Reduced nicotine content cigarettes: effects on toxicant exposure, dependence and cessation

Associations between compliance with very low nicotine content (VLNC) cigarettes, abstinence self-efficacy, and quit outcomes in a pilot smoking cessation trial

BACKGROUND

Switching to Very Low Nicotine Content (VLNC) cigarettes reduces toxicant exposure and nicotine dependence, and may improve smoking cessation. However, non-compliance with VLNCs is often high, which may reduce their effectiveness. Here, we conducted secondary analyses of a pilot smoking cessation trial utilizing VLNCs to examine associations between pre-cessation VLNC compliance and changes in smoking rate, dependence, and abstinence self-efficacy, as well as quit outcomes.

METHODS

People who smoke daily (n=35) engaged in a 4-week pre-cessation intervention including VLNCs, transdermal nicotine patch, and behavioral counseling. After quit date, participants received 8 weeks of nicotine replacement therapy and 4 additional behavioral sessions, and were followed for 10 weeks to assess abstinence. Compliance with VLNCs was assessed biweekly during pre-cessation using timeline follow-back. Statistical analyses examined associations between VLNC compliance and a) changes in smoking rate, dependence and abstinence self-efficacy over the course of study cigarette use; and b) time to relapse, controlling for other smoking variables.

RESULTS

Greater compliance during the second half of study cigarette use was associated with subsequent improvement in self-efficacy (p<.05). Increased self-efficacy and VLNC compliance both predicted lower likelihood of relapse. Nicotine dependence and cigarettes per day both decreased following study cigarette use, but were unrelated to compliance or relapse.

CONCLUSIONS

Compliance with VLNCs prior to quitting increased abstinence self-efficacy and predicted better quit outcomes above and beyond baseline smoking characteristics. Although preliminary, these findings suggest that identifying strategies to promote exclusive use of VLNCs during a brief pre-cessation window may be beneficial.

Dietary Patterns among Smokers and Non-Smokers: Findings from the National Health and Nutritional Examination Survey (NHANES) 2017-2018

Diet behavior and nutrition are critical for maintaining health and improving quality of life. Cigarette smoking remains the leading cause of preventable death in the United States. Poor dietary choices, such as excessively frequenting restaurants, consuming ready-to-eat foods from grocery stores, and ingesting ultra-processed foods (like frozen meals and pizzas), can adversely impact health. Despite this, research comparing dietary behaviors between smokers and non-smokers is limited. Using data from the National Health and Nutritional Examination Survey 2017-2018, we analyzed diet behavior based on smoking status. Our findings reveal that smokers had a significant increase (90%) in the frequency of consuming frozen meals/pizzas in the past 30 days compared to non-smokers (coefficient: 1.9; 95% CI: 1.4, 2.6; p-value < 0.001). Additionally, over 70% of participants, regardless of their smoking status, were unaware of MyPlate, a nutritional guide created by the United States Department of Agriculture (USDA) to encourage Americans to make healthier food choices. There is an urgent need to increase public awareness of MyPlate and promote a better understanding of healthy dietary behaviors.

Rapid-response surveillance of the first US test market for VLN cigarettes

INTRODUCTION

VLN King menthol and non-menthol are the first combustible cigarettes to receive US Food and Drug Administration (FDA) authorisation as modified risk tobacco products. Focusing on the first retail test market, this study characterised VLN advertising, product placement, discounts and price.

METHODS

All Chicago-area Circle K stores (n=133) were telephoned to assess whether they sold VLN. Single-pack price of non-menthol was obtained in 57 of 100 stores that sold VLN. In fall 2022, trained data collectors visited those 57 stores to assess VLN product placement, advertising, discounts and prices. Paired t-tests compared observed VLN price with telephone price and to price of other cigarette brands.

RESULTS

Nearly all stores (91.1%) displayed exterior advertisements for VLN, and 41.1% displayed interior advertising, with 8.9% of stores advertising VLN in the power wall but never in the header row. VLN cigarettes were displayed in the power wall exclusively and among high-nicotine cigarettes. Some VLN marketing claims were not FDA-authorised. VLN advertised a sweepstakes offer and rewards programme. Most stores (85.7%) offered VLN discounts. VLN was priced like a premium brand (mean=$10.90, SD=$1.53), and prices obtained by telephone did not differ from observed prices several months later.

CONCLUSIONS

Retail marketing strategies for VLN mimic those for high-nicotine cigarettes. Deviations from FDA-authorised marketing claims were evident. Surveillance in future test markets is recommended to assess compliance with marketing claims and examine relative price and discount offers. Of interest is how premium-priced, low-nicotine cigarettes stand to compete in a market dominated by cheaper high-nicotine cigarettes.

Perceptions of the Addictiveness of Low-Nicotine Cigarettes Versus Typical Cigarettes and Exposure to Tobacco Industry-Sponsored Corrective Campaign

BACKGROUND

In 2017, the U.S. Food and Drug Administration (FDA) announced a regulatory plan to reduce the nicotine content of cigarettes. This study examines the association of exposure to industry-sponsored corrective statements on perceptions of the addictiveness of low-nicotine cigarettes relative to typical cigarettes within the general US population.

METHODS

The study comprised 4975 US adult respondents of the 2019 Health Information National Trends Survey (HINTS 5, Cycle 3). Multinomial logistic regression models were used to examine associations between exposure to tobacco industry corrective messages and perceptions of the addictiveness of low-nicotine cigarettes relative to typical cigarettes.

RESULTS

In the overall population, 4.1% reported that low-nicotine cigarettes were much more addictive than typical cigarettes, 67.5% said they were equally addictive, while 28.4% reported they were slightly/much less addictive. Adults exposed to industry-sponsored corrective messages had higher odds of perceiving low-nicotine cigarettes as equally addictive as typical cigarettes (aOR 1.57; 95% CI, 1.13-2.19) than those who saw no corrective messages. Those exposed to the corrective messages specifically about the addictiveness of smoking and nicotine had higher odds of perceiving low-nicotine cigarettes as equally addictive as typical cigarettes (aOR, 1.73; 95% CI, 1.07-2.81) compared to those who saw no corrective message.

CONCLUSIONS

Our findings suggest that exposure to court-ordered tobacco industry corrective statements may have reinforced perceptions on the addictive potential of nicotine. However, study findings indicate a need for campaigns specifically tailored to address misperceptions observed in this study.

A randomized controlled trial of potential tobacco policies prohibiting menthol flavor in cigarettes and e-cigarettes: a study protocol

BACKGROUND

Menthol cigarette use remains a large public health problem and disproportionately affects Black adults in the United States. The Food and Drug Administration has proposed prohibiting menthol flavor in cigarettes to protect public health. However, e-cigarettes are available in menthol flavor and are a popular alternative product adults might switch to if menthol is prohibited in cigarettes. Research is needed to understand how availability of menthol (vs. tobacco) flavored e-cigarettes could impact cigarette use among adults who smoke menthol cigarettes.

METHODS

We will recruit 150 adults who currently smoke menthol cigarettes and will randomize them to 1 of 3 conditions modeling different regulatory scenarios. We will recruit equal numbers of participants identifying as Black vs. non-Black and will stratify randomization by race. To promote standardization and adherence, cigarette and e-cigarette products will be provided for 8 weeks based on the assigned condition: (A) no menthol restriction (menthol cigarette and menthol flavored e-cigarette), (B) menthol prohibited in cigarettes only (non-menthol cigarette and menthol flavored e-cigarette), (C) menthol prohibited in both cigarettes and e-cigarettes (non-menthol cigarette and tobacco flavored e-cigarette). A follow-up visit will occur at week 12 to assess tobacco use status. The study aims are to (1) examine the impact of prohibiting menthol flavor in cigarettes and e-cigarettes on smoking behavior and (2) investigate whether outcomes differ by race to understand the impact of menthol policies on Black (vs. non-Black) individuals given high rates of menthol cigarette use in this population. The primary outcome will evaluate changes in the number of cigarettes smoked per day during the 8-week study period and will examine differences by regulatory scenario. Secondary outcomes will compare percent days smoke-free, changes in nicotine dependence, and motivation, confidence, and intentions to quit smoking by the regulatory scenarios. We will examine whether changes in the outcomes differ by Black vs. non-Black participants to compare the magnitude of the effect of the various menthol policy scenarios by race.

DISCUSSION

Results will contribute critical information regarding menthol in cigarettes and e-cigarettes to inform regulatory policies that maximize reductions in cigarette smoking and reduce tobacco-related health disparities.

TRIAL REGISTRATION

NCT05259566. Yale IRB protocol #2000032211, last approved 12/8/2023.

Testing messaging strategies to correct beliefs about nicotine and relative harm perceptions of non-cigarette tobacco products compared to cigarettes: A 2 × 2 factorial experiment of factsheets

INTRODUCTION

The misperception that nicotine is a major cause of cancer is common and may relate to inaccurate relative harm perceptions about tobacco products. To assess if messaging can correct these misperceptions, we tested factsheets that manipulated presences vs absence of (1) a causal alternative (i.e., combustion, not nicotine, causes disease) and/or (2) a reason for the misinformation (i.e., nicotine is the focus of many health messages).

METHODS

We used an online 2 × 2 factorial experiment of n = 193 adults who smoke and believe nicotine causes cancer to assess the effect of different message strategies on perceptions of tobacco products and switch intention. Pre-post differences and between-condition differences were assessed.

RESULTS

Strength of agreement with the statement that nicotine is a major cause of cancer decreased and switch intentions increased after message exposure. The proportion of participants with low relative harm perceptions increased for e-cigarettes and smokeless tobacco (p <.0001) and decreased for very low nicotine cigarettes compared to cigarettes. The message with both strategies decreased agreement that nicotine causes cancer more than the message with only the causal alternative. There was no significant effect of condition on relative harm beliefs or switch intentions.

CONCLUSIONS

Messages with both corrective strategies can reduce the belief that nicotine causes cancer to a greater extent than messaging that only contains a causal alternative. Belief accuracy increased after any message exposure, but these findings should be interpreted cautiously given the study design. Combined strategies should be further investigated in larger samples.

