Extended-release bupropion: an antidepressant with a broad spectrum of therapeutic activity?

Bupropion, a noradrenaline and dopamine re-uptake inhibitor, has long been indicated for the treatment of depression. Recent studies have demonstrated additional benefits in depression, including: prevention of the recurrence of seasonal affective disorder in depressive subtypes with decreased energy, pleasure and interest; in major depression with concomitant anxiety; in elderly depressed patients; for non-response to initial serotonin re-uptake inhibitor therapy or augmentation of partial efficacy with serotonin re-uptake inhibitors; and in bipolar depression. Efficacy in other conditions has also been shown in studies of attention deficit hyperactivity disorder, nicotine dependence, obesity and hypoactive sexual desire disorder. Thus, bupropion has proven effective across a broad spectrum of depressive conditions, subtypes and comorbidities.

[Drug of the month. Varenicline (Champix)]

Smoking is responsible for 20,000 premature deaths per year in Belgium. Paradoxically, few drugs are efficient to induce tobacco cessation and to decrease relapse. Until a few weeks ago nicotin replacement therapy and bupropion only were validated in this indication. Varenicline (Champix), a partial agonist of nicotinic receptors, is a novel type of drugs currently also accepted for sale for smoking cessation. This article dwells on recent publications about efficacy of varenicline. Position, side-effects and advantages of the drug are discussed.

Intensive Smoking Cessation Intervention Reduces Mortality in High-Risk Smokers With Cardiovascular Disease

PURPOSES

To compare an intensive smoking cessation intervention against usual care in hospitalized high-risk smokers with acute cardiovascular disease.

METHODS

A total of 209 hospitalized smokers were randomized to the intensive intervention (n = 109) or to usual care (n = 100). Usual care consisted only of counseling and printed educational material provided prior to hospital discharge. Intensive treatment consisted of a minimum of 12 weeks of behavior modification counseling and individualized pharmacotherapy provided at no cost to the participant. Smoking status in all subjects was confirmed biochemically (ie, by measuring expired carbon monoxide) at 3, 6, 12, and 24 months after randomization. Outcomes included point prevalence and continuous abstinence smoking cessation rates, hospitalizations, and all-cause mortality.

RESULTS

At each follow-up interval, point prevalence and continuous abstinence smoking cessation rates were significantly greater in the intensive-treatment group compared to the usual-care group. At 24 months, continuous abstinence smoking cessation rates were 33% in the intensive-treatment group and 9% in the usual-care group (p < 0.0001). Over the 2-year follow-up period, 41 patients in the usual-care group were hospitalized compared to 25 patients in the intensive-treatment group (relative risk reduction [RRR], 44%; 95% confidence interval [CI], 16 to 63%; p = 0.007). The all-cause mortality rate was 2.8% in the intensive-treatment group and 12.0% in the usual-care group (RRR, 77%; 95% CI, 27 to 93%; p = 0.014). The absolute risk reduction in mortality was 9.2% with a number needed to treat of 11.

CONCLUSION

Hospitalized smokers, especially those with cardiovascular disease, should undergo treatment with a structured intensive cessation intervention. The duration of the initial treatment should be 3 months.

Non-Nicotinic Therapies for Smoking Cessation

Cigarette smoking is the primary cause of numerous preventable diseases; as such, the goals of smoking cessation are both to reduce health risks and to improve the quality of life. Currently, the first-line smoking cessation therapies include nicotine replacement products and bupropion. The nicotinic receptor partial agonist varenicline has recently been approved by the FDA for smoking cessation. A newer product currently under development and seeking approval by the FDA are nicotine vaccines. Clonidine and nortriptyline have demonstrated some efficacy but side effects may limit their use to second-line therapeutic products. Other therapeutic drugs that are under development include rimonabant, mecamylamine, monoamine oxidase inhibitors, and dopamine receptor D3 antagonists. Inhibitors of nicotine metabolism are also promising candidates for smoking reduction and cessation. In conclusion, promising new therapeutic products are emerging and they will provide smokers additional options to assist in achieving smoking cessation.

