Nicotine delivery systems

Nicotine and Cotinine Induce Neutrophil Extracellular Trap Formation-Potential Risk for Impaired Wound Healing in Smokers

Smoking undoubtedly affects human health. Investigating 2318 representative patients at a level 1 trauma center identified delayed wound healing, tissue infections, and/or sepsis as main complications in smokers following trauma and orthopedic surgery. Therefore, smoking cessation is strongly advised to improve the clinical outcome in these patients, although smoking cessation often fails despite nicotine replacement therapy raising the need for specific interventions that may reduce the complication rate. However, the underlying mechanisms are still unknown. In diabetics, delayed wound healing and infections/sepsis are associated with increased neutrophilic PADI4 expression and formation of neutrophil extracellular traps (NETs). The aim was to investigate if similar mechanisms hold for smokers. Indeed, our results show higher PADI4 expression in active and heavy smokers than non-smokers, which is associated with an increased complication rate. However, in vitro stimulation of neutrophils with cigarette smoke extract (CSE) only moderately induced NET formation despite accumulation of reactive oxygen species (ROS). Physiological levels of nicotine and its main metabolite cotinine more effectively induced NET formation, although they did not actively induce the formation of ROS, but interfered with the activity of enzymes involved in anti-oxidative defense and NET formation. In summary, we propose increased formation of NETs as possible triggers for delayed wound healing, tissue infections, and/or sepsis in smokers after a major trauma and orthopedic surgery. Smoking cessation might reduce this effect. However, our data show that smoking cessation supported by nicotine replacement therapy should be carefully considered as nicotine and its metabolite cotinine effectively induced NET formation in vitro, even without active formation of ROS.

Electrically controlled nicotine delivery through Carbon nanotube membranes via electrochemical oxidation and nanofluidically enhanced electroosmotic flow

A promising tool for nicotine addiction treatment is a programmable nicotine delivery device coupled to smart phone-assisted behavioral therapies. Key metrics for such a device are delivery of adjustable nicotine doses tailored to individual needs, compact size and power efficiency. Reported here is a detailed optimization of carbon nanotube (CNT) membrane fabrication based on electrochemical oxidation, to improve its electrically driven performance for nicotine fluxes and switching ON (-1.5 V)-OFF (0 V) flux ratio. ON- state nicotine flux of ~ 6 µmoles/cm²/h at -1.5 V applied bias was achieved allowing ~ 6-folds decrease in the size of device (4 cm²) to attain flux equivalent to high dose nicotine gum (1.1 µmoles/cm²/h). Application of + 1.5 V bias in OFF state reduced diffusional background flux, giving an ON (-1.5 V)/OFF (+ 1.5 V) flux ratio of 68 that enabled device to deliver between the highest nicotine gum (1.1 µmoles/cm²/h) and lowest nicotine patch (0.08 µmoles/cm²/h) doses, as well as taper off nicotine doses for long term addiction treatment. The nicotine transport mechanism was studied as a function of pH and applied bias, using neutral tracer molecule, showing a mechanism of both electroosmosis and electrophoresis in the atomically smooth nanofluidic pores of CNTs. Optimal power consumption/flux efficiency of 111(µW/cm²)/µmoles/cm²/h was achieved allowing watch-battery lifetimes of 7-62 days for conventional treatment dosing regimens. Bluetooth-enabled, remotely controlled CNT membrane system has potential for treatments of nicotine, opioid and alcohol addictions that needs dose adjustment with precise temporal control.

Nicotine Facilitation of Conditioned Place Preference to Food Reward in Humans

Nicotine has recently been shown to enhance the motivational value of non-nicotine stimuli in nonhumans. To investigate whether nicotine also enhances reward in humans, we used a virtual translation of the conditioned place preference (CPP) paradigm to examine nicotine's reward-enhancing effects using a low-dose 2 mg nicotine lozenge targeted to a mild use population. Methods: Sixty-eight nicotine-using undergraduates were randomly assigned to receive either a 2 mg nicotine or placebo lozenge prior to conditioning. During each of six, three-minute conditioning sessions, participants were confined to one of two VR rooms. In one room, they received real chocolate M&Ms, whereas no M&Ms were administered in the other room. Following conditioning, a three-minute free-access test session occurred during which participants had unrestricted access to both rooms without reward. Results: Individuals who received nicotine demonstrated a CPP by spending significantly more time in the room previously paired with M&Ms compared to the unrewarded room (p = 0.04). Those who received placebo did not demonstrate a CPP (p > 0.05). Moreover, we observed no significant differences between treatment groups in terms of the amount of time spent in each virtual room. Conclusion: While nicotine seems to facilitate CPP expression for a virtual environment previously paired with chocolate food rewards, further characterization of the mechanism by which this occurs is needed.