Society for Research on Nicotine and Tobacco as an Outgrowth of the 1988 Surgeon General's Report on Nicotine Addiction: Reflections of the Early Presidents

INTRODUCTION

The Society for Research on Nicotine and Tobacco began in the United States as a scientific organization "to stimulate the generation and dissemination of new knowledge concerning nicotine and tobacco in all its manifestations." Now in its 30th year, the Society is taking on new challenges in tobacco control, nicotine vaping, product regulation, and public policy.

AIMS AND METHODS

This Review describes the formative years of the Society from the perspective of researchers who were in leadership positions during that time, documenting how biobehavioral and clinical research in the first 10 years was a continuation of the scientific mission of the 1988 United States Surgeon General's Report on Nicotine Addiction and summarizing organizational innovations during each president's term of office.

CONCLUSIONS

The Society's promotion of scientific research served as a catalyst for funding, policy, and regulation, setting the stage for its influence and credibility.

IMPLICATIONS

This Commentary provides context and an overview of the scientific research and the organizational innovations that occurred during the early years of the Society for Research on Nicotine and Tobacco using publications and available documentation. The Society was able to thrive because biobehavioral research on nicotine addiction provided the scientific underpinnings for the tobacco control enterprise as a whole. The objective of this Commentary is to describe formative events in the Society's history based on the accomplishments of its early leaders.

Nicotine beliefs and perceptions of low nicotine labels and mitigating statements among people who do and do not smoke: a cross-sectional study from Aotearoa New Zealand

BACKGROUND

Aotearoa New Zealand proposed a new maximum nicotine content of 0.8 mg/g for smoked tobacco products, although the new government plans to repeal this legislation. Requiring 'Very low nicotine' (VLN) messages on cigarettes meeting this standard may reinforce misperceptions that they are less harmful than cigarettes currently sold.

METHODS

To explore knowledge of nicotine and very low nicotine cigarettes (VLNCs), and perceptions of cigarette packs featuring different low nicotine messages (eg, 'Very low nicotine') and mitigating statements (eg, 'No cigarettes are safe'), we surveyed 354 people who smoked, 142 who formerly smoked, and 214 people who had never smoked regularly.

RESULTS

Around half of all respondents believed VLNCs were less harmful than regular cigarettes and around two-thirds incorrectly thought nicotine causes most of the related health problems resulting from smoking. Nearly a third thought VLNCs would be less harmful than regular cigarettes; 34% believed they would be just as harmful. Mitigating statements did not affect perceptions of people who smoked, although people who formerly, or who had never smoked regularly, perceived mitigating statements referring to poisons and cancer as significantly more likely than the VLN message to discourage smoking.

CONCLUSIONS

Misunderstanding of VLNCs as less harmful than regular cigarettes is widespread; VLN messages may reinforce this misperception, which mitigating statements did not correct among people who smoke. As an alternative to VLN messages, policy makers could consider introducing VLNCs on a specified date and developing public information campaigns; these measures would avoid phase-in confusion and obviate the need for VLN messaging.

Effect of nicotine expectancy and nicotine dose reduction on cigarette demand, withdrawal alleviation, and puff topography

BACKGROUND

Current FDA plans include proposed nicotine reduction mandates by the end of 2023. Most research on reduced nicotine cigarettes has been dose-blinded, while a mandate would be known to the public. Few laboratory studies have examined specifically how low nicotine content labeling impacts behavioral response. The purpose of this within-subject, balanced-placebo, human laboratory study was to evaluate the main and interactive effects of nicotine dose expectancy and dose reduction on cigarette reinforcement, withdrawal alleviation, and puff topography.

METHODS

Participants who smoke daily (N=21; 9 female) completed one practice and four experimental sessions in which expectancy (labeled "average" versus "very low" nicotine) and nicotine dose (0.80mg versus 0.03mg yield) were manipulated. Participants in acute withdrawal sampled experimental cigarettes followed by withdrawal alleviation and puff topography measures. Cigarette demand was measured using an incentivized purchase task. Analyses evaluated main and interactive effects of expectancy and nicotine dose.

RESULTS

Nicotine dose manipulation produced expected physiological effects (e.g., heart rate increases) and both reduced nicotine dose and expectation manipulations reduced perceived nicotine content. Expectation of reduced nicotine alone or in combination with reduced nicotine dose did not alter demand, withdrawal alleviation, or topography. Effective withdrawal alleviation was observed in all conditions.

CONCLUSIONS

These data inform nicotine regulation policy by suggesting limited compensatory harms caused by reduced nicotine expectations. The minimal acute effects of reduced nicotine expectancy or exposure on demand suggests that reduced nicotine standards are likely to generate their greatest public health benefit through the slowing of newly initiating cigarette smoking.

Disparities in Healthcare and HBV Vaccination by Smoking Status: Findings from the National Health and Nutrition Examination Survey (NHANES) 2017-2018

Cigarette smokers face greater challenges in accessing healthcare compared with non-smokers. In the US, approximately 2.2 million individuals are chronically infected with hepatitis B virus (HBV). I used data from the National Health and Nutrition Examination Survey (NHANES) 2017-2018 to investigate the association between smoking status (current, former, and never smoker) and different health outcomes, including healthcare accessibility, HBV vaccination, general health condition, and health insurance. Multivariable logistic regressions were used to analyze healthcare disparity by smoking status. I found that current smokers had 40% higher odds (AOR = 1.4, 95% CI: 1.1, 1.8) of lacking routine healthcare access compared with non-smokers. Regardless of smoking status, I observed a high rate of HBV non-vaccination among all participants. Specifically, 64% of current smokers, 67% of former smokers, and 57% of non-smokers had not received a single dose of HBV immunization. My study sheds light on the persisting gaps in healthcare access, particularly for smokers, and the urgent need to promote awareness and vaccination against hepatitis B.

Practical guidance on modeling choices for the virtual twins method

Individuals can vary drastically in their response to the same treatment, and this heterogeneity has driven the push for more personalized medicine. Accurate and interpretable methods to identify subgroups that respond to the treatment differently from the population average are necessary to achieving this goal. The Virtual Twins (VT) method is a highly cited and implemented method for subgroup identification because of its intuitive framework. However, since its initial publication, many researchers still rely heavily on the authors' initial modeling suggestions without examining newer and more powerful alternatives. This leaves much of the potential of the method untapped. We comprehensively evaluate the performance of VT with different combinations of methods in each of its component steps, under a collection of linear and nonlinear problem settings. Our simulations show that the method choice for Step 1 of VT, in which dense models with high predictive performance are fit for the potential outcomes, is highly influential in the overall accuracy of the method, and Superlearner is a promising choice. We illustrate our findings by using VT to identify subgroups with heterogeneous treatment effects in a randomized, double-blind trial of very low nicotine content cigarettes.

An Open-label Pilot Study of NicoBloc as a Novel Smoking Cessation Intervention

INTRODUCTION

NicoBloc is a viscous fluid applied to the cigarette filter designed to block tar and nicotine. This novel and understudied smoking cessation device presents a nonpharmacological means for smokers to gradually reduce nicotine and tar content while continuing to smoke their preferred brand of cigarette. This pilot study aimed to assess the feasibility, acceptability, and initial efficacy of NicoBloc as compared with nicotine replacement therapy (nicotine lozenge).

METHODS

A community sample of predominately Black smokers (N = 45; 66.7% Black) were randomized to receive NicoBloc or nicotine lozenge. Both groups engaged in 4 weeks of smoking cessation therapy followed by 2 months of independent usage with monthly check-ins to assess medication adherence. The intervention lasted 12 weeks, and the study concluded with a 1-month postintervention follow-up visit (week 16).

RESULTS

NicoBloc was comparable with nicotine lozenge in smoking reduction, feasibility, symptom adverse effects, and reported acceptability at week 16. Participants in the lozenge group endorsed higher treatment satisfaction ratings during the intervention and lower cigarette dependence. Adherence to NicoBloc was superior throughout the study.

CONCLUSION

NicoBloc was feasible and acceptable to community smokers. NicoBloc presents a unique, nonpharmacological intervention. Future research is needed to examine whether this intervention may be most effective in subpopulations where pharmacological approaches are restricted or in combination with established pharmacological methods such as nicotine replacement therapy.

Effect of very low nicotine content cigarettes on alcohol drinking and smoking among adult smokers who are at-risk alcohol drinkers

Alcohol and tobacco use are interrelated. This study examined response to very low nicotine content (VLNC) and moderate nicotine content (MNC) cigarettes by problematic drinking. We utilized a double-blind, randomized, within-subjects crossover design of VLNC and MNC cigarettes in two groups of adult cigarette smokers: with at-risk drinking (ARD; n = 23) and without ARD (n = 24). Participants smoked only their assigned experimental cigarette in their home environment for 7 days, and completed laboratory visits, including ad libitum smoking of the assigned experimental cigarette, at the beginning and end of each experimental week. Participants smoked their usual cigarettes for 7 days between conditions. Participants provided daily reports of alcohol and cigarette consumption. Current Diagnostic and Statistical Manual of Mental Disorders-5th edition (DSM-5) alcohol use disorder (AUD) was assessed at baseline and the end of each experimental week. Compliance with smoking of experimental cigarettes was good. Adjusting for baseline drinking, there was no significant effect of experimental cigarette or ARD group on drinks per day or alcohol urges. There was no effect of experimental cigarette or ARD group on cigarettes per day, or on any puff topography outcome or postsmoking exhaled carbon monoxide during laboratory smoking. No participant had a change in AUD status or AUD severity. After 7 days of exposure to VLNC cigarettes, adult cigarette smokers with ARD did not show compensatory drinking or compensatory smoking behavior. A future policy change in the United States to reduce nicotine content in cigarettes may not produce unintended compensatory drinking or smoking among this vulnerable and prevalent population of smokers. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

The Impact of Reducing Nicotine Content on Adolescent Cigarette Smoking and Nicotine Exposure: Results From a Randomized Controlled Trial

INTRODUCTION

As the science base around the potential benefits of a reduced-nicotine standard for cigarettes grows, information on the potential effects on adolescent smokers is a high priority. The aim of this randomized trial was to test the influence of 3-week exposure to reduced nicotine cigarettes in a sample of adolescent daily smokers.