Varenicline: a review of its use as an aid to smoking cessation therapy

Varenicline is an orally administered alpha4beta2 nicotinic acetylcholine (ACh) receptor partial agonist. It has been approved by the US FDA (Chantix) and the European Commission (Champix) for use as an aid to smoking cessation therapy. Varenicline is an effective and generally well tolerated treatment for use in smokers who want to quit. In two well designed, phase III trials, 12 weeks' treatment with varenicline was associated with significantly higher continuous abstinence rates at weeks 9-12 than placebo or bupropion sustained-release (SR). In the longer term, continuous abstinence rates for weeks 9 through 52 demonstrated that the odds of remaining abstinent were 2.7 to 3.1 times higher with 12 weeks of varenicline treatment than with placebo; the significant difference between varenicline and bupropion SR was also maintained in the longer term in one trial. Moreover, varenicline appeared to attenuate the urge to smoke, negative affect withdrawal symptoms and the reinforcing effects of smoking. Among those achieving abstinence, an additional 12 weeks of varenicline therapy helped increase the likelihood of long-term abstinence. Thus, varenicline is a valuable new agent for use as an aid to smoking cessation treatment.

Clinical Efficacy of Citalopram Alone or Augmented with Bupropion in Methadone-Stabilized Patients

Despite the success of opiate-agonist therapies such as methadone for the treatment of opiate addiction, treatment response is not complete. This study evaluates the efficacy of citalopram augmented with bupropion in the treatment of illicit opiate use in a methadone-stabilized population. We conducted a 12-week randomized, double-blind, outpatient clinical trial in which 60 subjects were randomized into one of three treatment groups: placebo, citalopram (40 mg/day) plus placebo, or citalopram (40 mg/day) plus bupropion (50 mg/day). The results indicate that neither citalopram nor citalopram augmented with bupropion were more effective than placebo in the treatment of opioid abuse.

Catechol-O-methyltransferase (COMT) gene variants predict response to bupropion therapy for tobacco dependence

BACKGROUND

Although bupropion is efficacious for smoking cessation, only a minority of smokers are able to quit. Pharmacogenetic research may improve treatment outcomes through discovery of DNA sequences predictive of successful pharmacotherapy for subgroups of smokers. We investigated variants in the catechol-O-methyltransferase (COMT) gene in a smoking cessation trial of bupropion.

METHODS

A double-blind, placebo-controlled, 10-week trial of bupropion and counseling (with a 6-month follow-up period) was conducted at two university-based smoking cessation research programs. Abstinence was biochemically verified at the end of treatment and at 6 months after the target quit date.

RESULTS

At the end of the treatment phase, statistically significant interaction effects indicated that COMT haplotypes of two SNPs (rs737865 and rs165599) predicted the efficacy of bupropion compared with placebo. This interaction effect was attenuated at 6-month follow-up.

CONCLUSIONS

COMT haplotypes at rs737865 and rs165599 may predict a favorable outcome for bupropion treatment for smoking cessation. European-American smokers with a G allele at both SNPs may not benefit from bupropion treatment. Small numbers of some COMT haplotypes limit interpretation of response. If study findings are confirmed in additional large studies, COMT genotyping could be applied to identify likely responders to bupropion treatment for smoking cessation.

Restless legs syndrome induced by citalopram: a psychiatric emergency?

OBJECTIVE

The objective of this case report is to create awareness on restless legs syndrome (RLS) among clinicians working in emergency units.

METHOD

We describe a case reporting important aggravation of RLS associated with citalopram, 60 mg/day, in a 48-year-old woman who was sent to the emergency unit by her general practitioner. Citalopram was replaced by bupropion, 150 mg/day, and sertraline, 50 mg/day.

RESULTS

Three days later, symptoms of RLS started to diminish and, after 3 weeks, clinical symptoms had disappeared entirely. On 6-month follow-up, the patient did not manifest clinically significant RLS. Ignoring RLS could lead to a worsening of symptoms and could increase the risk for iatrogenic conditions. The prevalence of RLS in the general population is 3-9%; nevertheless, this syndrome is frequently underdiagnosed.

CONCLUSION

This case report suggests that RLS could be considered as a possible "dopamine-dependent side effect" of selective serotonin reuptake inhibitors (SSRIs). Bupropion could potentially "correct" dopaminergic dysfunction in RLS, and sertraline appears to be the SSRI that provides the least risk of RLS by blocking dopamine reuptake.