Constituents of "teabacco": A forensic analysis of cigarettes made from diverted nicotine replacement therapy lozenges in smoke-free prisons

Following the implementation of prison smoke-free policies, there have been reports of prisoners creating substitute cigarettes made from nicotine replacement therapy patches or lozenges infused with tea leaves ("teabacco"). No studies have analyzed the chemical constituents of teabacco made from nicotine lozenges, so as to document any potential related health hazards. Teabacco samples were made by a participant who reported creating teabacco while incarcerated in a smoke-free prison in Queensland, Australia, and the process was video-recorded for replication in a laboratory. A simple linear smoking system captured the teabacco smoke for analysis. Inductively coupled plasma optical emission spectroscopy (ICP-OES) was used to analyze elemental composition and gas chromatography coupled with a mass spectrometer (GC-MS) analyzed the captured smoke using the National Institute of Standards and Technology mass spectral library. Analyses determined that quantities of copper, aluminum, and lead concentrations, and levels of inhaled total particulate matter, were above recommended guidelines for safe ingestion. Analysis of teabacco smoke using GC-MS identified potentially toxic compounds catechol and nicotine. However, our findings show that smoking this form of teabacco is less harmful than smoking teabacco made from nicotine patches, or smoking traditional tobacco cigarettes. Considering the limited potential health harm of smoking teabacco made from lozenges, and that nicotine lozenges represent the only form of smoking cessation support for individuals entering smoke-free prisons, we caution against the removal of nicotine lozenges from Queensland's prisons, at least until further research directly establishes health harms associated with this form of teabacco.

Investigating the role of ion-pair strategy in regulating nicotine release from patch: Mechanistic insights based on intermolecular interaction and mobility of pressure sensitive adhesive

The aim of this study was to prepare a drug-in-adhesive patch of nicotine (NIC) and use ion-pair strategy to regulate drug delivery rate. Moreover, the mechanism of how ion-pair strategy regulated drug release was elucidated at molecular level. Formulation factors including pressure sensitive adhesives (PSAs), drug loading and counter ions (C₄, C₆, C₈, C₁₀, and C₁₂) were screened. In vitro release experiment and in vitro transdermal experiment were conducted to determine the rate-limiting step in drug delivery process. FT-IR and molecular modeling were used to characterize the interaction between drug and PSA. Thermal analysis and rheology study were conducted to investigate the mobility variation of PSA. The optimized patch prepared with NIC-C₈ had the transdermal profile fairly close to that of the commercial product (p > 0.05). The release rate constants (k) of NIC, NIC-C₄ and NIC-C₁₀ were 21.1, 14.4 and 32.4, respectively. Different release rates of NIC ion-pair complexes were attributed to the dual effect of ion-pair strategy on drug release. On one hand, ion-pair strategy enhanced the interaction between drug and PSA, which inhibited drug release. On the other hand, using ion-pair strategy improved the mobility of PSA, which facilitated drug release. Drug release behavior was determined by combined effect of two aspects above. These conclusions provided a new idea for us to regulate drug release behavior from patch.

A systematic review of possible serious adverse health effects of nicotine replacement therapy

We conducted a systematic literature review to identify and critically evaluate studies of serious adverse health effects (SAHEs) in humans using nicotine replacement therapy (NRT) products. Serious adverse health effects refer to adverse events, leading to substantial disruption of the ability to conduct normal life functions. Strength of evidence evaluations and conclusions were also determined for the identified SAHEs. We evaluated 34 epidemiological studies and clinical trials, relating NRT use to cancer, reproduction/development, CVD, stroke and/or other SAHEs in patients, and four meta-analyses on effects in healthy populations. The overall evidence suffers from many limitations, the most significant being the short-term exposure (≤12 weeks) and follow-up to NRT product use in most of the studies, the common failure to account for changes in smoking behaviour following NRT use, and the sparse information on SAHEs by type of NRT product used. The only SAHE from NRT exposure we identified was an increase in respiratory congenital abnormalities reported in one study. Limited evidence indicated a lack of effect between NRT exposure and SAHEs for CVD and various reproduction/developmental endpoints. For cancer, stroke and other SAHEs, the evidence was inadequate to demonstrate any association with NRT use. Our conclusions agree with recent statements from authoritative bodies.

