The efficacy and acceptability of pharmacological monotherapies and e-cigarette on smoking cessation: a systemic review and network meta-analysis.

Background and aims: Several pharmacological interventions, such as nicotine replacement therapy (NRT), varenicline, and bupropion, have been approved for clinical use of smoking cessation. E-cigarettes (EC) are increasingly explored by many RCTs for their potentiality in smoking cessation. In addition, some RCTs are attempting to explore new drugs for smoking cessation, such as cytisine. This network meta-analysis (NMA) aims to investigate how these drugs and e-cigarettes compare regarding their efficacy and acceptability. Materials and methods: This systematic review and NMA searched all clinical studies on smoking cessation using pharmacological monotherapies or e-cigarettes published from January 2011 to May 2022 using MEDLINE, COCHRANE Library, and PsychINFO databases. NRTs were divided into transdermal (TDN) and oronasal nicotine (ONN) by administrative routes, thus 7 network nodes were set up for direct and indirect comparison. Two different indicators measured the efficacy: prevalent and continuous smoking abstinence. The drop-out rates measured the acceptability. Results: The final 40 clinical studies included in this study comprised 77 study cohorts and 25,889 participants. Varenicline is more effective intervention to assist in smoking cessation during 16-32 weeks follow-up, and is very likely to prompt dropout. Cytisine shows more effectiveness in continuous smoking cessation but may also lead to dropout. E-cigarettes and oronasal nicotine are more effective than no treatment in encouraging prevalent abstinence, but least likely to prompt dropout. Finally, transdermal nicotine delivery is more effective than no treatment in continuous abstinence, with neither significant effect on prevalent abstinence nor dropout rate. Conclusion: This review suggested and agreed that Varenicline, Cytisine and transdermal nicotine delivery, as smoking cessation intervention, have advantages and disadvantages. However, we had to have reservations about e-cigarettes as a way to quit smoking in adolescents.

The trajectory of smoking cessation after treatment and its related factors in Taiwan.

Smoking has multiple negative effects on health; therefore, the Taiwanese government provides smoking cessation clinics to smokers. This study aimed to explore the trajectory of smoking cessation after smokers received treatment and the variables related to different trajectories. A retrospective longitudinal study was conducted, in which 735 adult smokers who received smoking cessation medications were recruited. The participants' demographic characteristics, chronic diseases, smoking characteristics, and cigarette dependence were collected from chart review. The amount of smoking was collected at baseline, and at 1 week, 1 month, 3 months, and 6 months after treatment. The Proc Traj procedure for group-based modeling and multinomial logistic regression were used for statistical analysis. Three trajectories were identified: early quitters (28.03%), late quitters (11.43%) and reducers (60.54%). Compared with early quitters, reducers were younger and had a higher probability of severe cigarette dependence. Compared with early quitters, late quitters had a higher number of taking smoking cessation medications. The findings revealed that approximately 60% of participants who received smoking cessation treatment could not completely quit smoking, and that age, number of medications taken, and cigarette dependence were significant predictors of different trajectories.

Feasibility of restricting e-cigarettes to prescription only for smoking cessation.

E-cigarette use among youth in Canada has risen to epidemic proportions. E-cigarettes are also moderately useful smoking cessations aids. Restricting e-cigarettes to prescription only smoking cessation aids could help limit youth's access to them while keeping them available as therapies for patients who smoke conventional cigarettes. In Canada, drugs or devices must be approved by regulatory bodies such as Health Canada in order to become licensed prescription medications. A similar situation is underway in Australia, where e-cigarettes have been restricted to prescription only. This commentary explores the feasibility of a similar regulation for e-cigarettes in Canada as prescription smoking cessation aids.

Investigating disparities in smoking cessation treatment for veterans with multiple sclerosis: A national analysis.