AIMS AND METHODS

In this double-blind, two-arm, randomized controlled trial (NCT0258731), following a 1-week baseline, adolescent daily smokers not currently intending to quit (ages 15-19 years, n = 66 randomized) were urn randomized to use either very low nicotine content (VLNC; 0.4 mg/g; n = 33) or normal nicotine content (NNC, 15.8 mg/g; n = 33) research cigarettes for 3 weeks. Participants attended five study sessions at our clinical laboratory. The primary outcome was average total cigarettes smoked per day (CPD; including both study and non-study cigarettes) at week 3.

RESULTS

Stepwise regression results demonstrated that compared with NNC cigarettes (n = 31), assignment to VLNC cigarettes (n = 29), was associated with 2.4 fewer CPD on average than NNC assignment (p < .05) week 3 when controlling for covariates (p < .01, Cohen's d = 0.52 n = 60 completed all procedures). VLNC cigarettes were also associated with lower levels of craving reduction than NNC cigarettes (Questionnaire on Smoking Urges Factor 2, p < .05). No group differences were found for secondary outcomes.

CONCLUSIONS

Adolescent participants assigned to VLNC use for 3 weeks smoked fewer total CPD relative to the NNC group. Overall, data suggest that a VLNC policy would reduce cigarette smoking in adolescents who smoke, but high rates of incomplete adherence suggest that youth may seek alternative sources of nicotine in this scenario.

IMPLICATIONS

The US Food and Drug Administration may enact a reduced-nicotine product standard that would affect all commercially available cigarettes. One important population affected by this policy would be adolescents who smoke. This study, the first clinical trial of VLNC cigarettes in adolescents, demonstrates that adolescents switched to VLNC cigarettes for 3 weeks reduced their CPD relative to the normal-nicotine cigarette control group, without leading to increased respiratory symptoms or increased withdrawal. Biomarkers indicated the use of other sources of nicotine, suggesting that such a policy will need to consider approaches to assist in transitioning away from smoking.

Effects of advertising features on smokers' and non-smokers' perceptions of a reduced nicotine cigarette modified risk tobacco product

INTRODUCTION

Research is needed to determine the impact of marketing on perceptions and use of reduced nicotine content (RNC) cigarettes, particularly as US regulators have permitted the sale of an RNC cigarette modified risk tobacco product (MRTP) that seeks further authorisation to advertise using modified risk claims. This study examined the effects of two advertising elements (product name and disclaimer content) on perceptions of an RNC cigarette MRTP.

METHODS

Adult participants (n=807, 28.7% smokers, 58.2% male, 74.2% non-Latinx white) completed an online MTurk survey. Participants were randomised to view one of six RNC cigarette advertisements, using a 2×3 between-subject factorial design to manipulate product name ('Moonlight' vs 'Moonrise') and disclaimer content (industry-proposed: 'Nicotine is addictive. Less nicotine does NOT mean a safer cigarette' vs focused: 'Less nicotine does NOT mean a safer cigarette' vs no content), then completed recall and product perception questionnaires.

RESULTS

All participants who viewed the industry-proposed disclaimer (vs no content) perceived greater addiction risk (p's<0.05). Non-smokers who viewed this disclaimer also perceived greater health risks and held fewer false beliefs (p's<0.05). Smokers who viewed Moonlight (vs Moonrise) ads perceived lower health risks (p<0.05).

CONCLUSIONS

Disclaimer content may effectively inform consumers about addiction risk of a new RNC cigarette MRTP, and further inform non-smokers about health risks. This element, however, had little effect on perceived health risks among smokers, among whom the Moonlight product name was associated with health risk misperceptions similar to the banned 'light' descriptor.

Effect of restricting menthol flavored cigarettes or E-cigarettes on smoking behavior in menthol smokers

Bans of menthol characterizing flavor in tobacco products have been enacted in some localities and proposed in the United States for cigarettes. To gather data regarding how restrictions for menthol in cigarettes and e-cigarettes may affect current menthol cigarette smokers, 37 African American menthol smokers participated in a pilot study in which they were asked to abstain (n = 18) or not abstain from menthol cigarettes (n = 19) for 8-weeks. All participants received menthol flavored e-cigarettes for 4 weeks and tobacco flavored e-cigarettes for 4 weeks in random order. Number of cigarettes smoked per day (estimated mean ratio [EMR] = 0.31; 95% CI: 0.13, 0.72) and exhaled CO concentrations (EMR = 0.61; 95% CI: 0.43, 0.88) were lower in the menthol cigarette abstainer group compared to the menthol cigarette non-abstainer group. Those in the menthol cigarette abstainer group reported higher scores on motivation to quit (p = 0.03) and perceived effectiveness of quitting skills (p = 0.02). There were no substantial effects seen in amount smoked or exhaled CO based on flavor of e-cigarettes provided. Higher e-cigarette use (based on reported puffs per day) was reported in the menthol cigarette abstainer (vs. non-abstainer) group (p < 0.01) and also during the 4-week period when provided with menthol (vs. tobacco) e-cigarettes (p < 0.01). These data suggest that the potential of e-cigarettes to reduce tobacco related harm may be enhanced if combined with a ban on menthol flavor in combustible cigarettes. Larger studies are needed to determine the effect of limiting menthol in e-cigarettes on smoking behavior among current menthol smokers.

Impact of a reduced nicotine standard on young adult appeal for menthol and non-menthol cigarettes

INTRODUCTION

The Food and Drug Administration (FDA) announced its intention to reduce the nicotine content in cigarettes as a strategy to promote cessation and reduce smoking-related harm. A low nicotine product standard will apply to all cigarettes on the market, including menthol cigarettes. In December 2021, the FDA approved a modified risk tobacco product application for menthol and non-menthol flavoured very low nicotine cigarettes (VLNC) from the 22nd Century Group. Notably, experimentation with menthol cigarettes is linked to smoking progression, as well as greater nicotine dependence relative to non-menthol cigarette use. If menthol VLNCs are perceived as more appealing than non-menthol VLNCs, this would indicate that some aspect of menthol may maintain smoking even in the absence of nicotine and FDA's regulatory authority to ban or restrict the sale of menthol cigarettes should apply to reduced nicotine content of cigarettes. In April 2022, the FDA announced proposed rulemaking to prohibit menthol cigarettes, however it is unclear if a menthol prohibition would apply to VLNCs.

METHODS AND ANALYSIS

This study will recruit 172 young adult menthol smokers (with a specific subsample of n=40 sexual and gender minority young adults) and measure appeal for smoking experimental menthol and non-menthol VLNCs, and the impact of proposed product standards on tobacco product purchasing behaviour using an Experimental Tobacco Marketplace. Appeal across product standards will be assessed in a controlled laboratory and using ecological momentary assessment.

ETHICS AND DISSEMINATION

The protocol was approved by the University of Oklahoma Health Sciences Center Institutional Review Board (#11865). Findings will examine the effects of a reduced nicotine standard and a menthol ban on young adult smoking and will be disseminated through peer-reviewed journal articles and presentations at scientific conferences.

TRIAL REGISTRATION NUMBER

NCT04340947.

The effects of reduced nicotine content cigarettes on biomarkers of nicotine and toxicant exposure, smoking behavior and psychiatric symptoms in smokers with mood or anxiety disorders: A double-blind randomized trial

BACKGROUND

The U.S. Food and Drug Administration and the government of New Zealand have proposed a reduction of the nicotine content in cigarettes to very low levels. This study examined the potential effects of this regulation in smokers with affective disorders.

METHODS

In a randomized controlled parallel group trial conducted at two sites in the USA (Penn State University, Hershey, PA and Massachusetts General Hospital, Boston, MA) 188 adult smokers with a current (n = 118) or lifetime (n = 70) anxiety or unipolar mood disorder, not planning to quit in the next 6 months, were randomly assigned (1:1) to smoke either Usual Nicotine Content (UNC) (11.6 mg nicotine/cigarette) research cigarettes, or Reduced Nicotine Content (RNC) research cigarettes where the nicotine content per cigarette was progressively reduced to 0.2 mg in five steps over 18 weeks. Participants were then offered the choice to either receive assistance to quit smoking, receive free research cigarettes, or resume using their own cigarette brand during a 12-week follow-up period. Main outcomes were biomarkers of nicotine and toxicant exposure, smoking behavior and dependence and severity of psychiatric symptoms. The pre-registered primary outcome was plasma cotinine.

RESULTS

A total of 143 (76.1%) randomized participants completed the randomized phase of the trial, 69 (73.4%) in the RNC group and 74 (78.8%) in the UNC group. After switching to the lowest nicotine content cigarettes, compared to smokers in the UNC group, at the last randomized visit the RNC group had significantly lower plasma cotinine (metabolite of nicotine): difference between groups, -175.7, 95% CI [-218.3, -133.1] ng/ml. Urine NNAL (metabolite of NNK, a lung carcinogen), exhaled carbon-monoxide, cigarette consumption, and cigarette dependence were also significantly lower in the RNC group than the UNC group. No between-group differences were found on a range of other biomarkers (e.g. 8-isoprostanes) or health indicators (e.g. blood pressure), or on 5 different psychiatric questionnaires, including the Kessler K6 measure of psychological distress. At the end of the subsequent 12-week treatment choice phase, those randomized to the RNC group were more likely to have quit smoking, based on initial intent-to-treat sample, n = 188 (18.1% RNC v 4.3% UNC, p = 0.004).

CONCLUSION

Reducing nicotine content in cigarettes to very low levels reduces some toxicant exposures and cigarette addiction and increases smoking cessation in smokers with mood and/or anxiety disorders, without worsening mental health.

TRIAL REGISTRATION

TRN: NCT01928758, registered August 21, 2013.