Intermittent hypercapnic hypoxia effects on the nicotinic acetylcholine receptors in the developing piglet hippocampus and brainstem

This study investigated the effects of acute (1 day) vs repeated (4 days) exposure to intermittent hypercapnic hypoxia (IHH) on the immunohistochemical expression of α2, α3, α5, α7, α9 and β2 nicotinic acetylcholine receptor (nAChR) subunits in the developing piglet hippocampus and brainstem medulla, and how prior nicotine exposure alters the response to acute IHH. Five piglet groups included: 1day IHH (1D IHH, n=9), 4days IHH (4D IHH, n=8), controls exposed only to air cycles for 1day (1D Air, n=6) or 4days (4D Air, n=5), and pre-exposed to nicotine for 13days prior to 1day IHH (Nic+1D IHH, n=7). The exposure period alternated 6min of HH (8%O₂, 7%CO₂, balance N₂) and 6min of air over 48min, while controls were switched from air-to-air. Results showed that: 1. repeated IHH induces more changes in nAChR subunit expression than acute IHH in both the hippocampus and brainstem medulla, 2. In the hippocampus, α2 and β2 changed the most (increased) following IHH and the CA3, CA2 and DG were mostly affected. In the brainstem medulla, α2, α5, α9 and β2 were changed (decreased) in most nuclei with the hypoglossal and nucleus of the solitary tract being mostly affected. 3. Pre-exposure to nicotine enhanced the changes in the hippocampus but dampened those in the brainstem medulla. These findings indicate that the nAChRs (predominantly with the α2/β2 complex) are affected by IHH in critical hippocampal and brainstem nuclei during early brain development, and that pre-exposure to nicotine alters the pattern of susceptibility to IHH.

The effect of acute exercise on cigarette cravings while using a nicotine lozenge

RATIONALE

It is imperative that smoking cessation aids effectively alleviate cigarette craving and withdrawal symptoms because their intensity has shown to predict relapse. The nicotine lozenge and a single session of exercise have both been shown to provide relief from craving for smokers who have stopped smoking. These two efficacious monotherapies have distinct mechanic pathways, and applying them concurrently may provide additive-craving relief benefit.

OBJECTIVE

This study aimed to examine whether an acute bout of moderate-intensity exercise provides additional craving relief to the nicotine replacement lozenge in recently quit smokers.

RESULTS

Thirty smokers who had abstained from smoking for 15 h were randomized to either the experimental (exercise and lozenge, n = 15) or control (lozenge alone, n = 15) condition. Craving was assessed before (baseline), during (10 and 20 min), and after (10, 20, 30, and 40 min) treatment.

RESULT

A significant condition by time interaction effect was found for craving (F(6, 23) = 2.70, p = 0.039, Wilks' Λ = 0.59, η ρ (2) = 0.41). While both conditions demonstrated reductions in craving, the reduction was significantly greater for the experimental group.

CONCLUSION

These findings demonstrate that an acute bout of exercise provides additional craving relief to the nicotine lozenge in recently quit smokers. We recommend smokers who attempt to quit employ both cessation aids simultaneously to maximize reductions in cravings.

The impact of anticipated and unanticipated smoking opportunities on cigarette smoking and nicotine lozenge responses

BACKGROUND

Perceptions regarding the availability of smoking opportunities are known to affect cigarette craving; however, whether they impact actual smoking or how smokers respond to acute nicotine replacement therapy (NRT) administration is not known. This study examined the impact of pharmacological and expectancy components of NRT administration on craving and smoking in smokers anticipating or not anticipating an imminent smoking opportunity.

METHODS

In total, 154 smokers (84 male) completed an experimental session in which instructions regarding the nicotine content of a lozenge (4 mg vs. no nicotine) and regarding the availability of a future smoking opportunity were manipulated. Cigarette craving was assessed before and after manipulations and lozenge administration. All participants were then allotted 1h to self-administer as many cigarette puffs as they wished.

RESULTS

Unanticipated smoking opportunities reduced latency to self-administration (p<0.001), regardless of nicotine expectancy or pharmacology. When analyses included all participants, nicotine reduced intentions to smoke (p=0.016) and withdrawal-related craving (p=0.043) regardless of expectancy. Conversely, analyses using only "believers" of the nicotine content instructions revealed that nicotine expectancy reduced intentions to smoke (p=0.034) and withdrawal-related craving (p=0.047) regardless of actual nicotine administration. "Believers" also reported increased withdrawal-related craving when a smoking opportunity was perceived to be imminent (p=0.041). These effects were not significant when analyses included all participants.

CONCLUSIONS

Findings suggest that unexpected smoking opportunities may be more appealing than expected ones regardless of perceived or actual acute NRT use. They also highlight the importance of reporting balanced placebo findings using all participants as well as "believers" only.