BACKGROUND AND AIMS: Smoking is a risk factor for multiple sclerosis (MS) development, symptom burden, decreased medication efficacy, and increased disease-related mortality. Veterans with MS (VwMS) smoke at critically high rates; however, treatment rates and possible disparities are unknown. To promote equitable treatment, we aim to investigate smoking cessation prescription practices for VwMS across social determinant factors. METHODS: We extracted data from the national Veterans Health Administration electronic health records between October 1, 2017, and September 30, 2018. To derive marginal estimates of the association of MS with receipt of smoking-cessation pharmacotherapy, we used propensity score matching through the extreme gradient boosting machine learning model. VwMS who smoke were matched with veterans without MS who smoke on factors including age, race, depression, and healthcare visits. To assess the marginal association of MS with different cessation treatments, we used logistic regression and conducted stratified analyses by sex, race, and ethnicity. RESULTS: The matched sample achieved a good balance across most covariates, compared to the pre-match sample. VwMS (n = 3320) had decreased odds of receiving prescriptions for nicotine patches ([Odds Ratio]OR = 0.86, p < .01), non-patch nicotine replacement therapy (NRT; OR = 0.81, p < .001), and standard practice dual NRT (OR = 0.77, p < .01), compared to matches without MS (n = 13,280). Men with MS had lower odds of receiving prescriptions for nicotine patches (OR = 0.88, p = .05), non-patch NRT (OR = 0.77, p < .001), and dual NRT (OR = 0.72, p < .001). Similarly, Black VwMS had lower odds of receiving prescriptions for patches (OR = 0.62, p < .001), non-patch NRT (OR = 0.75, p < .05), and dual NRT (OR = 0.52, p < .01). The odds of receiving prescriptions for bupropion or varenicline did not differ between VwMS and matches without MS. CONCLUSION: VwMS received significantly less smoking cessation treatment, compared to matched controls without MS, showing a critical gap in health services as VwMS are not receiving dual NRT as the standard of care. Prescription rates were especially lower for male and Black VwMS, suggesting that under-represented demographic groups outside of the white female category, most often considered as the "traditional MS" group, could be under-treated regarding smoking cessation support. This foundational work will help inform future work to promote equitable treatment and implementation of cessation interventions for people living with MS.

Interventions for smoking cessation in hospitalised patients.