Investigation of exposure biomarkers in human plasma following differing levels of tobacco-specific N-nitrosamines and nicotine in cigarette smoke

Tobacco-specific N-nitrosamines (TSNAs) are strong carcinogens widely found in tobacco products, environmental tobacco smoke, lake, and wastewater. The main objective of this study was to investigate the effects of cigarette smoke with different yields of TSNAs (NNK, NNN, NAT, NAB) and nicotine on the levels of biomarkers of exposure in smokers' plasma. Three hundred healthy volunteers were recruited comprising 60 smokers of each of 3 mg, 8 mg and 10 mg ISO tar yield cigarettes and 60 smokers who smoked 10 mg, 8 mg, and 3 mg for 14 days sequentially and 60 non-smokers. All study participants were male, aged from 21 to 45 years old, and were recruited from a same unit in Hebei, China. We measured the levels of NNAL, NAT, NNN, NAB and cotinine in plasma from 240 smokers and 60 non-smokers using a novel method established by online two-dimensional solid phase extraction-liquid chromatography-tandem mass spectrometry. The results showed that NNAL, NAT, NNN, NAB and cotinine in the plasma of smokers smoking cigarette with low TSNAs and nicotine were lower than that with high TSNAs and nicotine. When smokers switched from higher to lower TSNA yields of cigarettes, their plasma NNAL, NAT, NNN, NAB levels significantly decreased. The plasma concentrations of NNAL were significantly correlated with those of cotinine, NNN, NAT and NAB for smokers (p < 0.001). Similarly, the plasma concentrations of cotinine were significantly correlated with those of NNN, NAT and NAB for smokers (p < 0.001). The plasma NNAL, NAT, NNN, NAB and cotinine levels for smokers were significantly higher than those for non-smokers. These findings suggested that the total NNAL, NNN, NAT, NAB and cotinine in plasma were valid and reliable biomarkers for human exposure to TSNAs and nicotine.

Effect of menthol on nicotine reduction: Pooled results from two double-blind randomized controlled trials

BACKGROUND

Menthol upregulates nicotinic acetylcholine receptors and is associated with tobacco dependence. The effects of menthol when smoking cigarettes with varying low nicotine content up to 98 % (e.g., non-addicting) less than commercial cigarettes is not well understood. The U.S. Food and Drug Administration is considering two tobacco product standards in cigarettes including banning menthol and reducing nicotine content. These new standards have the potential to significantly reduce smoking initiation and maintenance by limiting the mechanistic effects of nicotine and menthol on the brain.

METHODS

We conducted two parallel randomized clinical trials of gradually reduced nicotine in cigarettes from 11.6 mg down to 0.2 mg nicotine/cigarette (very low nicotine content; VLNC) vs. usual nicotine content (11.6 mg; UNC) over an 18-week period in people who smoke cigarettes with low socioeconomic status (SES) and mental health conditions.

RESULTS

Compared to UNC, VLNC was associated with significant reductions in cotinine, cigarettes per day, expired carbon monoxide levels, nicotine dependence and symptomology. These associations did not differ between menthol and non-menthol cigarettes, except people who smoke menthol cigarettes had less of a cotinine reduction in the SES trial. The pooled odds ratio of being adherent with using only VLNC study cigarettes in the gradual nicotine reduction arm for people who smoke non-menthol vs. menthol cigarettes was 2.6 (95 % CI:1.0, 6.4; p-value: 0.04).

CONCLUSIONS

When nicotine is lowered to non-addicting levels, the results indicate an independent effect of menthol on the need to sustain nicotine intake in addicted people who smoke cigarettes.

Exercise and Reduced Nicotine Content Cigarettes in Adult Female Smokers: A Pilot Trial

Background: Although Reduced Nicotine Cigarettes (RNC) are suggested to improve smoking cessation and cardiometabolic health in relation to cancer risk, the effectiveness of exercise training with RNC on smoking cessation and cardiometabolic health is unknown. Methods: Female smokers (N = 27) were randomized to: (1) usual nicotine cigarettes (i.e., control), (2) RNC or (3) RNC plus exercise treatment for 12 weeks. Smoking withdrawal symptoms (e.g., Wisconsin Smoking Withdrawal Scale) and cardiometabolic health (e.g., weight, VO2max, resting respiratory exchange ratio (RER), glucose, HOMA-IR) were examined before and after treatment. Results: Treatments had no differential effect on weight (p = 0.80; partial η2 = 0.29), VO2max (p = 0.20, partial η2 = 0.18), or total cholesterol/HDL ratios (p = 0.59, partial η2 = 0.06). However, RNC + Exercise tended to maintain RER (i.e., fat oxidation; p = 0.10, partial η2 = 0.10) as well as insulin resistance (p = 0.13, partial η2 = 0.25) and cortisol compared (p = 0.06, partial η2 = 0.30) with control and RNC. Increased VO2max was also associated with lower nicotine dependence scores (r = −0.50, p < 0.05). Conclusion: In this pilot study, improved fitness was associated with lower nicotine dependence. Additional work is warranted to examine the effects of exercise in smokers as a tool to improving smoking cessation and lower disease risk.

Effects of Very Low Nicotine Content Cigarette use on Cigarette Reinforcement among Smokers with Serious Mental Illness

BACKGROUND

Among people without psychiatric disorders who smoke, very low nicotine content (VLNC) cigarette use reduces cigarette reinforcement. Whether this is true of people with serious mental illness (SMI) who smoke is unknown. Using a hypothetical purchase task, we compared the effects of 6-week use of VLNC versus normal nicotine content (NNC) cigarettes on study cigarette and usual brand (UB) cigarette reinforcement among people with SMI who smoke.

METHODS

After a baseline period of UB cigarette use, participants with SMI (n = 58) were randomized to use NNC cigarettes (15.8 mg nicotine/g tobacco) or VLNC cigarettes (0.4 mg/g) for 6 weeks. At Week 6, they completed the CPT for both their assigned study cigarette and UB. The groups were compared on demand intensity (number of cigarettes purchased at no cost) and elasticity (rate of decline in demand as price increases) using extra sum-of-squares F-tests. The effects of treatment on demand indices while controlling for covariates were assessed using hierarchical regression.

RESULTS

At Week 6, intensity of demand for study cigarettes was lower and elasticity was higher for the VLNC group relative to the NNC group (p < 0.0001). Furthermore, intensity of demand for UB cigarettes was lower for participants in the VLNC group relative to participants in the NNC group (p < 0.01). When controlling for baseline cigarettes per day, intensity remained significantly different for study cigarettes and usual brand cigarettes at Week 6.

CONCLUSION

A nicotine reduction policy may reduce cigarette reinforcement in this vulnerable population.

A permutation procedure to detect heterogeneous treatments effects in randomized clinical trials while controlling the type I error rate

BACKGROUND/AIMS

Secondary analyses of randomized clinical trials often seek to identify subgroups with differential treatment effects. These discoveries can help guide individual treatment decisions based on patient characteristics and identify populations for which additional treatments are needed. Traditional analyses require researchers to pre-specify potential subgroups to reduce the risk of reporting spurious results. There is a need for methods that can detect such subgroups without a priori specification while allowing researchers to control the probability of falsely detecting heterogeneous subgroups when treatment effects are uniform across the study population.

METHODS

We propose a permutation procedure for tuning parameter selection that allows for type I error control when testing for heterogeneous treatment effects framed within the Virtual Twins procedure for subgroup identification. We verify that the type I error rate can be controlled at the nominal rate and investigate the power for detecting heterogeneous effects when present through extensive simulation studies. We apply our method to a secondary analysis of data from a randomized trial of very low nicotine content cigarettes.

RESULTS

In the absence of type I error control, the observed type I error rate for Virtual Twins was between 99% and 100%. In contrast, models tuned via the proposed permutation were able to control the type I error rate and detect heterogeneous effects when present. An application of our approach to a recently completed trial of very low nicotine content cigarettes identified several variables with potentially heterogeneous treatment effects.

CONCLUSIONS

The proposed permutation procedure allows researchers to engage in secondary analyses of clinical trials for treatment effect heterogeneity while maintaining the type I error rate without pre-specifying subgroups.

Educating the Public on the Health Risks of Very Low Nicotine Content Cigarettes: Results From a US-Based Convenience Sample

INTRODUCTION

US FDA issued an advance notice of proposed rulemaking to reduce nicotine in cigarettes. To maximize the benefits of this potential standard, very low nicotine content (VLNC) cigarettes must be communicated in a way that does not result in misperceptions.

AIMS AND METHODS

Adults (n = 567 who smoke; n = 610 non-smokers) from an online platform were randomized to a control message previously associated with accurate addictiveness perceptions of VLNC cigarettes but health misperceptions or to one of five messages that also included messaging on nicotine morbidity effects or VLNC cigarettes morbidity or mortality effects. p value <.01 was significant.

RESULTS

In participants who smoke, perceived lung cancer risk (responses: 1, very little risk to 10, very high risk) if smoked VLNC cigarettes regularly was higher in conditions that communicated mortality effects of VLNC cigarettes compared to the control (7.12-7.18 vs. 5.97, p values < .01). In non-smokers, perceived lung cancer risk was higher in all five message conditions when compared with the control (7.58-8.22 vs. 6.35, p values < .01). Proportion who responded accurately (ie, False) to the statement Cigarettes with 95% less nicotine are safer than cigarettes with normal nicotine levels was higher in conditions describing VLNC morbidity or mortality effects when compared with the control in both participants who smoke (52.04-67.37% vs. 30.85%, p values < .01) and do not smoke (62.50-72.38% vs. 32.00%, p values < .01).

CONCLUSIONS

Messaging on mortality effects of VLNC cigarettes (ie, cigarettes with 95% less nicotine are as deadly as current cigarettes) was associated with more accurate perceptions of the health risks of VLNC cigarettes than the control; however, misperceptions remained in one-third of participants.

IMPLICATIONS

One approach to communicating a VLNC cigarette standard to the public is to include messaging on the mortality effects of VLNC cigarettes. However, further study and possible refinement of this message condition are recommended since approximately one-third of participants exposed to this message still perceived VLNC cigarettes to be safer than normal nicotine content cigarettes.

The Effects of Immediate vs Gradual Reduction in Nicotine Content of Cigarettes on Smoking Behavior: An Ecological Momentary Assessment Study

BACKGROUND

In recent years, much research has examined the effects of various interventions and treatments for smoking cessation. The results suggest that interventions targeting changes of nicotine content can help smokers reduce tobacco use or quit smoking. A number of clinical studies show that smokers who received an immediate reduction in nicotine content to very low levels have significantly greater reductions in the number of cigarettes smoked and toxic substance exposure compared to those with gradual reductions. However, from the perspective of smoking craving, whether the immediate and gradual reduction in nicotine content reduce smoking by reducing cravings needs further investigation.

