Acceptability of SPECTRUM Research Cigarettes among Participants in Trials of Reduced Nicotine Content Cigarettes

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.

Blood Nicotine Predicts the Behavioral Economic Abuse Liability of Reduced-Nicotine Cigarettes

BACKGROUND

Cigarette smoking continues to be a major health concern and remains the leading preventable cause of death in the US. Recent efforts have been made to determine the potential health and policy benefits of reducing nicotine in combustible cigarettes. The degree to which changes in blood nicotine relate to measures of the abuse liability of reduced-nicotine cigarettes is unknown. The current study examined the relation between blood nicotine and behavioral economic demand measures of cigarettes differing in nicotine content.

METHODS

Using a within-subject design, participants smoked a single cigarette during each experimental session. Cigarettes included the participant's usual-brand cigarette and SPECTRUM investigational cigarette differing in nicotine level (mg of nicotine to g of tobacco; 15.8 mg/g, 5.2 mg/g, 2.4 mg/g, 1.3 mg/g, and 0.4 mg/g). During each session, blood was collected at multiple timepoints and behavioral economic demand was assessed. Nonlinear mixed-effects models were used to estimate differences in derived intensity (Q0) and change in elasticity (α).

RESULTS

Measures of blood nicotine decreased in an orderly fashion related to nicotine level and significantly predicted change in elasticity (α), but not derived intensity. No differences in demand parameters between the usual brand and 15.8mg/g cigarettes were observed. However, α was significantly higher (lower valuation) for 0.4mg/g than 15.8mg/g cigarettes.

CONCLUSIONS

The lowest nicotine level (0.4mg/g) corresponded with the lowest abuse liability (α) compared to the full-strength control (15.8mg/g), with the 1.3mg/g level also resulting in low abuse liability.

IMPLICATIONS

This is the first study examining the relative contributions of nicotine content in cigarettes and blood nicotine levels on the behavioral economic demand abuse liability of cigarettes ranging in nicotine content. Our results suggest blood nicotine and nicotine content both predict behavioral economic demand abuse liability. In addition, our results suggest a nicotine content of 1.3mg/g or lower may be effective at reducing cigarette uptake among first-time (naïve) smokers. Our results largely conform to previous findings suggesting a very low nicotine content cigarette maintains lower abuse liability than full-strength cigarettes.

Effects of Reduced-Nicotine Cigarettes Across Regulatory Environments in the Experimental Tobacco Marketplace: A Randomized Trial

INTRODUCTION

Cigarette smoking remains the leading preventable cause of death in the United States. Recent efforts have explored the potential health and policy benefits of reducing nicotine, an addictive component, in combustible cigarettes. To date, an experimental, prospective analysis directly comparing the effects of varying regulatory environments on purchases of multiple products has yet to be conducted. The present study compared real purchasing of conventional cigarettes, reduced-nicotine cigarettes, and a variety of other nicotine and tobacco products across a range of regulatory environments.

METHODS

Participants were assigned to one of five groups, each associated with a different nicotine level (mg of nicotine to g of tobacco) in SPECTRUM investigational cigarettes (15.8, 5.2, 2.4, 1.3, and 0.4 mg/g). Across sessions, participants made real purchases for nicotine/tobacco products in an Experimental Tobacco Marketplace. Each session corresponded with a distinct regulatory environment wherein different nicotine/tobacco products were available for purchase.

RESULTS

Our results suggest that the primary drivers of cigarette and nicotine purchasing are regulatory environment and the presence/absence of alternative nicotine and tobacco products. Perhaps surprisingly, nicotine level does not appear to be such a driver of purchasing behavior under these experimental conditions. Investigational cigarette purchasing is lowest when other preferred combustible products are available and highest when investigational cigarettes are the only combustible product available for purchase.

CONCLUSIONS

If a reduced-nicotine policy is implemented, great care should be taken in determining and making available less-harmful nicotine/tobacco products as the availability of preferred combustible products may result in undesirable levels of purchasing.

IMPLICATIONS

This is the first experimental study investigating different potential regulatory effects related to a reduced-nicotine policy by examining purchasing across a range of nicotine/tobacco products. Our results suggest the presence of affordable, highly preferred combustible products is likely to maintain tobacco purchasing at undesirable levels. To promote switching to less-harmful products, affordable alternate nicotine and tobacco products should be readily available. Finally, our results suggest that the availability of noncigarette products, not cigarette nicotine level, will most likely affect purchasing of reduced-nicotine cigarettes.

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.

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.

Nicotine Reduction in Cigarettes: Literature Review and Gap Analysis

BACKGROUND

The US Food and Drug Administration (FDA) is considering reducing nicotine levels in cigarettes to "minimally or non-addictive levels." However, important research gaps remain, and the FDA must determine when the available research is sufficient to support moving forward.

METHODS

The authors conducted a systematic review of research articles in PubMed relating to nicotine reduction. Building on a review of risk assessment best practices, the authors also developed a risk assessment framework for tobacco regulation and used it to guide a gap analysis of nicotine reduction research.