The impact of nicotine lozenges and stimulus expectancies on cigarette craving

Reduced craving associated with nicotine replacement therapy use is frequently attributed to the effects of nicotine pharmacology, however non-pharmacological factors may also play a role. This study examined the impact of nicotine pharmacology and non-pharmacological components of an acute nicotine lozenge (4 mg) on cigarette craving, mood and heart rate in 70 daily smokers (36 male). Smoking-related stimuli were used to assess cue-induced craving. Participants were randomly assigned to one of four conditions in a balanced placebo design where half the participants were provided deceptive information regarding the nicotine content of a lozenge. Subjective ratings of craving and mood were collected and heart rate was assessed before and after neutral and smoking cues. Nicotine expectancy reduced withdrawal-related craving (p = 0.006) regardless of actual nicotine administration while combined nicotine expectancy and administration reduced intentions to smoke (p = 0.046) relative to each of the other conditions. Exposure to smoking-related stimuli increased cigarette craving (p ≤ 0.001) and negative affect (p ≤ 0.001) regardless of expectancy or pharmacology. Following the smoking cue, women reported a greater increase in withdrawal-related craving than men (p = 0.027). Findings suggest that both pharmacological and non-pharmacological components of nicotine lozenge administration contribute to its acute effects on craving, yet neither appears effective in preventing craving triggered by exposure to environmental smoking stimuli.

Novel delivery systems for nicotine replacement therapy as an aid to smoking cessation and for harm reduction: rationale, and evidence for advantages over existing systems

Nicotine replacement therapy (NRT) has been used in the treatment of tobacco dependence for over three decades. Whilst the choice of NRT was limited early on, in the last ten years there has been substantial increase in the number of nicotine delivery devices that have become available. This article briefly summarises existing forms of NRT, evidence of their efficacy and use, and reviews the rationale for the development of novel products delivering nicotine via buccal, transdermal or pulmonary routes (including nicotine mouth spray, nicotine films, advanced nicotine inhalers and electronic cigarettes). It presents available evidence on the efficacy, tolerability and abuse potential of these products, with a focus on their advantages as well as disadvantages compared with established forms of NRT for use as an aid to both smoking cessation as well as harm reduction.

The influence of acutely administered nicotine on cue-induced craving for gambling in at-risk video lottery terminal gamblers who smoke

Evidence indicates that tobacco use and gambling often co-occur. Despite this association, little is known about how tobacco use affects the propensity to gamble. Nicotine, the putative addictive component of tobacco, has been reported to potentiate the hedonic value of other nonsmoking stimuli. Environmental cues have been identified as an important contributor to relapse in addictive behavior; however, the extent to which nicotine can affect the strength of gambling cues remains unknown. This study examined whether nicotine influences subjective ratings for gambling following gambling cues. In a mixed within/between-subjects design, 30 (20 men) video lottery terminal (VLT) gamblers ('moderate-risk' or 'problem' gamblers) who smoke daily were assigned to nicotine (4 mg deliverable) or placebo lozenge conditions. Subjective and behavioral responses were assessed at baseline, following lozenge, following neutral cues, and following presentation of gambling cues. Nicotine lozenge was found to significantly reduce tobacco-related cravings (P<0.05) but did not affect gambling-related cravings, the choice to play a VLT, or other subjective responses. These results suggest that a low dose of acutely administered nicotine does not increase cue-induced craving for gambling in at-risk VLT gamblers who smoke.

Long-acting Preparations in Substance Abuse Management: A Review and Update

Many pharmacological approaches have been used in managing substance use disorders. Conventional pharmacological agents have relatively short durations of action which make them vulnerable to non-adherence and relapse to substance use disorder. To overcome this problem, long-acting preparations have been developed with the aim of reducing the frequency of use and hence improving adherence. This review takes a broad overview of the long-acting preparations available for the management of substance use disorders. The pharmacology, advantages and disadvantages of these preparations are discussed. Many of these preparations hold promise for improving patient outcomes.

Effects of transdermal nicotine and concurrent smoking on cognitive performance in tobacco-abstinent smokers

Smokers experience cognitive decrements during tobacco abstinence and boosts in performance on resumption of smoking. Few studies have examined whether smoking cessation treatments such as transdermal nicotine (TN) ameliorate these decrements or attenuate the cognitive effects of smoking. Identifying the effects of nicotine on these tobacco-related changes in performance could guide the development of more efficacious treatments. The purpose of this double-blind, randomized, laboratory study was to use process-specific cognitive tasks to examine the effects of TN and tobacco smoking on attention and working memory in overnight-abstinent smokers (N = 124; 54 women). Each participant completed 4 sessions lasting 6.5 hr corresponding to 0-, 7-, 14-, or 21-mg TN doses, and smoked a single cigarette 4 hr after TN administration. Outcome measures were administered before and after smoking and included tasks measuring attention (alerting, orienting, and executive function), working memory (verbal and spatial), and psychomotor function. Analysis of variance (p < .05) revealed that TN improved verbal and spatial working memory performance, as well as psychomotor function. Smoking, independent of TN dose, improved alerting, verbal working memory, and psychomotor function. Lastly, TN partially attenuated the effects of smoking on some working memory outcomes. These findings lend evidence to the idea that TN ameliorates some abstinence-related cognitive decrements and suggest that TN does not completely attenuate the cognitive effects of a concurrently smoked cigarette. Consequently, TN's efficacy as a smoking cessation treatment might be improved if these limitations are better addressed by either modifying or supplementing existing treatments.