METHODS

74 eligible Participants were randomly allocated to one of the two experimental conditions: (1) immediate reduction to 0.1 mg of nicotine per cigarette (n = 40); (2) gradual reduction from 1.0 (0.8 g ~ 1.2 mg) to 0.1 mg of nicotine per cigarette (n = 34). All participants completed 1-week baseline period during which they smoked their usual cigarette, followed by 16-week of interventions. The primary outcomes included cigarette cravings and number of cigarettes smoked per day (CPD); secondary outcomes included the number of cigarette-free day and emotional states.

RESULTS

Among the 52 participants [51 (98.1%) men; mean (SD) age, 33.44 (6.71) years; mean (SD) CPD, 16.83 (9.94)] who completed the trial, significantly lower cravings for cigarettes were observed in the immediate (n = 25) vs. gradual nicotine reduction group (n = 27) in the morning (t = -2.072, p = 0.039) and after dinner (t = -2.056, p = 0.041). Compared with the baseline daily smoking, the number of cigarettes smoked per day was significantly reduced at the beginning of week 12 in the immediate nicotine reduction group (p = 0.001) and at week 16 in the gradual nicotine reduction group (p < 0.001). The number of participants with any cigarette-free day was not significantly different between the groups (p = 0.198). The number of cigarette-free days was significantly more in the immediate vs. gradual nicotine reduction group (p = 0.027).

CONCLUSIONS

The significantly lower cravings were observed in the immediate vs. gradual nicotine reduction group, and led to faster reduction in the number of CPD, and a significant increase in the number of cigarette-free days. These findings add to the evidence base for reduced nicotine content in cigarettes.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, identifier: ChiCTR2100048216.

A review of the evidence on cigarettes with reduced addictiveness potential

BACKGROUND

In May 2018, the Secretariat for the World Health Organization Framework Convention on Tobacco Control convened a meeting to discuss the potential for reducing the addictiveness of tobacco products. A central focus was to review research findings on the behavioral effects of reducing the addictiveness of cigarettes.

METHODS

This manuscript reports the results of a review of the behavioral science literature, updated through April 2021, with special attention to both the potential benefits and unintended consequences of reducing nicotine in cigarettes.

RESULTS

Available evidence suggests that reducing nicotine content in cigarettes to very low levels could benefit public health in three primary ways, by 1) decreasing uptake of regular smoking, 2) decreasing the amount people smoke, and 3) increasing the likelihood of smoking cessation. Current evidence also suggests that reducing nicotine in cigarettes may produce similar benefits across many important subpopulations of people who smoke, including those with psychiatric comorbidities, those who use other substances, those with low socioeconomic status, young people, people who smoke infrequently and people who prefer menthol cigarettes. Cigarette nicotine reduction could also lead to some undesirable outcomes, such as experiencing withdrawal, product manipulation, an illicit market, and harm misperceptions; strategies that may mitigate each are discussed.

CONCLUSION

Overall, behavioral research suggests product standards that limit the nicotine content of combusted tobacco products could render cigarettes and similar products less addictive. The availability of legal, non-combusted products that effectively substitute for cigarettes and the dissemination of public health campaigns that clarify misperceptions about the relationship between nicotine, tobacco and disease may facilitate the extent to which a nicotine reduction policy reduces smoking.

Reactions to reduced nicotine content cigarettes in a sample of young adult, low-frequency smokers

RATIONALE

Reducing nicotine content in cigarettes to ≤ 2.4 mg per g of tobacco [mg/g] reduces smoking behavior and toxicant exposure among adult daily smokers. However, cigarettes with similar nicotine content could support continued experimentation and smoking progression among young adults who smoke infrequently.

OBJECTIVES

This study evaluated the threshold for nicotine in cigarettes that produces reactions associated with smoking progression in a sample of young adults who smoke infrequently.

METHODS

Young adults (n = 87, 18-25 years, 49% female) using tobacco products ≤ 15 days per month completed three counterbalanced, double-blinded sessions, each measuring positive and negative subjective reactions to fixed doses of smoke from investigational cigarettes containing one of three different nicotine contents: normal (NNC; 15.8 mg/g); very low (VLNC; 0.4 mg/g); and intermediate (INC; 2.4 mg/g). In a final session, participants chose one of the cigarettes to self-administer.

RESULTS

Post-cigarette breath carbon monoxide was greater for VLNC than for NNC (p < 0.001). Positive reactions were greater for NNC than INC (p < 0.001) and for INC than VLNC (p = 0.001). Negative reactions were greater for NNC than INC and VLNC (both p < 0.001); INC and VLNC did not differ. Cigarette choices did not differ from an even distribution (43% NNC, 25% INC, 32% VLNC), but choice for NNC or INC was associated with higher ratio of positive to negative reactions during the NNC and INC fixed dose sessions, respectively (p < 0.001).

CONCLUSIONS

Reducing nicotine content will likely lower the abuse liability of cigarettes for most young, low-frequency smokers. Additional work is needed to determine if compensatory smoking may lead to increased toxicant exposure, and if a subset of individuals choosing lower nicotine cigarettes may continue to smoke regardless of nicotine content.

Impact of nicotine reduction in cigarettes on smoking behavior and exposure: Are there differences by race/ethnicity, educational attainment, or gender?

BACKGROUND

Lowering nicotine in cigarettes may reduce smoking prevalences; however, it is not known whether an immediate or gradual reduction in nicotine is the optimal approach for all population groups.

OBJECTIVES

We examined whether the optimal approach to nicotine reduction depended on the education, gender, or race of people who smoke and whether the optimal approach differentially benefited people who smoke based on their education, gender, or race.

METHODS

Secondary analysis was conducted on a randomized clinical trial (N = 1250) comparing (1) immediate reduction from 15.5 to 0.4 mg of nicotine per gram of tobacco(mg/g);(2) gradual reduction to 0.4 mg/g;(3) control group with normal nicotine cigarettes(15.5 mg/g). Outcomes included cigarettes per day(CPD), carbon monoxide(CO), total nicotine equivalents(TNE), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol and its glucuronides(NNAL), phenanthrene tetraol(PheT), N-Acetyl-S-(2-cyanoethyl)-l-cysteine(CEMA). Data were analyzed as area under the curve(AUC).

RESULTS

Results were presented by education (High school[HS] or less n = 505, more than HS n = 745), gender (males n = 701, females n = 549), and race (Black participants n = 373,White participants n = 758). Regardless of education, gender, and race, CPD, CO, TNE, NNAL, PheT, and CEMA were lower in immediate versus gradual nicotine reduction. Comparing immediate versus the control, outcomes were lower for all subgroups; however, the magnitude of the effect for TNE varied by race. Specifically, geometric mean of the AUC of TNE in immediate versus gradual was 49 % lower in Black participants and 61 % lower in White participants (p-value = 0.047).

CONCLUSIONS

Immediately reducing nicotine in cigarettes has the potential to benefit people who smoke across lower and higher educational attainment, male and female gender, and Black and White race.

Which tobacco control policies do smokers support? Findings from the International Tobacco Control Four Country Smoking and Vaping Survey

As governments consider policy action to reduce smoking, a key factor in creating political will is the level of public support, particularly among smokers who are most affected by the policies. The goal of this paper is to assess and compare the level of support in Canada, the United States, England, and Australia for five smoking control policies: 1) banning menthol in cigarettes, 2) banning cigarette additives, 3) reducing nicotine in cigarettes to make them less addictive, 4) raising the minimum age to purchase cigarettes to 21 years and older, and 5) requiring pictorial warning labels on cigarette packs (examined in the US only). Data for these analyses come from 8165 daily cigarette smokers who responded to the 2016 International Tobacco Control Four Country Smoking and Vaping Survey. In all countries, the highest level of support was for raising the legal age for purchase to 21 years and older (62-70%) and reducing the nicotine content of cigarettes to make them less addictive (57-70%). Smokers who were less dependent on cigarettes and those expressing interest in quitting were more likely to support all policies. When asked how they would respond to a nicotine reduction policy, the most common response given was to try the non-nicotine cigarettes to see how they liked them (42-48%), with the next most common response being to quit smoking entirely (16-24%). The high level of support for these proposed policies among daily smokers provides important evidence for policymakers to counteract claims that such policies would be unpopular.

Regulatory approaches and implementation of minimally addictive combusted products

INTRODUCTION

A joint meeting was held by the World Health Organization (WHO) and the Convention Secretariat of the WHO Framework Convention on Tobacco Control to examine the potential effects of a regulatory policy to reduce nicotine in cigarettes to minimally addictive levels. This paper reviews the feasibility of and approaches to implementing a nicotine product standard.

METHODS

Prior WHO reports on this topic were consulted and a systematic review of the scientific literature was conducted. The paper was reviewed by the participants at the aforementioned meeting and their feedback was incorporated.

RESULTS

The nicotine dose most likely to consistently reduce smoking behavior and dependence is < 0.4 mg nicotine/g tobacco. An immediate rather than a gradual nicotine reduction approach appears to be more beneficial. Smokers are likely to seek nicotine from alternate sources (e.g., nicotine replacement therapies, e-cigarettes) or potentially, the illegal market. As such, the availability of alternative products, as well as strong policies against illegal markets, can potentially mitigate unintended consequences. An effective reduced nicotine regulation must be imbedded in a comprehensive and strong tobacco control program that includes public education and surveillance. Barriers and challenges to implementing a nicotine product standard exist, particularly in low-capacity countries.

CONCLUSION

Not all countries will have the capacity to implement a regulation to reduce nicotine in cigarettes (and preferably other combusted tobacco products) to minimally addictive levels. However, for the countries that choose to implement it, such a policy could potentially dramatically reduce the burden of tobacco use.