RESULTS

The final sample consisted of 78 articles. The majority examined either nicotine dependence on very low nicotine cigarettes (VLNCs) or markers of potential health effects of using VLNCs. One-third of the identified articles reported results from four large randomized controlled trials (RCTs). While these studies report promising results and suggest that a nicotine reduction rule would be a powerful tool to reduce cigarette smoking, our gap analysis suggests that there is a need for studies that better reflect the use and availability of a wide range of tobacco/nicotine products and the potential for dual- or multi-product use.

CONCLUSION

The current body of research on nicotine reduction is weighted towards RCTs, which is appropriate for a policy that has not yet been implemented anywhere in the world. The FDA must consider a wide range of factors that may impact a product standard's public health impact, including those difficult to assess in RCTs, such as a nicotine reduction rule's impact on smoking initiation and relapse.

IMPLICATIONS

This systematic review presents a gap analysis based on a risk assessment framework to help identify remaining research priorities to inform FDA's potential product standard to reduce nicotine levels in cigarettes. Quickly addressing those gaps would support the FDA's effort to develop a nicotine reduction product standard that will be effective and withstand legal challenges.

Measures of dependence in menthol and nonmenthol smokers - A comprehensive narrative review

Introduction. More than a decade ago, concerns were raised that menthol in cigarettes might enhance addiction to smoking. This article provides a comprehensive review of published studies examining cigarette dependence among menthol and nonmenthol smokers. The purpose of the review is to evaluate the scientific evidence to determine if menthol increases cigarette dependence. Materials and Methods. The published literature was searched in 2019 for studies that provide evidence on cigarette dependence among menthol compared to nonmenthol smokers. Included in this review are published studies that compare menthol and nonmenthol smokers based on widely accepted and validated measures of dependence, or other established predictors of dependence (age of smoking initiation [first cigarette]/age of progression [regular/daily smoking]) and indicators of dependence (smoking frequency, cigarettes smoked per day, time to first cigarette after waking, night waking to smoke, smoking duration). Results and Conclusion. Based on a review of the available studies, including those with adjusted results and large representative samples, reliable and consistent empirical evidence supports a conclusion that menthol smokers are not more dependent than nonmenthol smokers and thus menthol in cigarettes does not increase dependence.

Effect of Cigarette Rod Length on Smokers Switching to SPECTRUM Cigarettes

Objectives: Cigarettes vary in rod length but are generally thought of as a constant unit. In this study, we evaluated whether the rod length of participants' usual brand cigarettes affected their perceptions and smoking habits when switching to SPECTRUMs. Methods: Data were analyzed for 341 participants smoking their own brand cigarettes for one week and after switching to normal nicotine content (11.6 mg) SPECTRUMs for 2 weeks. Changes in perceptions of cigarette attributes and biomarkers of smoke exposure were evaluated using linear mixed models among 3 groups: usual length short (ULS, 72 mm); medium/king (ULM, ~84 mm); and long (ULL ≥ 100 mm). Results: Among the 3 cigarette length groups, only ULL smokers' rated SPECTRUMs significantly less strong, harder to draw, lower in taste, and lower in enjoyment (p < .03) compared to usual brand. Among all groups, satisfaction was significantly lower for SPECTRUMs (p < .02). Cigarettes per day (CPD) increased significantly more for ULL (+4.75 CPD) as compared to ULM (+1.38 CPD) (p < .001). When switching to SPECTRUMs, cotinine-per-cigarette decreased among all groups, and exhaled carbon monoxide increased significantly in ULL and ULM smokers (p < .001). Conclusion: People who smoked long cigarettes had the largest changes in perceptions and use when switching to SPECTRUM research cigarettes.

Estimation of compliance with exclusive smoking of very low nicotine content cigarettes using plasma cotinine

Regulations requiring a reduction of the nicotine content in cigarettes to minimally addictive levels could significantly reduce the public health impact of cigarette smoking. Clinical trials evaluating this strategy are ongoing and methods have been developed to use nicotine biomarkers to estimate compliance with use of very low nicotine content cigarettes (VLNCs). To date, these methods have not considered the potential contribution of nicotine absorption from environmental tobacco smoke (ETS) among research participants. This study used data from 100 randomly selected study completers in ongoing clinical trials of VLNCs (50 randomized to Usual Nicotine Content Cigarettes (UNCs) and 50 to VLNCs) to assess the use of plasma cotinine to estimate compliance. Plasma cotinine and smoking behavior were recorded at baseline after 2 weeks smoking UNC cigarettes, and then after 18 weeks of either continuing smoking UNCs or reducing the nicotine content such that the last 6 weeks comprised smoking VLNCs. Plasma cotinine remained stable (267 ng/ml) in the UNC group but reduced to 93 ng/ml in the VLNC group (p < 0.01). Compliance with smoking VLNCs was first estimated by comparing the cotinine per cigarette on VLNCs with UNCs after allowing for potential compensatory smoking. We found that 29 (58%) of the VLNC group were compliant. Adjusting for potential ETS exposure estimated 32 (64%) to be compliant. This latter group (n = 32) had a mean plasma cotinine on VLNCs of 7 ng/ml (range = 3-16.4 ng/ml). Adjusting for potential ETS exposure may improve identification of participants who plausibly complied with exclusive VLNC use.