[Pharmacotherapy of adult Attention Deficit/Hyperactivity Disorder (ADHD): a systematic review]

INTRODUCTION

Attention Deficit/Hyperactivity Disorder (ADHD) is one of the most prevalent psychiatric disorders of childhood, which persists into adulthood in 10-60% of the cases. A growing body of data suggests that pharmacotherapy of the disorder is efficacious but a comprehensive summary of available evidence from clinical trials is lacking. The aim of the article was to provide a systematic review of therapeutic efficacy observed in the pharmacological treatment of ADHD based on data from controlled clinical trials.

METHODS

We used the search engines PubMed and Medline to identify relevant clinical trials. Studies with short term, double-blind and parallel design were selected for the review.

RESULTS

Altogether, 11 trials were included in the review. Our systematic review indicated that adult ADHD is treated with the same medications as the childhood form of the disorder, including psychostimulants as the first line of treatment, antidepressants as the second line, and more recently atomoxetine as well. In view of the fact that only relatively few investigations were available within the individual drug classes, no statistically significant differences could be demonstrated among the classes; thus, our data with regard to effect size should only be considered as descriptive. Most of the investigations focused on psychostimulants, which produced a strong effect size vs. placebo. With regard to atomoxetine, only a few studies were found, in which, however, a large number of subjects were enrolled, representing the largest studies in the literature. The effect size of atomoxetine in these studies was in the medium range. This result is noteworthy since the average age of the subjects in these studies was the highest among the selected studies (more than 40 years, in contrast to less than 40 years in all other studies); this (considering the chronicity of the illness) is viewed as a predictor of poor therapeutic response. Among antidepressants, most clinical trials tested bupropion; based on these trials, this compound is expected to produce an effect size in the medium range.

CONCLUSIONS

Pharmacologic agents affecting the dopamine and norepinephrine system have been found to be effective in reducing the symptoms of adult ADHD. In half of the trials, the tested drug was a psychostimulant. The effect sizes of the studies with amphetamine, methylphenidate and dexmethylphenidate were in the high effect size range, and owing to the small number of investigations, we could not discriminate between these drugs. Based on the data available from the literature, non-stimulant medications are indicated when substance dependence or abuse is in the history, or when the side effects of psychostimulants are not tolerated by the patient.

D2-like dopamine receptors mediate the response to amphetamine in a mouse model of ADHD

The mechanisms underlying the effects of psychostimulants in attention deficit hyperactivity disorder (ADHD) are not well understood, but indirect evidence implicates D2 dopamine receptors. Here we dissect the components of dopaminergic neurotransmission in the hyperactive mouse mutant coloboma to identify pre- and postsynaptic elements essential for the effects of amphetamine in these mice. Amphetamine treatment reduced locomotor activity in coloboma mice, but induced a robust increase in dopamine overflow suggesting that abnormal regulation of dopamine efflux does not account for the behavioral effect. However, the D2-like dopamine receptor antagonists haloperidol and raclopride, but not the D1-like dopamine receptor antagonist SCH23390, blocked the amphetamine-induced reduction in locomotor activity in coloboma mice, providing direct evidence that D2-like dopamine receptors mediate the effect of amphetamine in these mice. With the precedent established that it is possible to directly antagonize this response, this strategy should prove useful for identifying novel therapeutics in ADHD.

Resolution of sleepiness and fatigue in major depressive disorder: A comparison of bupropion and the selective serotonin reuptake inhibitors

BACKGROUND

The purpose of this study was to examine whether the treatment of major depressive disorder (MDD) with the norepinephrine-dopamine reuptake inhibitor (NDRI) bupropion results in a greater resolution of sleepiness and fatigue than with the selective serotonin reuptake inhibitors (SSRIs).

METHODS

Six double-blind, randomized clinical trials comparing bupropion (n = 662) with an SSRI (n = 655) for the treatment of MDD were pooled. Hypersomnia scores were defined as the sum of scores of the Hamilton Depression Rating Scale (HDRS) items #22, 23, and 24. Fatigue scores were defined as the score of HDRS item #13.