Subchronic effects of plant alkaloids on anxiety-like behavior in zebrafish

Zebrafish provide a valuable emerging complementary model for neurobehavioral research. They offer a powerful way to screen for the potential therapeutic effects of neuroactive drugs. A variety of behavioral tests for zebrafish have been developed and validated for assessing neurobehavioral function. The novel tank diving test is a straightforward, reproducible way of measuring anxiety-like behavior in zebrafish. When introduced into a novel tank, zebrafish normally dive to the bottom of the tank and then gradually explore the higher levels of the water column as time progresses. Buspirone is an effective anxiolytic drug in humans, which has been found, with acute administration, to reduce this anxiety-like response in zebrafish. The current study used the zebrafish model to evaluate the potential anxiolytic effects of alkaloids, commonly found in Solanaceae plants, with known neuropharmacology relevant to mood regulation. In line with previous findings, acute treatment with anxiolytic positive controls buspirone and the plant alkaloid nicotine reduced the anxiety-like diving response in the zebrafish novel tank diving test. Further, both buspirone and nicotine continued to produce anxiolytic-like effects in zebrafish after 5 days of exposure. In the same treatment paradigm, the effects of five other alkaloids-cotinine, anatabine, anabasine, harmane, and norharmane-were investigated. Cotinine, the major metabolite of nicotine, also caused anxiolytic-like effects, albeit at a dose higher than the effective dose of nicotine. Nicotine's anxiolytic-like effect was not shared by the other nicotinic alkaloids, anabasine and anatabine, or by the naturally present monoamine oxidase inhibitors harmane and norharmane. We conclude that nicotine uniquely induces anxiolytic-like effects after acute and subchronic treatment in zebrafish. The zebrafish model with the novel tank diving test could be a useful complement to rodent models for screening candidate compounds for anxiolytic effects in nonclinical studies.

A mixed effects model for analyzing area under the curve of longitudinally measured biomarkers with missing data

A simple approach for analyzing longitudinally measured biomarkers is to calculate summary measures such as the area under the curve (AUC) for each individual and then compare the mean AUC between treatment groups using methods such as t test. This two-step approach is difficult to implement when there are missing data since the AUC cannot be directly calculated for individuals with missing measurements. Simple methods for dealing with missing data include the complete case analysis and imputation. A recent study showed that the estimated mean AUC difference between treatment groups based on the linear mixed model (LMM), rather than on individually calculated AUCs by simple imputation, has negligible bias under random missing assumptions and only small bias when missing is not at random. However, this model assumes the outcome to be normally distributed, which is often violated in biomarker data. In this paper, we propose to use a LMM on log-transformed biomarkers, based on which statistical inference for the ratio, rather than difference, of AUC between treatment groups is provided. The proposed method can not only handle the potential baseline imbalance in a randomized trail but also circumvent the estimation of the nuisance variance parameters in the log-normal model. The proposed model is applied to a recently completed large randomized trial studying the effect of nicotine reduction on biomarker exposure of smokers.

Switching to Progressively Reduced Nicotine Content Cigarettes in Smokers With Low Socioeconomic Status: A Double-Blind Randomized Clinical Trial

INTRODUCTION

The Food and Drug Administration issued an advanced notice of proposed rulemaking for setting a product standard for nicotine levels in cigarettes, with an emphasis on minimally or non-addicting very low nicotine content (VLNC).

METHODS

A 33 week, two-arm, double-blind randomized trial conducted in Hershey, Pennsylvania, USA and Washington, DC, USA included adult daily cigarette smokers (≥5 cigarettes per day) with less than a college degree, and who had no plans to quit within the next six months. Participants were randomized to either reduced nicotine content (RNC) study cigarettes tapered every three weeks to a final VLNC (0.2 mg/cigarette) for six weeks or to usual nicotine content (UNC) study cigarettes (11.6 mg/cigarette). Outcomes included acceptability of study cigarettes measured by attrition (primary outcome), compliance, reduction in cigarette dependence and tobacco biomarkers, and post-intervention cessation.

RESULTS

The RNC (n = 122) versus UNC (n = 123) group had higher attrition (adjusted Hazard Ratio 3.4; 95% confidence interval [CI] 1.99 to 5.81). At the end of the intervention, cotinine levels were 50% lower in the RNC group (mean group difference -137 ng/mL; 95% CI -172, -102). The RNC group smoked fewer CPD (-4.1; 95% CI -6.44, -1.75) and had lower carbon monoxide levels (-4.0 ppm; 95% CI -7.7, -0.4). Forty seven percent (29/62) of the RNC group were biochemically-confirmed compliant with smoking VLNC cigarettes (mean cotinine = 8.9 ng/ml). At three month follow-up, only compliant VLNC smokers quit with an assisted quit attempt (N = 6/22, 27%).

CONCLUSIONS

This study supports a VLNC standard in cigarettes.

IMPLICATIONS

Differential dropout and noncompliance indicate some smokers had difficulty transitioning to cigarettes with reduced nicotine. These smokers will benefit from supplemental nicotine in medicinal or noncombustible tobacco products if a nicotine reduction standard is established. Other smokers successfully transitioned to very low nicotine content cigarettes exclusively and substantially reduced their exposure to nicotine.

Risk Perceptions of Low Nicotine Cigarettes and Alternative Nicotine Products across Priority Smoking Populations

BACKGROUND

As the U.S. Food and Drug Administration considers a low nicotine product standard for cigarettes, it is important to examine how people who smoke, especially individuals from priority populations disproportionately affected by smoking, perceive low nicotine content (LNC) cigarettes and their relative risk perceptions of alternative nicotine delivery system (ANDS) products, including e-cigarettes and snus, and medicinal nicotine.

METHODS

Data are from Wave 4 (2016-2017) of the adult Population Assessment of Tobacco Use and Health (PATH) Study. We examined respondents' absolute risk perceptions about nicotine, LNC cigarettes, ANDS products and medicinal nicotine; their relative risk perceptions of LNC cigarettes and ANDS products compared to conventional cigarettes; and their relative risk perceptions of medicinal nicotine compared to ANDS products.

RESULTS

The majority of respondents across priority smoking populations indicated snus, e-cigarettes, and LNC cigarettes were 'about the same' level of harmfulness or addictiveness as conventional cigarettes. The majority of respondents indicated e-cigarettes to be 'about the same' harmfulness as medicinal nicotine.

CONCLUSIONS

Our study indicates that adults who smoke cigarettes generally have misperceptions about the harms of nicotine and the relative risks of ANDS products and such misperceptions exist regardless of their racial/ethnic identity, sexual orientation, and gender identity.

Investigating tobacco withdrawal in response to reduced nicotine cigarettes among smokers with opioid use disorder and other vulnerabilities

Individuals with opioid use disorder (OUD) have high prevalence of smoking and poor cessation outcomes. Data suggest that smokers with OUD may experience heightened nicotine reinforcement and more severe tobacco withdrawal compared to smokers without OUD. The Food and Drug Administration is currently considering reducing the nicotine content of cigarettes to reduce smoking prevalence and smoking-related disease. It is critical to understand the effects of reduced nicotine content cigarettes (RNCCs) on tobacco withdrawal in this subgroup. In this secondary analysis, we investigated the ability of RNCCs to attenuate acute tobacco withdrawal and craving severity in smokers with OUD versus those without substance use disorders (SUDs). Smokers maintained on methadone or buprenorphine (opioid-maintained [OM]; n = 65) versus without other SUDs (i.e., non-SUD; n = 135) completed 5 laboratory sessions wherein they smoked their usual brand (UB) or a research cigarette varying in nicotine content (0.4, 2.4, 5.2, 15.8 mg/g of tobacco) under double-blind, acute abstinence conditions. Participants completed the Minnesota Tobacco Withdrawal Scale, including a desire to smoke (craving) item, before and every 15 min for 1 hr following smoking each cigarette. Tobacco withdrawal and craving did not differ significantly by OM status in response to UB or RNCCs. In addition to the Dose × Time interaction, greater depression and cigarette dependence consistently predicted withdrawal and craving (ps < .05). Across all cigarettes, tobacco withdrawal and craving did not significantly differ by OM status, suggesting that smokers receiving opioid agonist treatment may respond favorably to RNCCs. Additional studies with larger and more diverse samples are needed to address this question more definitively. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Trends in Manufacturer-Reported Nicotine Yields in Cigarettes Sold in the United States, 2013-2016

INTRODUCTION

A gradual reduction of cigarette nicotine content to nonaddictive levels has been proposed as an endgame strategy to accelerate declines in combustible tobacco smoking. We assessed manufacturer-reported nicotine yield in cigarettes sold in the United States from 2013 to 2016.

METHODS

We merged machine-measured nicotine yield in cigarette smoke and pack characteristics obtained from reports filed by tobacco manufacturers with the Federal Trade Commission for 2013-2016 with monthly Nielsen data on US cigarette sales. Manufacturer-reported, sales-weighted, average annual nicotine yield was assessed, as were nicotine yield sales trends by quartile: markedly low (0.10-0.60 mg/stick), low (0.61-0.80 mg/stick), moderate (0.81-0.90 mg/stick), and high (0.91-3.00 mg/stick). Trends in overall, menthol, and nonmenthol pack sales, by nicotine yield quartiles over the study period and by year, were determined by using Joinpoint regression.

RESULTS

During 2013-2016, average annual sales-weighted nicotine yield for all cigarettes increased from 0.903 mg/stick (95% CI, 0.882-0.925) in 2013 to 0.938 mg/stick (95% CI, 0.915-0.962) in 2016 (P < .05). For menthol cigarettes, yield increased from 0.943 mg/stick in 2013 (95% CI, 0.909-0.977) to 1.037 mg/stick in 2016 (95% CI, 0.993-1.081), increasing 0.2% each month (P < .05). Most pack sales occurred among high (41.5%) and low (30.7%) nicotine yield quartiles. Cigarette sales for the markedly low quartile decreased by an average of 0.4% each month during 2013-2016 (P < .05).

CONCLUSION

During 2013-2016, manufacturer-reported, sales-weighted nicotine yield in cigarettes increased, most notably for menthol cigarettes. Continued monitoring of nicotine yield and content in cigarettes can inform tobacco control strategies.

An Evaluation of Potential Unintended Consequences of a Nicotine Product Standard: A Focus on Drinking History and Outcomes

INTRODUCTION

A nicotine product standard reducing the nicotine content in cigarettes could improve public health by reducing smoking. This study evaluated the potential unintended consequences of a reduced nicotine product standard by examining its effects on (1) smoking behaviors based on drinking history; (2) drinking behavior; and (3) daily associations between smoking and drinking.

