Comparing topiramate with naltrexone in the treatment of alcohol dependence

Glutamate-Mediated Excitotoxicity in the Pathogenesis and Treatment of Neurodevelopmental and Adult Mental Disorders

Glutamate is the main excitatory neurotransmitter in the brain wherein it controls cognitive functional domains and mood. Indeed, brain areas involved in memory formation and consolidation as well as in fear and emotional processing, such as the hippocampus, prefrontal cortex, and amygdala, are predominantly glutamatergic. To ensure the physiological activity of the brain, glutamatergic transmission is finely tuned at synaptic sites. Disruption of the mechanisms responsible for glutamate homeostasis may result in the accumulation of excessive glutamate levels, which in turn leads to increased calcium levels, mitochondrial abnormalities, oxidative stress, and eventually cell atrophy and death. This condition is known as glutamate-induced excitotoxicity and is considered as a pathogenic mechanism in several diseases of the central nervous system, including neurodevelopmental, substance abuse, and psychiatric disorders. On the other hand, these disorders share neuroplasticity impairments in glutamatergic brain areas, which are accompanied by structural remodeling of glutamatergic neurons. In the current narrative review, we will summarize the role of glutamate-induced excitotoxicity in both the pathophysiology and therapeutic interventions of neurodevelopmental and adult mental diseases with a focus on autism spectrum disorders, substance abuse, and psychiatric disorders. Indeed, glutamatergic drugs are under preclinical and clinical development for the treatment of different mental diseases that share glutamatergic neuroplasticity dysfunctions. Although clinical evidence is still limited and more studies are required, the regulation of glutamate homeostasis is attracting attention as a potential crucial target for the control of brain diseases.

Topiramate Versus Naltrexone for Alcohol Use Disorder: A Genotype-Stratified Double-Blind Randomized Controlled Trial

OBJECTIVE

There have been no well-controlled and well-powered comparative trials of topiramate with other pharmacotherapies for alcohol use disorder (AUD), such as naltrexone. Moreover, the literature is mixed on the effects of two polymorphisms-rs2832407 (in GRIK1) and rs1799971 (in OPRM1)-on response to topiramate and naltrexone, respectively. The authors sought to examine the comparative effectiveness of topiramate and naltrexone in improving outcomes in AUD and to examine the role of the rs2832407 and rs1799971 polymorphisms, respectively, on response to these medications.

METHODS

In a 12-week, double-blind, placebo-controlled, randomized, multisite, genotype-stratified (rs2832407 and rs1799971) clinical trial comparing topiramate and naltrexone in treating AUD, 147 patients with AUD were randomly assigned to treatment with topiramate or naltrexone, stratified by genotype (rs2832407*CC and *AC/AA genotypes and rs1799971*AA and *AG/GG genotypes). The predefined primary outcome was number of heavy drinking days per week. Predefined secondary outcomes included standard drinks per drinking day per week, body mass index (BMI), craving, markers of liver injury, mood, and adverse events.

RESULTS

For the number of heavy drinking days per week, there was a near-significant time-by-treatment interaction. For the number of standard drinks per drinking day per week, there was a significant time-by-treatment interaction, which favored topiramate. There were significant time-by-treatment effects, with greater reductions observed with topiramate than naltrexone for BMI, craving, and gamma-glutamyltransferase level. Withdrawal due to side effects occurred in 8% and 5% of the topiramate and naltrexone groups, respectively. Neither polymorphism showed an effect on treatment response.

CONCLUSIONS

Topiramate is at least as effective and safe as the first-line medication, naltrexone, in reducing heavy alcohol consumption, and superior in reducing some clinical outcomes. Neither rs2832407 nor rs1799971 had effects on topiramate and naltrexone treatments, respectively.

Anticonvulsant Classes and Possible Mechanism of Actions

Epilepsy is considered one of the most common neurological disorders worldwide; it needs long-term or life-long treatment. Despite the presence of several novel antiepileptic drugs, approximately 30% patients still suffer from drug-resistant epilepsy. Subsequently, searching for new anticonvulsants with lower toxicity and better efficacy is still in paramount demand. Using target-based studies in the discovery of novel antiepileptics is uncommon owing to the insufficient information on the molecular pathway of epilepsy and complex mode of action for most of known antiepileptic drugs. In this review, we investigated the properties of anticonvulsants, types of epileptic seizures, and mechanism of action for anticonvulsants.