Comparison of available treatments for tobacco addiction

Cigarette smoking is a major public health problem that causes more than 5 million deaths annually worldwide. Cigarette smoking is especially common among individuals with psychiatric comorbidity, including individuals with primary psychiatric disorders and other addictions. Effective behavioral and pharmacologic treatments for smoking cessation are available. Behavioral treatments including brief (< 3 min) counseling by physicians are effective. Seven first-line pharmacologic treatments are currently available: five nicotine replacement therapies, bupropion, and varenicline. In addition, clonidine and nortriptyline are second-line treatments for smoking cessation. These treatments increase the chances of quitting smoking by two- to threefold, supporting their use in smokers who are motivated to quit. However, effective treatments for many subpopulations, including smokers with psychiatric comorbidities as well as adolescent, pregnant, or postpartum smokers, remain to be developed and represent an important challenge.

Pharmacogenetics of smoking cessation therapy

Nicotine dependence is a major health problem, with a large amount of smoking-related premature deaths and disabilities. The dependence mechanism of nicotine is especially complex and is under strong genetic influence. Smoking cessation is associated with substantial health benefits. Evidence from animal and human studies suggests that genetic polymorphisms influencing pharmacokinetics and pharmacodynamics of nicotine may have great potential for aiding smoking treatment. There are more than 30 association studies and one genome-wide association study (GWAS) between genetic polymorphisms and smoking cessation following nicotine replacement therapy (NRT) and/or bupropion therapy. However, only a few candidate genes or regions were analyzed more than twice and even these genes require additional investigations in different therapeutic schemes. There are a growing number of new pharmacologic options that have not been pharmacogenetically assessed according to published literature. In addition, molecular genetics studies are needed to assess the functional mechanisms of some putative association results. Taken together, the preliminary findings are promising but raise the need for new studies with adequate sample sizes and adjustment for several potential confounding factors frequently neglected, such as comorbidity and sociodemographic factors. The current state of the art in the field encourages an optimist view that personalized treatment approaches may become possible. However, the current scientific evidence still does not support the use of pharmacogenetic tests in routine smoking cessation therapy.

Novel pharmacological approaches for treating tobacco dependence and withdrawal: current status

Increasing the diversity and availability of medications for the treatment of tobacco dependence and/or withdrawal, to aid in the achievement of smoking cessation, is crucial to meet the diverse needs of tobacco users. Despite a general awareness that smoking is harmful and widespread interest in smoking cessation, nearly 50 million adults in the US and 1.3 billion worldwide continue to smoke. Nicotine replacement therapies are effective in the treatment of tobacco dependence and withdrawal, but do not meet the needs of all tobacco users. Improvement of tobacco dependence and/or withdrawal treatments is likely to rely on novel pharmacological approaches that include new chemical entities and new formulations of current drugs. In addition, new indications for treating tobacco dependence and withdrawal show promise for reducing tobacco use and associated disease. This article focuses on a range of novel pharmacological approaches for the treatment of tobacco dependence and/or withdrawal, including oral and pulmonary nicotine delivery and the following non-nicotinic medications: antidepressants, an alpha4beta2 nicotine partial agonist, an alpha2-noradrenergic agonist, cytochrome P450 (CYP) 2A6 inhibitors, opioid antagonists and GABAergic medications. In addition to existing medications, this article addresses novel medications in the clinical development stage and those that have been evaluated previously. Novel medications in the clinical development stage include at least three nicotine vaccines and the cannabinoid receptor acting drug rimonabant. Medications evaluated previously include lobeline, mecamylamine and an anticholinergic drug regimen comprising atropine, scopolamine and chlorpromazine. Having not been approved by major drug regulatory authorities for the treatment of tobacco dependence and/or withdrawal, these medications have been evaluated in an experimental capacity.