METHODS

Adults who smoke daily (n = 752) in the United States were randomly assigned to smoke very low nicotine content (VLNC) cigarettes versus normal nicotine content (NNC; control) cigarettes for 20 weeks. Linear mixed models determined if baseline drinking moderated the effects of VLNC versus NNC cigarettes on Week 20 smoking outcomes. Time-varying effect models estimated the daily association between smoking VLNC cigarettes and drinking outcomes.

RESULTS

Higher baseline alcohol use (vs no use or lower use) was associated with a smaller effect of VLNC on Week 20 urinary total nicotine equivalents (ps < .05). No additional moderation was supported (ps > .05). In the subsample who drank (n = 415), in the VLNC versus NNC condition, daily alcohol use was significantly reduced from Weeks 17 to 20 and odds of binge drinking were significantly reduced from Weeks 9 to 17. By Week 7, in the VLNC cigarette condition (n = 272), smoking no longer predicted alcohol use but remained associated with binge drinking.

CONCLUSIONS

We did not support negative unintended consequences of a nicotine product standard. Nicotine reduction in cigarettes generally affected smoking behavior for individuals who do not drink or drink light-to-moderate amounts in similar ways. Extended VLNC cigarette use may improve public health by reducing drinking behavior.

IMPLICATIONS

There was no evidence that a VLNC product standard would result in unintended consequences based on drinking history or when considering alcohol outcomes. Specifically, we found that a very low nicotine standard in cigarettes generally reduces smoking outcomes for those who do not drink and those who drink light-to-moderate amounts. Furthermore, an added public health benefit of a very low nicotine standard for cigarettes could be a reduction in alcohol use and binge drinking over time. Finally, smoking VLNC cigarettes may result in a decoupling of the daily associations between smoking and drinking.

Tobacco harm reduction: Past history, current controversies and a proposed approach for the future

Tobacco harm reduction remains a controversial topic in tobacco control. Tobacco harm reduction involves providing tobacco users who are unwilling or unable to quit using nicotine products with less harmful nicotine-containing products for continued use. The skepticism towards harm reduction is based in part on the experience with low-yield tar/nicotine cigarettes, which were presumed to be associated with lower health risks than higher yield cigarettes and marketed as such by cigarette manufacturers. Only later did the field learn that these cigarettes were a deceptive way for cigarette manufacturers to allay the health concerns over cigarette smoking. Since this experience, there has been a proliferation of tobacco products that might potentially serve as a means to reduce tobacco harm. Some members of the tobacco control community believe that these products have great potential to reduce mortality and morbidity among smokers who completely switch to them. Others believe that we will be addicting another generation to tobacco products. This paper reviews the past history, the current tobacco landscape and controversies, and an approach that might rapidly reduce the yearly half-million deaths associated with cigarette smoking in the U.S.

Facilitating smoking cessation using reduced nicotine cigarettes: Intervention development and RCT study design

Smoking cigarettes with substantially lower nicotine than conventional cigarettes prior to a quit attempt may reduce the reinforcing effects of smoking, which could facilitate smoking cessation through extinction learning. This paper describes the development of a smoking cessation intervention designed to optimize extinction processes using reduced nicotine cigarettes, as well as the design and methods for an ongoing randomized controlled trial (RCT) to evaluate this intervention. Qualitative methods and pilot testing were conducted to develop the novel facilitated extinction (FE) intervention, with a key focus on maximizing opportunities for extinction learning during a five-week pre-quit period. The primary aims of the RCT are to test the effects of the FE intervention versus a standard (cognitive-behavioral) intervention, while also comparing two nicotine reduction schedules for providing very low nicotine content (VLNC) cigarettes. The efficacy of the intervention is currently being evaluated with treatment-seeking smokers (n = 208) randomly assigned to one of four conditions crossing FE versus standard intervention with immediate versus gradual transition to VLNC cigarettes.

Reducing tobacco use among women of childbearing age: Contributions of tobacco regulatory science and tobacco control

Tobacco use has unique, adverse health consequences for reproductive-aged women, particularly should these women become pregnant. Thus, successful efforts to reduce tobacco use among this population have strong potential to improve public health and reduce health disparities. The present review examines contributions to reducing tobacco use among women of childbearing age spanning the domains of tobacco regulatory science and tobacco control from the passage of the Family Smoking Prevention and Tobacco Control Act in 2009 through September 2019. In the domain of tobacco regulatory science, such efforts include research conducted by various National Institutes of Health/Food and Drug Administration (FDA)-supported Tobacco Centers of Regulatory Science, epidemiological surveillance studies, as well as studies examining the potential impact of tobacco regulatory policies currently under consideration by the FDA (e.g., reduced nicotine content cigarettes, health warning labels). Tobacco control efforts within this same 10-year timeframe include developments in pharmacological and psychosocial approaches to promoting tobacco cessation, mHealth interventions, and tobacco control policy. Emerging issues pertinent to ongoing efforts to reduce tobacco use within the domains of both tobacco regulatory science and tobacco control are also reviewed, including e-cigarettes, comorbid health conditions, course of tobacco and other drugs of abuse, and obstacles to the dissemination and implementation of evidence-based treatment and policy. Although the past decade has seen numerous important contributions to reducing tobacco use among reproductive-aged women within both domains, existing obstacles must be surmounted to continue reducing tobacco use and protecting health among this population. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Changes in Cigarette Consumption With Reduced Nicotine Content Cigarettes Among Smokers With Psychiatric Conditions or Socioeconomic Disadvantage: 3 Randomized Clinical Trials

IMPORTANCE

This study is part of a programmatic effort evaluating the effects of reducing nicotine content of cigarettes to minimally addictive levels.

OBJECTIVE

To examine whether very low-nicotine-content (VLNC) cigarettes decrease smoking rates and dependence severity among smokers with psychiatric disorders or socioeconomic disadvantage.

DESIGN, SETTING, AND PARTICIPANTS

These 3 randomized clinical trials were performed at the University of Vermont, Brown University, and Johns Hopkins University between October 2016 and September 2019. Participants received 12 weeks of exposure to study cigarettes with nicotine content ranging from levels representative of commercial cigarettes (15.8 mg nicotine/g tobacco) to less than a hypothesized addiction threshold (2.4 mg/g and 0.4 mg/g). Daily smokers from 3 at-risk populations participated: individuals with affective disorders, exemplifying smokers with mental illness; individuals with opioid use disorder, exemplifying smokers with substance use disorders; and women with high school educations or less, exemplifying smokers with socioeconomic disadvantage. Data were analyzed from September 2019 to July 2020.

INTERVENTIONS

Random assignment to 1 of 3 study cigarettes provided weekly at no cost for 12 weeks.

MAIN OUTCOMES AND MEASURES

The primary outcome was between-group differences in mean total cigarettes smoked daily (CPD) during week 12; secondary outcomes included CPD for study and nonstudy cigarettes and dependence severity across weeks analyzed using analysis of covariance, random coefficients growth modeling, or repeated measures analysis of variance.

RESULTS

A total of 775 participants were included (mean [SD] age, 35.59 [11.05] years; 551 [71.10%] women [owing to 1 population being exclusively women]); participants smoked a mean (SD) of 17.79 (9.18) CPD at study intake. A total of 286 participants were randomized to 0.4 mg/g, 235 participants were randomized to 2.4 mg/g, and 254 participants were randomized to 15.8 mg/g. Participants randomized to VLNC cigarettes had decreased mean [SEM] total CPD during week 12 across populations (Cohen d = 0.61; P < .001). At week 12, mean (SEM) CPD decreased to 17.96 (0.98) CPD in the 0.4 mg/g group and to 19.53 (1.07) CPD in the 2.4 mg/g group, both of which were significantly different from the 15.8 mg/g group (25.08 [1.08] CPD at week 12) but not each other (0.4 mg/g adjusted mean difference: -7.54 [95%CI, -9.51 to -5.57]; 2.4 mg/g adjusted mean difference: -5.34 [95% CI, 7.41 to -3.26]). Several secondary outcomes differed across populations randomized to VLNCs, including mean total CPD across weeks, with linear trends lower in participants receiving 0.4 mg/g (-0.28 [95%CI, -0.39 to -0.18]; P < .001) and 2.4 mg/g (-0.13 [95%CI, -0.25 to -0.01]; P < .001) doses compared with those receiving the 15.8 mg/g dose (0.30 [95% CI, 0.19 to 0.41]). Fagerström Test of Nicotine Dependence mean total scores were significantly lower in participants who received VLNCs (Cohen d = 0.12; P < .001), with those who received the 0.4 mg/g dose (mean [SD] score, 3.99 [0.06]; P < .001 vs 15.8 mg/g) or 2.4 mg/g dose (mean [SD] score, 4.07 [0.06]; P = .01 vs 15.8 mg/g) differing from those who received the 15.8 mg/g dose (mean [SD] score, 4.31 [0.06]) but not from each other.

CONCLUSIONS AND RELEVANCE

These findings demonstrate that decreasing the nicotine content of cigarettes to very low levels reduced smoking rate and nicotine-dependence severity in these high-risk populations, effects that may facilitate successful cessation.

TRIAL REGISTRATION

ClinicalTrials.gov Identifiers: NCT02232737, NCT02250664, NCT02250534.

Comparison between Gradual Reduced Nicotine Content and Usual Nicotine Content Groups on Subjective Cigarette Ratings in a Randomized Double-Blind Trial

In 2018, the United States Food and Drug Administration (FDA) issued an advanced notice of proposed rulemaking to reduce nicotine in tobacco products to produce a minimally addictive or nonaddictive effect, but there was a research gap in the subjective responses of reduced-nicotine-content cigarettes. We compared the responses of the modified cigarette evaluation questionnaire (mCEQ) and cigarette-liking scale (CLS) between the gradually reduced nicotine content (RNC) group and the usual nicotine content (UNC) group. Linear mixed-effects models for repeated measures were used to analyze and compare the change over time for the mCEQ and CLS across the two treatment groups (RNC and UNC). We found that the change over time for the mCEQ and CLS was significant between the RNC and the UNC treatment groups at the beginning of visit 6 with 1.4 mg nicotine/cigarette. At visits 8 and 9, the RNC group reported significantly lower satisfaction scores compared to UNC. Subscale analysis showed that smoking satisfaction decreased in RNC while other measures, such as cigarette enjoyment, did not change. Understanding the impact of nicotine reduction on cigarette subjective responses through evaluation and liking scales would provide valuable information to the FDA on nicotine reduction policies for cigarettes.

