related health outcomes.
Gender: All
Ages: 30 Years - 75 Years
Updated: 2025-06-24
1 state
NCT07014124
Smoking Cessation for Fathers of Sick Children
The project aims to develop and examine the feasibility, acceptability, and preliminary effectiveness of a proactive intervention model combined brief advice, nicotine replacement therapy sampling and mHealth-based individual counselling in increasing smoking abstinence for fathers of sick children.
Gender: MALE
Ages: 18 Years - Any
Updated: 2025-06-10
1 state
NCT06027840
Concurrent vs. Sequential Cessation of Dual Cigarette and E-cigarette Use
The purpose of this research study is to understand whether concurrent treatment for cigarettes and e-cigarettes in which an individual quits both products at the same time (QUIT-C) or sequential treatment in which an individual quits cigarettes first followed by e-cigarettes is more effective for quitting both products. The study will also compare the effect of treatment on health-related biomarkers. All participants will receive varenicline, a medication used to treat tobacco use dependence, counseling, and cessation resources (i.e., links to text-based support, self-change booklet). Varenicline helps to reduce cravings for tobacco use and decreases the pleasurable effects of cigarettes and other tobacco products.
Gender: All
Ages: 18 Years - Any
Updated: 2025-05-06
1 state
NCT06232447
Menthol, Inflammation, and Nicotine Transition Study
This study will focus on examining the potential impact of menthol flavoring in cigarettes on biomarkers of systemic inflammation as a subclinical indicator of cardiovascular disease risk.
Gender: All
Ages: 21 Years - 85 Years
Updated: 2025-04-17
1 state
NCT04903028
RTMS Targets Neural Circuits for Smoking Cessation
Cigarette smoking is a significant public health concern. Transcranial magnetic stimulation (TMS) is a non-invasive form of brain stimulation that has already displayed remarkable potential for producing novel, non-pharmacological interventions for depression and cigarette smokers. In this study, investigators will use brain MRI to guide TMS therapy for smoking cessation.
Gender: All
Ages: 22 Years - 70 Years
Updated: 2025-04-10
1 state