Effect of smokeless tobacco product marketing and use on population harm from tobacco use policy perspective for tobacco-risk reduction

This article presents policy perspectives on the marketing of smokeless tobacco products to reduce population harm from tobacco use. Despite consensus that smokeless tobacco products as sold in the United States are less dangerous than cigarettes, there is no consensus on how to proceed. Diverse factions have different policy concerns. While the tobacco industry is exempted from U.S. Food and Drug Administration (FDA) oversight, the pharmaceutical industry whose nicotine replacement therapy (NRT) medicines compete with smokeless tobacco as noncombustible nicotine-delivery systems are regulated by the FDA. Some public health experts support smokeless tobacco use to reduce population harm from tobacco; other public health experts oppose promoting smokeless tobacco for harm reduction. Adult consumers can freely purchase currently-marketed smokeless tobacco products and even more-deadly cigarettes. Concerns with and advantages of smokeless tobacco products are discussed. In that noncombustible medicinal nicotine-delivery systems have been proven to be effective smoking-cessation aids, smokeless tobacco, as another source of psychoactive doses of nicotine, could be used similarly, in a dose-response fashion as a smoking-cessation aid (consistent with FDA principles for evaluating generic versions of drugs). Price measures should be used on tobacco products to make costs to consumers proportional to product health risks (which would make smokeless tobacco much cheaper than cigarettes), and smokeless tobacco should be encouraged as an option for smoking cessation in adult smokers, particularly for those who have failed to stop smoking using NRT or other methods.

Pharmacokinetics, safety and efficacy from randomized controlled trials of 1 and 2 mg nicotine bitartrate lozenges (Nicotinell)

BACKGROUND

The use of nicotine replacement therapy (NRT) can almost double the chances of success for smokers to quit. Nevertheless, there is still a considerable number of cessation attempts that are made without any treatment. This novel oral formulation, (lozenge containing nicotine bitartrate dihydrate) has been developed to enlarge the offer for efficient smoking cessation drug therapies, assuming that increasing treatment options will bring more smokers to find the support they personally need to stop smoking.

METHODS

Three pharmacokinetic (PK), one safety and two efficacy studies were carried out with Nicotinell lozenges. PK trials were: (1) a single-dose, three-way crossover study comparing 1 and 2 mg lozenges with 2 mg nicotine gum; (2) a multiple-dose, two-way crossover study comparing 1 mg lozenge with 2 mg gum; (3) a multiple-dose, three-way crossover study comparing 1 and 2 mg lozenges with 4 mg gum. Safety trial: (4) a single dose study to assess the safety of swallowing up to 12 lozenges containing 1 mg nicotine. Efficacy trials: two efficacy studies in (5) France and (6) the USA, including more than 900 smokers followed-up for up to one year, conducted with the 1 mg lozenge.

RESULTS

The results of the individual PK trials showed that the 1 mg Nicotinell lozenge is bioequivalent to 2 mg polacrilex gum, as demonstrated by similar blood PK parameters (tmax, Cmax, AUC). The 2 mg lozenge was found to deliver quantities of nicotine that were intermediate between those delivered by 2 and 4 mg polacrilex gum. The short-term efficacy of the 1 mg lozenge in comparison with placebo was also demonstrated with significantly more subjects continuously abstinent from smoking with active lozenges on week 6 in two different populations: moderate to heavy smokers (FTND between 4 and 7) OR = 1.72 [95% CI: 1.05-2.80]; heavy to very heavy smokers (FTND 6 and over) OR = 2.87 [95% CI: 1.18-6.97]. Nicotinell lozenges were found to be safe with mainly mild and reversible adverse events. The safety of the 1 mg lozenge formulation, even when misused was also demonstrated.

CONCLUSION

The data presented in this review demonstrate high nicotine bioavailability, excellent safety profile and proven short-term efficacy of Nicotinell lozenges. At nominal equivalent doses 1 and 2 mg Nicotinell lozenges were shown to deliver larger amounts of bioavailable nicotine compared to the nicotine polacrilex gum. According to the data developed here, the systemic exposure to nicotine could be ranked: 4 mg polacrilex gum > 2 mg Nicotinell lozenge > 1 mg Nicotinell lozenge = 2 mg polacrilex gum.Adverse events observed during the clinical trials were mild or moderate in severity, transient and completely reversible. With respect to efficacy in smoking cessation, significantly higher continuous abstinence rates were achieved with lozenge compared to placebo. In conclusion, Nicotinell lozenges offer a valuable addition to the therapeutic armamentarium available for smoking cessation.