Comparison of smoking cessation rates of Quitline users in Korea between smokers of ultra-low nicotine yield cigarettes and other types of cigarette: a prospective study

AIMS

It is not known whether the machine-smoked nicotine yield of usual brand of cigarette smoked is associated with the chances of success of quit attempts. This study aimed to assess this association.

DESIGN

Prospective study.

SETTING

Republic of Korea.

PARTICIPANTS

A total of 16 808 male smokers registered for the Quitline between 7 April 2006 and 31 December 2013. Of these, 13 176 participants who were > 19 years of age and provided data on their demographic characteristics, smoking-related behaviors, nicotine dependence, tobacco brands used and self-efficacy were included in this study.

MEASUREMENTS

Machine-smoked nicotine yield was based on information provided by tobacco companies on cigarette packages that smokers reported as their usual brand. Ultra-low nicotine yield was defined as ≤ 0.1 mg machine-smoked nicotine yield per cigarette, whereas higher nicotine yield was defined as > 0.1 mg machine-smoked nicotine yield. Participant personal information and self-reported continuous abstinence at 1-month, 6-month and 1-year follow-up were recorded in electronic databases.

FINDINGS

Continuous abstinence rates in the ultra-low nicotine yield versus higher nicotine yield groups were, respectively, 40.7 versus 34.6% at 1 month [odds ratio (OR) = 1.22, 95% confidence interval (CI) = 1.12-1.33], 22.7 versus 18.8% at 6 months (OR = 1.20, 95% CI = 1.08-1.32) and 19.5 versus 16.6% (OR = 1.19, 95% CI = 1.10-1.29) at 1 year. The association between ultra-low nicotine yield cigarette smoking and successful quitting was stronger among the smokers with higher cigarette dependence.

CONCLUSIONS

Male smokers who use the Korean Quitline are more likely to quit successfully if they smoke ultra-low nicotine yield cigarettes than if they smoke higher nicotine yield cigarettes.

Pharmacokinetic Profile of Spectrum Reduced Nicotine Cigarettes

INTRODUCTION

Spectrum research cigarettes have been developed with varying nicotine content for use in studies evaluating the effects of a regulatory policy reducing the permissible nicotine content in cigarettes. This study aimed to characterize the nicotine pharmacokinetic profile of Spectrum cigarettes.

METHODS

Twelve daily smokers attended four sessions and had blood nicotine, exhaled carbon monoxide, and subjective effects measured before and after smoking either a single cigarette of their preferred brand or high (10.9 mg/cigarette), medium (3.2 mg/cigarette), or low (0.2 mg/cigarette) nicotine content Spectrum research cigarettes, in a double-blind design with order counterbalanced.

RESULTS

The boost in blood nicotine concentration was dose-dependent, with a boost of 0.3, 3.9, and 17.3 ng/mL for low-, medium-, and high-nicotine content Spectrum cigarettes. The high dose Spectrum had a similar nicotine boost to the "preferred brand" cigarettes (19 ng/mL). Subjects took longer puffs on the low nicotine cigarettes, but smoked these cigarettes faster than other cigarette types. High nicotine Spectrum cigarettes reduced the urge to smoke more than other cigarette types.

CONCLUSIONS

This study shows that Spectrum research cigarettes produce blood nicotine absorption in a dose-dependent manner, and therefore, are appropriate for use in studies of nicotine reduction in cigarettes.

IMPLICATIONS

This is the first study to determine the pharmacokinetic profile of Spectrum reduced nicotine content research cigarettes following an overnight abstinence. These data could provide evidence to regulatory agencies about the effects of reduced nicotine cigarettes when considering regulations on tobacco reduction.

More than Smoke and Patches: The Quest for Pharmacotherapies to Treat Tobacco Use Disorder

Tobacco use is a persistent public health issue. It kills up to half its users and is the cause of nearly 90% of all lung cancers. The main psychoactive component of tobacco is nicotine, primarily responsible for its abuse-related effects. Accordingly, most pharmacotherapies for smoking cessation target nicotinic acetylcholine receptors (nAChRs), nicotine's major site of action in the brain. The goal of the current review is twofold: first, to provide a brief overview of the most commonly used behavioral procedures for evaluating smoking cessation pharmacotherapies and an introduction to pharmacokinetic and pharmacodynamic properties of nicotine important for consideration in the development of new pharmacotherapies; and second, to discuss current and potential future pharmacological interventions aimed at decreasing tobacco use. Attention will focus on the potential for allosteric modulators of nAChRs to offer an improvement over currently approved pharmacotherapies. Additionally, given increasing public concern for the potential health consequences of using electronic nicotine delivery systems, which allow users to inhale aerosolized solutions as an alternative to smoking tobacco, an effort will be made throughout this review to address the implications of this relatively new form of nicotine delivery, specifically as it relates to smoking cessation. SIGNIFICANCE STATEMENT: Despite decades of research that have vastly improved our understanding of nicotine and its effects on the body, only a handful of pharmacotherapies have been successfully developed for use in smoking cessation. Thus, investigation of alternative pharmacological strategies for treating tobacco use disorder remains active; allosteric modulators of nicotinic acetylcholine receptors represent one class of compounds currently under development for this purpose.

Effects on time to lapse of switching menthol smokers to non-menthol cigarettes prior to a cessation attempt: a pilot study

INTRODUCTION

Menthol smokers (particularly African-Americans) have lower cessation success rates than non-menthol smokers. With bans being considered on characterising menthol flavour in cigarettes, data are needed regarding how switching to non-menthol cigarettes impacts cessation measures.

METHODS

In this randomised pilot study, African-American menthol cigarette smokers interested in quitting smoking either continued smoking menthol cigarettes (n=60) or switched to non-menthol cigarettes (n=62) for a 1-month period prior to a cessation attempt. The primary endpoint was time to smoking lapse (ie, time from quitting until any smoking). Additional endpoints included time to smoking relapse (ie, number of days from quitting until the first of seven consecutive smoking days) and difference between groups in subjective measures.

RESULTS

After attempting to quit, the non-menthol cigarette group had indications of delayed time to lapse (HR 0.82; 95% CI 0.55 to 1.22; p=0.33) and time to relapse (HR 0.67; 95% CI 0.42 to 1.06; p=0.09), although these were not statistically significant. Post hoc analyses suggest that observed differences were largely due to a smaller proportion of participants in the non-menthol group relapsing within the first day of quitting (21% vs 40%; p=0.05). Values of other measures assessed postcessation were largely similar between groups.

CONCLUSIONS

These data suggest that among African-American smokers, a menthol cigarette ban would not undermine short-term cessation measures and may result in some benefits. Future research is needed to assess longer term cessation rates and to identify interventions to maximise cessation success in the event of a menthol ban.

TRIAL REGISTRATION NUMBER

NCT02342327.

Nicotine reduction does not alter essential value of nicotine or reduce cue-induced reinstatement of nicotine seeking

Reduction of nicotine content in tobacco products is a regulatory control strategy intended to decrease smoking dependence, and is hypothesized to produce gradual reductions of nicotine intake. Rats were initially trained to self-administer 0.06 mg/kg/infusion nicotine (Phase 1), which was followed by a threshold procedure to determine nicotine demand via a behavioral economics (BE) paradigm (Phase 2). Rats then either self-administered the training dose (high dose group), or were switched to a low dose of nicotine (0.001 mg/kg/infusion; low dose group) in Phase 3. Both groups then underwent a second threshold procedure and demand curves were re-determined (Phase 4). In Phase 5, responding for nicotine was extinguished over the course of 21 sessions. Cue-induced reinstatement was then evaluated (Phase 6). Rats in the low dose group maintained a steady amount of infusions, and thus, did not compensate for nicotine reduction. Rats in the low dose group also showed similar demand elasticity and nicotine seeking (Phase 6) compared to the high dose group, indicating that nicotine reduction did not decrease nicotine demand or seeking. Further, both groups displayed resistance to extinction, indicating that nicotine reduction did not facilitate extinction learning. These results suggest that although compensation of intake does not occur, decreasing the dose of nicotine does not alter nicotine reinforcement value or relapse vulnerability. Further, these results indicate persistence of nicotine-motivated behavior after self-administration of a low nicotine dose. Translationally, these results suggest that alternative strategies may be needed to achieve positive smoking cessation outcomes.

Reducing the relative value of cigarettes: Considerations for nicotine and non-nicotine factors

Despite notable progress in recent decades, cigarette smoke persists as a leading cause of premature death and preventable disease. To weaken the link between nicotine reinforcement and the toxicity associated with combusted tobacco, the United States Food and Drug Administration is considering a product standard targeting cigarette nicotine content. In this review, we summarize research assessing the potential impacts of reducing nicotine in cigarettes. Evidence to date suggests cigarette smoking, toxicant exposure and dependence would decline following substantial reductions in nicotine content. However, reduced nicotine content may not eliminate smoking entirely. Regulatory efforts that shape the nicotine and tobacco marketplace should consider that non-nicotine reinforcing factors and decision-making biases can contribute to the value of smoking. The impact of reducing nicotine in cigarettes will likely depend on the alternative nicotine products available to current smokers. This article is part of the special issue on 'Contemporary Advances in Nicotine Neuropharmacology'.

The Role of Compensation in Nicotine Reduction

The available research on switching from normal nicotine to very low nicotine content cigarettes shows minimal evidence of compensatory smoking. Mathematical estimations suggest that substantial compensation after switching to very low nicotine cigarettes would be impossible. It is likely that smokers who are unable to tolerate the extent of proposed nicotine reduction would switch to other sources of nicotine, rather than try to compensate by smoking more very low nicotine content cigarettes more intensely.