RESULTS

There was a greater improvement in hypersomnia scores among bupropion-treated than SSRI-treated (p < .0001) or placebo-treated patients (p = .0008). There was also a greater improvement in fatigue scores among bupropion-treated (p < .0001) and SSRI-treated (p = .0005) than placebo-treated patients as well as a greater improvement in fatigue scores among bupropion-treated than SSRI-treated patients (p = .0078). Fewer bupropion-remitters than SSRI-remitters experienced residual hypersomnia (20.5% vs. 32.1%; p = .0014) or residual fatigue (19.5% vs. 30.2%; p = .0020).

CONCLUSION

Treatment of MDD with the NDRI bupropion resulted in a greater resolution of sleepiness and fatigue than SSRIs treatment. Although preliminary, these results warrant prospectively designed studies examining potential differences between bupropion and the SSRIs on these specific depressive symptoms.

Absence of association with DAT1 polymorphism and response to methylphenidate in a sample of adults with ADHD

A polymorphism in the dopamine transporter gene (DAT1) has been previously associated with ADHD and methylphenidate has been hypothesized to block the dopamine transporter. The goal of this study was to examine whether a 40-bp variable number of tandem repeats (VNTR) of DAT1 moderate response and adverse effects associated with methylphenidate treatment of adults with ADHD. Subjects were 106 adults with ADHD enrolled in 6-week randomized placebo-controlled parallel design trials of methylphenidate (OROS and immediate release preparations). There was no evidence of an association between DAT1 VNTR and response to methylphenidate (F(2,100) = 0.04, P = 0.9). Similarly, there was no pattern of statistically significant association with DAT1 VNTR and cardiovascular or spontaneously reported adverse effects. We failed to identify an association with DAT1 and the response or tolerability of methylphenidate in adults with ADHD.

Looking for boomerang effects: a pre-post experimental study of the effects of exposure of youth to television advertising for nicotine replacement therapy and Zyban

In the context of concerns about unintended "boomerang" influences of advertising, this study aimed to examine effects of nicotine replacement therapy (NRT) and Zyban advertising on youth perceptions of the ease of quitting, health risks of smoking and future intentions to smoke. 718 youth aged 14-16years were randomly allocated to view four television ads promoting either: NRT; Zyban; non-pharmaceutical cessation services (telephone Quitline); or non-cessation messages on sun protection. Questionnaire measures were administered before and after viewing ads. There were no effects of advertising exposure on perceived health effects of smoking or intentions to smoke. Compared with the sun protection ads, but not the Quitline ads, those exposed to NRT ads reported stronger perceptions about the ease of quitting, but non-susceptible non-smokers primarily drove this difference. This study suggests that exposure to NRT and Zyban advertising in an experimental context does not reliably influence youth smoking-related beliefs, especially those vulnerable to becoming regular smokers.

Preadolescent methylphenidate versus cocaine treatment differ in the expression of cocaine-induced locomotor sensitization during adolescence and adulthood

BACKGROUND

Methylphenidate (MPH), the most commonly prescribed medication for childhood attention-deficit/hyperactivity disorder (ADHD), shares chemical and mechanistic similarities to cocaine which has stimulated research to address the addiction liability following treatment.

METHODS

Utilizing locomotor sensitization we examined the consequences of recurrent MPH versus cocaine treatment during preadolescence in altering cocaine-induced locomotor behavior in adolescent and adult mice. Black Swiss Webster mice were treated with MPH, cocaine, or saline during preadolescence. To test whether MPH pretreatment during preadolescence contributed to an altered sensitivity to cocaine during adolescence, these mice were treated with recurrent cocaine or saline during adolescence. All mice were challenged with cocaine as adults.

RESULTS

Recurrent MPH treatment, unlike cocaine treatment in preadolescent mice, had no effect on locomotor sensitization to cocaine during adolescence or adulthood, as compared with saline controls. Furthermore, unlike cocaine, administration of MPH in adolescence did not augment the response to cocaine challenge.

CONCLUSIONS

MPH treatment during preadolescence does not increase subsequent sensitivity to cocaine, whereas cocaine treatment does. Thus, MPH treatment during preadolescence does not appear to persistently induce long-term adaptations, which may underlie an enhanced liability for subsequent drug abuse.