Advice on using over-the-counter nicotine replacement therapy-patch, gum, or lozenge-to quit smoking

Although the use of over the counter (OTC) nicotine replacement therapy (NRT) is effective for smoking cessation, many concerns and misunderstandings persist that may reduce the effectiveness of NRT. Clinical practice and public health experts responded to a questionnaire that explored challenges associated with promoting proper NRT use and gathered recommendations on overcoming these challenges. Two predominant themes emerged including the identification of policies and practices that hinder NRT use, and smokers' views regarding NRT use. To address these needs, a two-part consensus statement about the use of OTC NRT to quit smoking was developed. The first part of the consensus statement identifies policy issues. The second part of the consensus statement was developed for smokers to reduce misperceptions and concerns about NRT by providing information on safety and the most effective use of NRT. The statement integrates state of the art clinical practice guidelines in a patient-centered format and presents information for policy makers to effectively support quit attempts.

Emerging pharmacotherapies for smoking cessation

PURPOSE

The neurobiology of tobacco dependence and the efficacy and safety of emerging pharmacotherapies for smoking cessation are reviewed.

SUMMARY

Dopamine is pivotal to the major addictive properties of nicotine. The neurotransmitters that influence dopamine activity include gamma-aminobutyric acid, acetylcholine, glutamate, norepinephrine, and serotonin. Opioids and endocannabinoids can also affect dopamine activity. Research on pharmacologic treatments for nicotine dependence has targeted the modulation of these neurotransmitter systems. Current pharmacotherapies for smoking cessation include bupropion and varenicline, both of which target the neurotransmitters involved in nicotine addiction. Several new therapies are emerging as possible treatment options for smoking cessation. Rimonabant, a selective cannabinoid antagonist, blocks dopamine release in the nucleus accumbens, a primary reward center for the brain. Studies have found that rimonabant may not only be effective as a smoking-cessation aid but may also assist in the maintenance of nicotine abstinence. Rimonabant has also demonstrated a weight-loss benefit, which may be attractive to smokers concerned with weight gain associated with smoking cessation. Three nicotine vaccines are currently in development, each acting to sequester nicotine from the bloodstream, thereby preventing its penetration of the central nervous system. Ongoing studies will evaluate their use as established therapies for smoking cessation. New nicotine-replacement formulations are also being developed.

CONCLUSION

There are several promising products in development targeting the mechanisms of tobacco dependence. As failure rates are high and relapse is common, these emerging therapies would offer more therapeutic options for smoking cessation and solutions to the problem of relapse.

Application of nicotine enantiomers, derivatives and analogues in therapy of neurodegenerative disorders

This review gives a brief overview over the major aspects of application of the nicotine alkaloid and its close derivatives in the therapy of some neurodegenerative disorders and diseases (e.g. Alzheimer's disease, Parkinson's disease, Tourette's syndrome, schizophrenia etc.). The issues concerning methods of nicotine analysis and isolation, and some molecular aspects of nicotine pharmacology are included. The natural and synthetic analogues of nicotine that are considered for medical practice are also mentioned. The molecular properties of two naturally occurring nicotine enantiomers are compared--the less-common but less-toxic (R)-nicotine is suggested as a natural compound that may find its place in pharmaceutical practice.

Nicotine alters the biological activities of developing mouse bone marrow-derived dendritic cells (DCs)

Cigarette smoke contains nicotine, an immunomodulatory component that is thought to affect immune surveillance and increase the progression of diseases. Dendritic cells (DCs) constitute a family of antigen-presenting (APCs) with inherent abilities to sense and translate environmental cues and to shape host immunity. We recently reported on the effects of nicotine on human DCs and proposed a possible mechanism that links cigarette smoke to higher incidences of respiratory tract infection and asthma. To establish the causal relationship between nicotine-induced DC alterations and immunomodulation in vivo, we translated our in vitro human results to the mouse system and studied the direct effects of nicotine exposure on the biological and functional properties of mouse bone marrow (BM) DCs differentiated in vitro from their precursors. We report that while the presence of nicotine in the microenvironment has no direct effect on competent mouse BM-derived DCs function, it promotes the development of mouse BM DC precursors into DCs (thereafter called nicDCs) with a semi-mature phenotype revealed by higher expression of costimulatory molecules CD80, CD86, CD40, MHC II molecules and the lymph node homing receptor, CCR7. Consistent with their maturational status, these nicDCs have reduced capacity for antigen uptake and produce substantially less Th1-promoting cytokine, IL-12, in response to Th1-polarizing adjuvant, lipopolysaccharide (LPS). Interestingly, we found that nicDCs preferentially support the proliferation and differentiation of ovalbumin (OVA)-specific naïve T cells into effector memory cells, producing significantly less IFN-gamma and more IL-4. These results provide evidence for the similarity in the effects of nicotine on mouse and human DCs, particularly the ability to modulate DC differentiation towards developing Th2 immunity.

A Nicotine Mouth Spray for Smoking Cessation: A Pilot Study of Preference, Safety and Efficacy

BACKGROUND

Various formulations of nicotine replacement therapy are commercially available.