BACKGROUND: In 2020, 32.6% of the world's population used tobacco. Smoking contributes to many illnesses that require hospitalisation. A hospital admission may prompt a quit attempt. Initiating smoking cessation treatment, such as pharmacotherapy and/or counselling, in hospitals may be an effective preventive health strategy. Pharmacotherapies work to reduce withdrawal/craving and counselling provides behavioural skills for quitting smoking. This review updates the evidence on interventions for smoking cessation in hospitalised patients, to understand the most effective smoking cessation treatment methods for hospitalised smokers. OBJECTIVES: To assess the effects of any type of smoking cessation programme for patients admitted to an acute care hospital. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search date was 7 September 2022. SELECTION CRITERIA: We included randomised and quasi-randomised studies of behavioural, pharmacological or multicomponent interventions to help patients admitted to hospital quit. Interventions had to start in the hospital (including at discharge), and people had to have smoked within the last month. We excluded studies in psychiatric, substance and rehabilitation centres, as well as studies that did not measure abstinence at six months or longer. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcome was abstinence from smoking assessed at least six months after discharge or the start of the intervention. We used the most rigorous definition of abstinence, preferring biochemically-validated rates where reported. We used GRADE to assess the certainty of the evidence. MAIN RESULTS: We included 82 studies (74 RCTs) that included 42,273 participants in the review (71 studies, 37,237 participants included in the meta-analyses); 36 studies are new to this update. We rated 10 studies as being at low risk of bias overall (low risk in all domains assessed), 48 at high risk of bias overall (high risk in at least one domain), and the remaining 24 at unclear risk. Cessation counselling versus no counselling, grouped by intensity of intervention Hospitalised patients who received smoking cessation counselling that began in the hospital and continued for more than a month after discharge had higher quit rates than patients who received no counselling in the hospital or following hospitalisation (risk ratio (RR) 1.36, 95% confidence interval (CI) 1.24 to 1.49; 28 studies, 8234 participants; high-certainty evidence). In absolute terms, this might account for an additional 76 quitters in every 1000 participants (95% CI 51 to 103). The evidence was uncertain (very low-certainty) about the effects of counselling interventions of less intensity or shorter duration (in-hospital only counselling ≤ 15 minutes: RR 1.52, 95% CI 0.80 to 2.89; 2 studies, 1417 participants; and in-hospital contact plus follow-up counselling support for ≤ 1 month: RR 1.04, 95% CI 0.90 to 1.20; 7 studies, 4627 participants) versus no counselling. There was moderate-certainty evidence, limited by imprecision, that smoking cessation counselling for at least 15 minutes in the hospital without post-discharge support led to higher quit rates than no counselling in the hospital (RR 1.27, 95% CI 1.02 to 1.58; 12 studies, 4432 participants). Pharmacotherapy versus placebo or no pharmacotherapy Nicotine replacement therapy helped more patients to quit than placebo or no pharmacotherapy (RR 1.33, 95% CI 1.05 to 1.67; 8 studies, 3838 participants; high-certainty evidence). In absolute terms, this might equate to an additional 62 quitters per 1000 participants (95% CI 9 to 126). There was moderate-certainty evidence, limited by imprecision (as CI encompassed the possibility of no difference), that varenicline helped more hospitalised patients to quit than placebo or no pharmacotherapy (RR 1.29, 95% CI 0.96 to 1.75; 4 studies, 829 participants). Evidence for bupropion was low-certainty; the point estimate indicated a modest benefit at best, but CIs were wide and incorporated clinically significant harm and clinically significant benefit (RR 1.11, 95% CI 0.86 to 1.43, 4 studies, 872 participants). Hospital-only intervention versus intervention that continues after hospital discharge Patients offered both smoking cessation counselling and pharmacotherapy after discharge had higher quit rates than patients offered counselling in hospital but not offered post-discharge support (RR 1.23, 95% CI 1.09 to 1.38; 7 studies, 5610 participants; high-certainty evidence). In absolute terms, this might equate to an additional 34 quitters per 1000 participants (95% CI 13 to 55). Post-discharge interventions offering real-time counselling without pharmacotherapy (RR 1.23, 95% CI 0.95 to 1.60, 8 studies, 2299 participants; low certainty-evidence) and those offering unscheduled counselling without pharmacotherapy (RR 0.97, 95% CI 0.83 to 1.14; 2 studies, 1598 participants; very low-certainty evidence) may have little to no effect on quit rates compared to control. Telephone quitlines versus control To provide post-discharge support, hospitals may refer patients to community-based telephone quitlines. Both comparisons relating to these interventions had wide CIs encompassing both possible harm and possible benefit, and were judged to be of very low certainty due to imprecision, inconsistency, and risk of bias (post-discharge telephone counselling versus quitline referral: RR 1.23, 95% CI 1.00 to 1.51; 3 studies, 3260 participants; quitline referral versus control: RR 1.17, 95% CI 0.70 to 1.96; 2 studies, 1870 participants). AUTHORS' CONCLUSIONS: Offering hospitalised patients smoking cessation counselling beginning in hospital and continuing for over one month after discharge increases quit rates, compared to no hospital intervention. Counselling provided only in hospital, without post-discharge support, may have a modest impact on quit rates, but evidence is less certain. When all patients receive counselling in the hospital, high-certainty evidence indicates that providing both counselling and pharmacotherapy after discharge increases quit rates compared to no post-discharge intervention. Starting nicotine replacement or varenicline in hospitalised patients helps more patients to quit smoking than a placebo or no medication, though evidence for varenicline is only moderate-certainty due to imprecision. There is less evidence of benefit for bupropion in this setting. Some of our evidence was limited by imprecision (bupropion versus placebo and varenicline versus placebo), risk of bias, and inconsistency related to heterogeneity. Future research is needed to identify effective strategies to implement, disseminate, and sustain interventions, and to ensure cessation counselling and pharmacotherapy initiated in the hospital is sustained after discharge.

Current Pharmacotherapies for Smoking Cessation and Promising Emerging Drugs.

OBJECTIVE: Pharmacotherapy is commonly used during quit attempts and has shown an increase in the likelihood of achieving abstinence. However, with established pharmacotherapies, abstinence rates following a quit attempt remain low, and relapse is common. This review aims to investigate the efficacy and harm profiles of current and emerging pharmacotherapies. METHODS: Literature review of current and emerging pharmacotherapies for smoking cessation and tobacco use disorder. RESULTS: Emerging pharmacotherapies include new formulations of existing therapies, drug repurposing and some new treatments. New treatments are welcome and may incorporate different mechanisms of action or different safety and tolerability profiles compared to existing treatments. However, emerging pharmacotherapies have yet to demonstrate greater efficacy compared to existing treatments. The emergence of Electronic Nicotine Delivery Systems (ENDS) or 'vaping' is a feature of the current debate around tobacco use disorder. ENDS appear to facilitate switching but not quitting and are controversial as a harm minimisation strategy. LIMITATIONS: Studies included a broad range of therapies and trial designs that should be compared with their differences taken into consideration. CONCLUSION: Strategies to successfully quit smoking vary between individuals and may extend beyond pharmacotherapy and involve complex psychosocial factors and pathways.