Plasticity

Over the past 20 years, evidence has mounted regarding the capacity of the central nervous system to alter its structure and function throughout life. Injury to the central nervous system appears to be a particularly potent trigger for plastic mechanisms to be elicited. Following focal injury, widespread neurophysiological and neuroanatomical changes occur both in the peri-infarct region, as well as throughout the ipsi- and contralesional cortex, in a complex, time-dependent cascade. Since such post-injury plasticity can be both adaptive or maladaptive, current research is directed at understanding how plasticity may be modulated to develop more effective therapeutic interventions for neurological disorders, such as stroke. Behavioral training appears to be a significant contributor to adaptive plasticity after injury, providing a neuroscientific foundation for the development of physical therapeutic approaches. Adjuvant therapies, such as pharmacological agents and exogenous electrical stimulation, may provide a more receptive environment through which behavioral therapies may be imparted. This chapter reviews some of the recent results from animal models of injury and recovery that depict the complex time course of plasticity following cortical injury and implications for neurorehabilitation.

Spirometry and smoking cessation advice in general practice: A randomised clinical trial

RATIONALE

To assess the success rate of smoking cessation with the "minimal intervention strategy" in general practice, and to determine the influence of spirometry on this success rate.

METHODS

Training in smoking cessation advice was given to 16 general practitioners (GPs). During 12 weeks, these GPs screened their practice population for smoking habits, the degree of dependence on nicotine, and the motivation to quit smoking. Patients willing to stop were randomised to a group that underwent a single office spirometry, or to a control group. The GPs were asked to support the attempts with the minimal intervention strategy. Success rates were compared after 6, 12 and 24 months.

RESULTS

On a population of 5590 patients, 1206 smokers were identified (22%). To the vulnerable group, identified following the Prochaska and Di Clemente scheme, the proposal was made to change smoking behaviour. Two hundred and twenty-one patients undertook an attempt of smoking cessation. Nicotine replacement therapy (NRT) or bupropion was prescribed in 51% of the attempts. Sixty-four sustained quitters were counted after 6 months (29%), 43 after 1 year (19%) and 33 after 2 years (15%). We found a small but statistically non-significant difference in success rate in favour of the group that underwent office spirometry.

CONCLUSION

GPs can motivate almost 20% of their smoking population to quit smoking. The success rate with the minimal intervention strategy was 19% after 1 year and 15% after 2 years. We found no arguments in favour of confronting smokers with their lung function as a tool for enhancing smoking cessation.

Smoking Cessation Efficacy and Safety of Varenicline, an α4β2 Nicotinic Receptor Partial Agonist

BACKGROUND

Varenicline, an alpha4beta2 nicotinic receptor partial agonist, has the potential to relieve nicotine craving and withdrawal symptoms while reducing the reinforcing effects of nicotine. Phase 3 studies have evaluated the effects of varenicline on inducing smoking cessation and maintaining smoking abstinence.

SUBJECTS AND METHODS

Two identically designed randomized, double-blind, smoking cessation studies recruited smokers of 10 or more cigarettes daily who were motivated to quit. Treatment with varenicline 1 mg twice daily was compared with treatment with bupropion 150 mg twice daily or matching placebo for 12 weeks, followed by a 40-week nontreatment observation period. In a third study that investigated maintenance of abstinence, smokers were treated with 12 weeks of open-label varenicline 1 mg twice daily. Subjects who did not smoke during the last week of treatment were eligible to be randomized to varenicline or placebo for an additional 12 weeks, followed by a 28-week nontreatment observation period. Brief smoking cessation counseling was given at clinic visits or telephone contacts scheduled regularly during the entire duration of the 3 studies. Measurement of carbon monoxide in expired breath was used to verify the subjects' reports of nonsmoking.

RESULTS

In the 2 smoking cessation studies, varenicline significantly increased the 4-week continuous abstinence rate during weeks 9 to 12 relative to placebo and bupropion. The continuous abstinence rate during weeks 9 to 52 was also increased compared with placebo and with bupropion (statistically significant in one of the studies). In the maintenance study, smokers who quit after an initial course of open-label varenicline had greater long-term efficacy when they received an additional 12 weeks of varenicline than when they received placebo. In all 3 studies, varenicline was safe and well tolerated, with overall treatment discontinuation rates similar to that of placebo. Nausea was the adverse event that occurred more frequently in subjects receiving varenicline but was mostly mild in intensity.

