Lack of effects of simvastatin on smoking cessation in humans: A double-blind, randomized, placebo-controlled clinical study

Smokers with higher positive or negative urgency have lower rates of smoking cessation success 12 months after a quit attempt

Impulsivity dimensions have been shown to be associated with smoking status and tobacco use disorder severity. However, it is important to determine the specific impulsivity traits associated with smoking relapse. This study aimed at investigating the associations between impulsivity traits and smoking cessation success among adult smokers at 12 months after a quit attempt. Participants were 68 adult smokers enrolled in a 3-month course of simvastatine or placebo associated with behavioral cessation support, with a 9-month follow-up (ADDICSTATINE study). They were classified in 3 groups according to smoking status: abstinent, reduction ≥ 50%baseline or reduction < 50%baseline at 3 and 12 months. Impulsivity traits were assessed using the UPPS-P-scale. At 12 months, abstainers and participants who reduced smoking by 50% or more had significantly lower scores in negative and positive urgency compared to participants who reduced smoking by less than 50% (p = 0.011 and 0.0059). These urgency traits scores at 12 months were significantly and negatively correlated with smoking reduction at 12 months (p = 0.017 and 0.0012). These impulsivity traits were also associated with the smoking cessation success at 3 months. Patients who were abstinent at 3 months had also lower negative and positive urgency (p = 0.017 and 0.0039). Smoking cessation success at 3 and 12 months were not associated with the other impulsivity traits, sensation seeking, lack of premeditation or perseverance. Our findings suggest that positive and negative urgency are associated with smoking cessation success. Proposing better tailored-based-treatment targeting these impulsivity traits in combination with conventional treatment may help improving smoking treatment success.

Substance Addiction Rehabilitation Drugs

The relapse rate of substance abusers is high, and addiction rehabilitation adjunct drugs need to be developed urgently. There have been numerous reports on blocking the formation of substance addiction, but studies on drugs that can alleviate withdrawal symptoms are very limited. Both the dopamine transporter (DAT) hypothesis and D3 dopamine receptor (D3R) hypothesis are proposed. DAT activators reduce the extracellular dopamine level, and D3R antagonists reduce the neuron's sensitivity to dopamine, both of which may exacerbate the withdrawal symptoms subsequently. The D3R partial agonist SK608 has biased signaling properties via the G-protein-dependent pathway but did not induce D3R desensitization and, thus, may be a promising drug for the withdrawal symptoms. Drugs for serotoninergic neurons or GABAergic neurons and anti-inflammatory drugs may have auxiliary effects to addiction treatments. Drugs that promote structural synaptic plasticity are also discussed.

Environmental enrichment-inspired pharmacological tools for the treatment of addiction

Environmental enrichment (EE) has been shown to produce powerful beneficial effects in animal models of addiction. In particular, the ability of EE to promote abstinence and prevent relapse may allow for the identification of brain mechanisms responsible for the recovery from addiction. Indeed, the effects of EE on specific brain mechanisms could be mimicked by old or new molecules, which may become novel medications, called enviromimetics. Here, we review the best known enviromimetics for the treatment of addiction and suggest that, whereas these compounds may be relatively ineffective by themselves, they may be useful complements for existing therapeutic approaches to manage addiction which includes behavioural, environmental and pharmacological interventions.

Randomized Clinical Trials Investigating Innovative Interventions for Smoking Cessation in the Last Decade

Every year, billions of dollars are spent treating smoking and related conditions, yet smoking-related morbidity and mortality continue to rise. There are currently only three FDA-approved medications for smoking cessation: nicotine replacement therapy, bupropion, and varenicline. Although these medications increase abstinence rates, most individuals relapse following treatment. This chapter reviews clinical trials published within the past 10 years investigating novel smoking cessation pharmacotherapies. Among these pharmacotherapies, some showed promising results, such as cytisine and endocannabinoid modulators, whereas others failed to produce significant effects. More research is needed to develop drugs that produce higher rates of long-term abstinence and to determine which subgroups of patients benefit from a given treatment.