Smoking Cessation After Initial Treatment Failure With Varenicline or Nicotine Replacement: A Randomized Clinical Trial.

Importance: Most people who smoke do not quit on their initial attempt. Objective: To determine the best subsequent strategy for nonabstinence following initial treatment with varenicline or combined nicotine replacement therapy (CNRT). Design, Setting, and Participants: Using a double-blind, placebo-controlled, sequential multiple assignment randomized trial, 490 volunteers were randomized to receive 6 weeks of varenicline or CNRT. After 6 weeks, nonabstainers were rerandomized to continue, switch, or increase medication dosage for 6 additional weeks. The study was conducted from June 2015 through October 2019 in a Texas tobacco treatment clinic. Interventions: The initial treatment was 2 mg/d of varenicline or the combined replacement therapy of a 21-mg patch plus 2-mg lozenge. The rerandomized participants either continued with their initial therapies, switched between varenicline and CNRT, or increased dosages either to 3-mg or more of varenicline or to a 42-mg patch and lozenges. All received weekly brief counseling. Main Outcomes and Measures: Biochemically verified 7-day point prevalence abstinence at the end of treatment at 12 weeks. Results: The 490 randomized participants (210 female [43%], 287 non-Hispanic White [58%], mean age, 48.1 years) smoked an average of 20 cigarettes per day. After the first phase, 54 participants in the CNRT group were abstinent and continued their therapy; of the 191 who were not abstinent, 151 were rerandomized, and the 40 who did not return for rerandomization were assigned to continue their initial CNRT condition in phase 2. The end-of-treatment abstinence rate for the 191 phase 1 nonabstainers was 8% (95% credible interval [CrI], 6% to 10%) for the 90 (47%) who continued at the dosage condition, 14% (CrI, 10% to 18%) for the 50 (33%) who increased their dosage, and 14% (95% CrI, 10% to 18%) for the 51 (34%) who switched to varenicline (absolute risk difference [RD], 6%; 95% CrI, 6% to 11%) with more than 99% posterior probability that either strategy conferred benefit over continuing the initial dosage. After the first phase, 88 participants in the varenicline group were abstinent and continued their therapy; of the 157 who were not abstinent, 122 were rerandomized and 35 who did not return for rerandomization were assigned to continue with the varenicline condition. The end-of-treatment abstinence rate for the 157 phase 1 nonabstainers was 20% (95% CrI, 16% to 26%) for the 39 (32%) who increased their varenicline dosage, 0 (95% CrI, 0 to 0) for the 41 (34%) who switched CNRT, and 3% (95% CrI, 1% to 4%) for the 77 (49%) who were assigned to the continued varenicline condition (absolute RD, -3%; 95% CrI, -4% to -1%) with more than 99% posterior probability that continuing varenicline at the initial dosage was worse than switching to a higher dosage. Furthermore, increasing the varenicline dosage had an absolute RD of 18% (95% CrI, 13% to 24%) and a more than 99% posterior probability of conferring benefit. The secondary outcome of continuous abstinence at 6 months indicated that only increased dosages of the CNRT and varenicline provided benefit over continuation of the initial treatment dosages. Conclusions and Relevance: For individuals who smoked but did not achieve abstinence after treatment with varenicline, increasing the dosage enhanced abstinence vs continuing, whereas for nonabstainers initially treated with CNRT, a dosage increase or switch to varenicline enhanced abstinence and may be viable rescue strategies. Trial Registration: ClinicalTrials.gov Identifier: NCT02271919.

Economic Evaluation of Enhanced vs Standard Varenicline Treatment for Tobacco Cessation.