OBJECTIVES

It was the aim of this study to test preference, safety and efficacy of a new nicotine mouth spray (1 mg/actuation; NicoNovum).

METHODS

One hundred healthy smokers wanting to quit (mean age 43.1 +/- 11.2 years) were included. They were given the mouth spray, as well as 2-mg nicotine gums and nicotine oral inhalers to try out for 1 week. Subsequently, all participants were randomized into 3 groups - mouth spray (n = 50), gum (n = 25) and inhaler (n = 25) - and treated for 3 months.

RESULTS

Fifty-four of the hundred smokers preferred the spray, compared with 28 and 18 who preferred the gum and inhaler, respectively (p < 0.01 for spray vs. both the gum and inhaler). At 6 months, the sustained abstinence rates were 8 (16%), 5 (20%) and 2 (8%) for the mouth spray, gum and inhaler, respectively (p values = n.s.). Adverse effects (AEs) were mostly drug-related local symptoms, most frequently reported at the end of the tryout period: out of 106 drug-related AEs, 90 were due to the spray, 11 and 5 to the inhaler and gum, respectively. The three most frequent AEs were almost exclusively caused by the spray: burning of the tongue/throat reported by 35, nausea by 18, and hiccup by 16 participants.

CONCLUSIONS

Participants preferred the mouth spray over the gum and inhaler, but its use was coupled with a high rate of local AEs. The efficacy of the mouth spray seemed comparable with the one obtained by the gum and inhaler. Further studies are necessary to show whether a reduction in the dose per actuation to about 0.5 mg would result in less side effects, which in turn might yield higher long-term drug compliance and possibly higher success rates than the ones achieved with other forms of nicotine replacement therapy.

Vaccination against nicotine does not prevent nicotine-induced changes in fetal nicotinic receptor binding and c-fos mRNA expression in rats

Gestational exposure of rats to nicotine produces long-lasting alterations in brain development. Vaccination of adult female rats against nicotine reduces the distribution of maternally administered nicotine to fetal brain, suggesting that vaccination might protect against these effects. In the current study, the effects of vaccination on nicotine-induced changes in fetal (3)H-epibatidine binding and c-fos mRNA expression were evaluated using tissue from a previous pharmacokinetic study of vaccination. An intermittent nicotine dosing regimen designed to resemble nicotine intake in a smoker was administered from GD1-20. Peak nicotine levels in fetal brain were reduced by vaccination, whereas the chronic accumulation of nicotine in fetal brain was not. Gestational nicotine exposure produced significant increases in (125)I-epibatidine binding to brain and spinal cord on GD20, and decreased c-fos mRNA expression in fetal striatum, adrenal and lung. Vaccination did not significantly alter these effects. These data suggest that nicotine dosing, using a clinically relevant intermittent bolus dose regimen, produces substantial changes in fetal nicotinic receptor and c-fos mRNA expression. The decrease in c-fos mRNA expression contrasts with previously reported increases, and suggests that the nicotine dosing regimen used may influence its effects. The lack of effect of vaccination suggests that the cumulative exposure of fetal tissues to nicotine may influence the measured parameters to a greater extent than peak exposure levels.

Transdermal nicotine-induced tobacco abstinence symptom suppression: nicotine dose and smokers' gender

An aversive tobacco abstinence syndrome, thought to reflect an underlying level of nicotine dependence, contributes to cigarette smokers' failed quit attempts. Nicotine replacement therapy (NRT) suppresses tobacco abstinence, but high relapse rates suggest room for improvement. Improving NRT's efficacy might begin with identifying factors that influence tobacco abstinence symptom suppression. Two such factors are smokers' gender and NRT dose. The purpose of this study was to determine the dose-related effects of transdermal nicotine (TN) on tobacco abstinence symptoms in 75 men and 53 women who regularly smoked cigarettes but who had abstained from smoking for at least 8-12 hr. Participants completed 4 double-blind, randomized 6.5-hr laboratory sessions that differed by TN dose (0, 7, 21, or 42 mg). Each session included blood sampling for plasma nicotine level, measurement of heart rate, participants' ratings of tobacco abstinence symptoms and effects of nicotine, and psychomotor performance. Increases in plasma nicotine level were related to TN dose and were independent of gender. TN-induced abstinence symptom suppression was dose-related for items assessing craving and urge to smoke and largely was independent of gender. TN increased heart rate and ratings of aversive side effects (e.g., nausea, lightheadedness) in a dose-related manner, and women were more sensitive at higher doses. Results from this laboratory study support the continued use of TN as a pharmacotherapy. Higher doses may ameliorate some abstinence symptoms, although the side effect profile, at least in the short term, may limit effectiveness, especially for women.