CONCLUSION

The results of these studies demonstrate a new order of efficacy in medical therapy for smoking cessation. Varenicline proved to be more effective than bupropion in inducing cessation. Furthermore, varenicline prevented relapse in smokers who had progressed toward cessation by quitting for at least 1 week.

No evidence for a major role of polymorphisms during bupropion treatment

This study evaluated the ability of polymorphisms in five candidate genes to predict weight gain among patients taking bupropion or placebo in a smoking cessation trial. Five hundred fifty-three smokers were enrolled into a randomized double-blind, placebo-controlled trial and followed for 12 months. Five candidate genes [DRD2 Taq1 (rs1800497), DRD2-141 (rs1799732), C957T (rs6277), COMT (rs4818), and SLC6A3] were genotyped. Weights at baseline, at end of treatment, and after 6 and 12 months of follow-up were self-reported. Smoking abstinence at each endpoint was self-reported and confirmed biochemically. A self-reported average weight gain after 12 months of 1.1 +/- 6.0 kg (mean +/- standard deviation) in the bupropion group and 1.8 +/- 4.8 kg in the placebo group was noted. For subjects with biochemically confirmed abstinence from smoking, the HL genotype (alleles coding Val at codon 108 are denoted as H, and those coding Met are denoted as L) at the COMT locus and A1A1 genotype at the DRD2 Taq1 locus were associated with less weight gain at the end of treatment. The TC genotype at the C957T locus was associated with increased weight gain at 6 months of follow-up. However, no polymorphisms or their interactions with bupropion consistently and significantly predicted baseline BMI or weight change during treatment for all study subjects. Overall, our results do not support a major role for these five candidate genes in weight gain after smoking cessation.

Bupropion in Atopic Dermatitis

Bupropion is an antidepressive drug whose main mechanism of action seems to be the inhibition of noradrenaline and dopamine recapture. We present a clinical case of a 50-year-old person with severe atopic dermatitis (A.D.) and without psychiatric symptoms associated, who was casually treated with bupropion with very good results. The mechanisms of action are not yet known, given the diversity of the implied physiopathology mechanisms: genetic, immunological, inflammatory, etc. The use of bupropion in serious and resistant cases to other treatments could constitute a pertinent therapeutic alternative.

[An integrative approach of attention deficit in adolescence]

The present work intends to embrace all the areas where the dysfunction for deficit of attention (ADHD) it is expressed along the life of a adolescent and the impact that this has in its development, and in the family. Many times it was to only understand this square for their impacts in the curricular environment, but this syndrome impacts a lot beyond the school of a youth, it is in and of itself that the boarding will be enlarged to all those areas where a decisive commitment is presented.

Dexmethylphenidate extended release: in attention-deficit hyperactivity disorder

Dexmethylphenidate extended release (XR) is an orally administered, bimodal release, capsule formulation of the active d-enantiomer of methylphenidate (MPH), which inhibits dopamine and norepinephrine (noradrenaline) reuptake to increase their concentration in the extraneuronal space. A single dose of dexmethylphenidate XR mimics the pharmacokinetic profile of two doses of dexmethylphenidate immediate-release formulation administered 4 hours apart, albeit with less fluctuation in plasma concentration. Once-daily dexmethylphenidate XR was more effective than placebo in reducing attention-deficit hyperactivity disorder (ADHD) symptom scores in children, adolescents and adults with ADHD in four randomised, double-blind, placebo-controlled trials of up to 7 weeks' duration. In crossover trials in children (aged 6-12 years), dexmethylphenidate XR 20 mg/day reduced mean ADHD symptom scores 1 hour after administration (by 43% in one trial) and was significantly better than placebo for up to 12 hours. Dexmethylphenidate XR 5-30 mg/day reduced mean ADHD symptom scores by 49%, while scores declined by 16% with placebo in a 7-week trial in children and adolescents (aged 6-17 years). Dexmethylphenidate XR 20, 30 or 40 mg/day reduced ADHD symptom scores by 36-46% versus a 21% reduction with placebo in a 5-week trial in adults (aged 18-60 years). Dexmethylphenidate XR was generally well tolerated in children, adolescents and adults with ADHD, with an adverse-event profile typical of MPH.