Importance: Smoking is the leading preventable cause of death and illness in the US. Identifying cost-effective smoking cessation treatment may increase the likelihood that health systems deliver such treatment to their patients who smoke. Objective: To evaluate the cost-effectiveness of standard vs enhanced varenicline use (extended varenicline treatment or varenicline in combination with nicotine replacement therapy) among individuals trying to quit smoking. Design, Setting, and Participants: This economic evaluation assesses the Quitting Using Intensive Treatments Study (QUITS), which randomized 1251 study participants who smoked into 4 conditions: (1) 12-week varenicline monotherapy (n = 315); (2) 24-week varenicline monotherapy (n = 311); (3) 12-week varenicline combination treatment with nicotine replacement therapy patch (n = 314); or (4) 24-week varenicline combination treatment with nicotine replacement therapy patch (n = 311). Study enrollment occurred in Madison and Milwaukee, Wisconsin, between November 11, 2017, and July 2, 2020. Statistical analysis took place from May to October 2023. Main Outcomes and Measures: The primary outcome was 7-day point prevalence abstinence (biochemically confirmed with exhaled carbon monoxide level ≤5 ppm) at 52 weeks. The incremental cost-effectiveness ratio (ICER), or cost per additional person who quit smoking, was calculated using decision tree analysis based on abstinence and cost for each arm of the trial. Results: Of the 1251 participants, mean (SD) age was 49.1 (11.9) years, 675 (54.0%) were women, and 881 (70.4%) completed the 52-week follow-up. Tobacco cessation at 52 weeks was 25.1% (79 of 315) for 12-week monotherapy, 24.4% (76 of 311) for 24-week monotherapy, 23.6% (74 of 314) for 12-week combination therapy, and 25.1% (78 of 311) for 24-week combination therapy, respectively. The total mean (SD) cost was $1175 ($365) for 12-week monotherapy, $1374 ($412) for 12-week combination therapy, $2022 ($813) for 24-week monotherapy, and $2118 ($1058) for 24-week combination therapy. The ICER for 12-week varenicline monotherapy was $4681 per individual who quit smoking and $4579 per quality-adjusted life-year (QALY) added. The ICER for 24-week varenicline combination therapy relative to 12-week monotherapy was $92 000 000 per additional individual who quit smoking and $90 000 000 (95% CI, $15 703 to dominated or more costly and less efficacious) per additional QALY. Conclusions and Relevance: This economic evaluation of standard vs enhanced varenicline treatment for smoking cessation suggests that 12-week varenicline monotherapy was the most cost-effective treatment option at the commonly cited threshold of $100 000/QALY. This study provides patients, health care professionals, and other stakeholders with increased understanding of the health and economic impact of more intensive varenicline treatment options.

Could GLP-1 Receptor Agonists Like Semaglutide Treat Addiction, Alzheimer Disease, and Other Conditions?

This Medical News story examines other potential uses of GLP-1 receptor agonists, the popular type 2 diabetes and weight-loss drugs.

Impact of the disruption in supply of varenicline since 2021 on smoking cessation in England: A population study.

BACKGROUND AND AIMS: Varenicline is one of the most effective smoking cessation treatments. Its supply in England was disrupted in July 2021 due to nitrosamine impurities found by its supplier, Pfizer. This study measured the impact of this disruption on smoking cessation in England. DESIGN, SETTING AND PARTICIPANTS: The study used repeated cross-sectional surveys conducted monthly, from June 2018 to December 2022. Set in England, it comprised a total of 3024 adults who reported smoking during the past year and had made at least one serious attempt to quit in the past 6 months. MEASUREMENTS: Generalized additive models analyzed the association of the varenicline supply disruption with the trend in self-reported varenicline use in the most recent quit attempt. We used these results to estimate the population-level impact of the disruption on smoking cessation. FINDINGS: Before July 2021, the proportion of past 6-month quit attempts using varenicline was stable at approximately 3.9% [risk ratio (RR)trend = 1.034, 95% confidence interval (CI) = 0.823-1.298]. The trend in varenicline use has changed sharply since the supply disruption (RRΔtrend = 0.297, 95% CI = 0.120-0.738), with prevalence falling by 69.3% per year since; from 4.1% in June 2021 to 0.8% in December 2022. Convergently, National Health Service general practitioner prescribing data reported that just 0.1% of prescriptions for smoking cessation treatments in December 2022 were for varenicline. Assuming that varenicline does not return to the market, we estimate that this could result in ~8400 fewer people stopping smoking for at least 6 months, ~4200 fewer long-term ex-smokers and ~1890 more avoidable deaths each year. CONCLUSIONS: In England, the disruption in supply of varenicline since 2021 has coincided with a substantial fall in the use of varenicline in attempts to quit smoking.

Efficacy of varenicline or bupropion and its association with nicotine metabolite ratio among smokers with COPD.

BACKGROUND AND OBJECTIVE: Nicotine metabolic ratio (NMR) has been associated with nicotine metabolism and smoking characteristics. However, there are few studies on the potential association between NMR and smoking cessation efficacy in smokers with chronic obstructive pulmonary disease (COPD) in China or elsewhere. METHODS: This study was a stratified block randomized controlled trial for smoking cessation in Chinese smokers with COPD. NMR was used as a stratification factor; slow metabolizers were defined as those with NMR <0.31, and normal metabolizers as those with NMR ≥0.31. Participants were randomly assigned to the varenicline or bupropion group. Follow-up visits were conducted at 1, 2, 4, 6, 9, 12 and 24 weeks. RESULTS: Two hundred twenty-four participants were recruited and analysed from February 2019 to June 2022. In normal metabolizers, the 9-12 weeks continuous abstinence rate of varenicline (43.1%) was higher than in bupropion (23.5%) (OR = 2.47, 95% CI 1.05-5.78, p = 0.038). There was no significant difference in abstinence rates between treatment groups in slow metabolizers (54.1% vs. 45.9%, OR = 1.39, 95% CI 0.68-2.83, p = 0.366). For slow metabolizers, the total score of side effects in the varenicline group was significantly higher than the bupropion group (p = 0.048), while there was no significant difference in side effects between groups for normal metabolizers (p = 0.360). CONCLUSION: Varenicline showed better efficacy than bupropion in normal metabolizers, and bupropion showed equivalent efficacy in slow metabolizers with less side effects. According to our study, NMR provides a better justification for both scientific research and tailoring optimal pharmacotherapy for smoking cessation among smokers in COPD.

Incremental net monetary benefit of using varenicline for smoking cessation: A systematic review and meta-analysis of economic evaluation studies.

AIMS: To conduct a systematic review and meta-analysis and pool the incremental net benefits (INBs) of varenicline compared with behaviour support with bupropion or nicotine replacement therapy (NRT), behaviour support alone and unaided cessation in adult smokers making a first-time attempt to quit. METHODS: A search for economic evaluation studies was conducted from inception to 30 September 2022, on PubMed, Embase, Cost-Effectiveness Analysis (CEA) Registry by Tufts Medical Centre, EconLit and the NHS Economic Evaluation Database (NHS EED). Eligible studies were included if they were (1) conducted among adults ages 18 years old and older who were smokers attempting to quit for the first time; (2) compared varenicline to behaviour support with bupropion or NRT, behaviour support alone and unaided cessation; and (3) performed a CEA or cost-utility analysis. The INBs were calculated and pooled across studies stratified by country income level and study perspective using the random-effects model. Statistical heterogeneity between studies was assessed using the I2 statistic and Cochrane Q statistic. RESULTS: Of the 1433 identified studies, 18 studies were included in our review. Our findings from healthcare system/payer perspective suggested that the use of varenicline is statistically significantly cost-effective compared with bupropion (pooled INB, $830.75 [95% confidence interval, $208.23, $1453.28]), NRTs ($636.16 [$192.48, $1079.84]) and unaided cessation ($4212.35 [$1755.79, $6668.92]) in high-income countries. Similarly, varenicline is also found to be cost-effective compared to bupropion ($2706.27 [$1284.44, $4128.11]), NRTs ($3310.01 [$1781.53, $4838.50]) and behavioural support alone ($5438.22 [$4105.99, $6770.46]) in low- and middle-income countries. CONCLUSION: Varenicline is cost-effective as a smoking cessation aid when compared with behavioural support with bupropion or nicotine replacement therapies and behavioural support alone in both high-income countries and low- and middle-income countries, from the healthcare system/payer perspective in adult smokers who attempt to quit for the first time.

Genetic Prediction of Smoking Cessation Medication Side Effects: A Genome-Wide Investigation of Abnormal Dreams on Varenicline.

Varenicline, the most efficacious smoking cessation monotherapy, produces abnormal dreams. Although genetic contributions to varenicline-associated nausea and cessation have been identified, the role of genetics in abnormal dreams is unknown. We conducted a genomewide association study (GWAS) of abnormal dreams in 188 European ancestry smokers treated with varenicline (NCT01314001). Additive genetic models examined the likelihood of experiencing abnormal dreams 2 weeks following varenicline initiation. For the top locus, we tested for selectivity to varenicline, effects on cessation, replication, and generalizability to African ancestry (AA) individuals. The top GWAS variant associated with abnormal dreams was rs901886, mapping to intron 2 of ICAM5 on chromosome 19. The prevalence of abnormal dreams in those with rs901886 CC, CT, and TT genotypes was 15%, 36%, and 62%, respectively (odds ratio = 2.94 for T vs. C, 95% confidence interval = 1.92-4.55, P = 2.03e-7; T allele frequency = 52%). This rs901886 association was selective to varenicline (P values > 0.05 on nicotine patch and placebo). There were also positive associations for rs901886 T (vs. C allele, P = 0.03) and for abnormal dreams (P = 0.06) with varenicline-aided cessation. Neither rs901886 (P = 0.40) nor abnormal dreams (P = 0.24) were associated with adherence. A similar direction of effect of rs901886 on abnormal dreams was observed in a second varenicline trial (NCT01836276). In AA individuals (n = 137), rs901886 was not associated with abnormal dreams (P = 0.41), but there was an association for a variant located ~ 74.4 kb 5' of ICAM5 (P = 2.56e-3). Variation in ICAM5 may influence abnormal dreams and cessation on varenicline. These findings provide additional support for genetically optimized smoking cessation approaches.

Cytisinicline for Smoking Cessation: A Randomized Clinical Trial.

Importance: Cytisinicline (cytisine) is a plant-based alkaloid that, like varenicline, binds selectively to α4ß2 nicotinic acetylcholine receptors, which mediate nicotine dependence. Although not licensed in the US, cytisinicline is used in some European countries to aid smoking cessation, but its traditional dosing regimen and treatment duration may not be optimal. Objective: To evaluate the efficacy and tolerability of cytisinicline for smoking cessation when administered in a novel pharmacokinetically based dosing regimen for 6 or 12 weeks vs placebo. Design, Setting, and Participants: A 3-group, double-blind, placebo-controlled, randomized trial (ORCA-2) compared 2 durations of cytisinicline treatment (6 or 12 weeks) vs placebo, with follow-up to 24 weeks, among 810 adults who smoked cigarettes daily and wanted to quit. It was conducted at 17 US sites from October 2020 to December 2021. Interventions: Participants were randomized (1:1:1) to cytisinicline, 3 mg, 3 times daily for 12 weeks (n = 270); cytisinicline, 3 mg, 3 times daily for 6 weeks then placebo 3 times daily for 6 weeks (n = 269); or placebo 3 times daily for 12 weeks (n = 271). All participants received behavioral support. Main Outcomes and Measures: Biochemically verified continuous smoking abstinence for the last 4 weeks of cytisinicline treatment vs placebo (primary) and from end of treatment to 24 weeks (secondary). Results: Of 810 randomized participants (mean age, 52.5 years; 54.6% female; mean of 19.4 cigarettes smoked daily), 618 (76.3%) completed the trial. For the 6-week course of cytisinicline vs placebo, continuous abstinence rates were 25.3% vs 4.4% during weeks 3 to 6 (odds ratio [OR], 8.0 [95% CI, 3.9-16.3]; P < .001) and 8.9% vs 2.6% during weeks 3 to 24 (OR, 3.7 [95% CI, 1.5-10.2]; P = .002). For the 12-week course of cytisinicline vs placebo, continuous abstinence rates were 32.6% vs 7.0% for weeks 9 to 12 (OR, 6.3 [95% CI, 3.7-11.6]; P < .001) and 21.1% vs 4.8% during weeks 9 to 24 (OR, 5.3 [95% CI, 2.8-11.1]; P < .001). Nausea, abnormal dreams, and insomnia occurred in less than 10% of each group. Sixteen participants (2.9%) discontinued cytisinicline due to an adverse event. No drug-related serious adverse events occurred. Conclusions and Relevance: Both 6- and 12-week cytisinicline schedules, with behavioral support, demonstrated smoking cessation efficacy and excellent tolerability, offering new nicotine dependence treatment options. Trial Registration: ClinicalTrials.gov Identifier: NCT04576949.