A Review of the Characteristics of Clinical Trials and Potential Medications for Alcohol Dependence: Data Analysis from ClinicalTrials.gov

Objective. This study provides a comprehensive analysis of the characteristics of clinical trials related to alcohol dependence that are registered on ClinicalTrials.gov. Methods. All ClinicalTrials.gov trials registered up to 1 January 2023 were examined, focusing on trials that involved alcohol dependence. All 1295 trials were summarized by presenting their characteristics and results and reviewed most intervention drugs used in the treatment of alcohol dependence. Results. The study analysis identified a total of 1295 clinical trials registered on ClinicalTrials.gov that were focused on alcohol dependence. Of these, 766 trials had been completed, representing 59.15% of the total, while 230 trials were currently recruiting participants, accounting for 17.76% of the total. None of the trials had yet been approved for marketing. The majority of the studies included in this analysis were interventional studies (1145 trials, or 88.41%), which accounted for most of the patients enrolled in the trials. In contrast, observational studies represented only a small portion of the trials (150 studies, or 11.58%) and involved a smaller number of patients. In terms of geographic distribution, the majority of registered studies were located in North America (876 studies, or 67.64%), while only a small number of studies were registered in South America (7 studies, or 0.54%). Conclusions. The purpose of this review is to provide a basis for the treatment of alcohol dependence and prevention of its onset through an overview of clinical trials registered at ClinicalTrials.gov. It also offers essential information for future research to guide future studies.

Drug Addiction and Incarceration: A Call for Research and Transparency Among Prison-Based Substance Abuse Treatment Programs

As drug-related offense and illicit drug overdose rates continue to grow in the United States, criminologists have begun to pay more attention to factors influencing illicit drug use as well as effective methods of promoting drug abstinence in treatment programs across the nation. Although much scholarly attention is given to community-based substance abuse treatment programs, a considerably smaller focus of research is devoted to substance abuse treatment programs that are prison-based. Moreover, some of the most effective methods of treating inmates who are addicted to an illicit drug (such as Cognitive Behavioral Therapy, Therapeutic Community, etc.), although praised for their initiative and theoretical effectiveness, are often demonstrated via individualized empirical study that the expected advantages of such programmatic forms of treatment fail to emerge. The present study explores what scholars have discovered regarding the effectiveness of prison-based substance abuse treatment programs, how such findings appear to contradict one another, and why state prison systems should be more transparent regarding their in-house drug treatment programs in their publicly accessible reports that are formulated into cumulative reports on each states' Bureau of Corrections websites.

Psychosocial and pharmacologic interventions to reduce harmful alcohol use in low- and middle-income countries

BACKGROUND

Harmful alcohol use is defined as unhealthy alcohol use that results in adverse physical, psychological, social, or societal consequences and is among the leading risk factors for disease, disability and premature mortality globally. The burden of harmful alcohol use is increasing in low- and middle-income countries (LMICs) and there remains a large unmet need for indicated prevention and treatment interventions to reduce harmful alcohol use in these settings. Evidence regarding which interventions are effective and feasible for addressing harmful and other patterns of unhealthy alcohol use in LMICs is limited, which contributes to this gap in services.

OBJECTIVES

To assess the efficacy and safety of psychosocial and pharmacologic treatment and indicated prevention interventions compared with control conditions (wait list, placebo, no treatment, standard care, or active control condition) aimed at reducing harmful alcohol use in LMICs.

SEARCH METHODS

We searched for randomized controlled trials (RCTs) indexed in the Cochrane Drugs and Alcohol Group (CDAG) Specialized Register, the Cochrane Clinical Register of Controlled Trials (CENTRAL) in the Cochrane Library, PubMed, Embase, PsycINFO, CINAHL, and the Latin American and Caribbean Health Sciences Literature (LILACS) through 12 December 2021. We searched clinicaltrials.gov, the World Health Organization International Clinical Trials Registry Platform, Web of Science, and Opengrey database to identify unpublished or ongoing studies. We searched the reference lists of included studies and relevant review articles for eligible studies.

SELECTION CRITERIA

All RCTs comparing an indicated prevention or treatment intervention (pharmacologic or psychosocial) versus a control condition for people with harmful alcohol use in LMICs were included.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 66 RCTs with 17,626 participants. Sixty-two of these trials contributed to the meta-analysis. Sixty-three studies were conducted in middle-income countries (MICs), and the remaining three studies were conducted in low-income countries (LICs). Twenty-five trials exclusively enrolled participants with alcohol use disorder. The remaining 51 trials enrolled participants with harmful alcohol use, some of which included both cases of alcohol use disorder and people reporting hazardous alcohol use patterns that did not meet criteria for disorder. Fifty-two RCTs assessed the efficacy of psychosocial interventions; 27 were brief interventions primarily based on motivational interviewing and were compared to brief advice, information, or assessment only. We are uncertain whether a reduction in harmful alcohol use is attributable to brief interventions given the high levels of heterogeneity among included studies (Studies reporting continuous outcomes: Tau² = 0.15, Q =139.64, df =16, P<.001, I² = 89%, 3913 participants, 17 trials, very low certainty; Studies reporting dichotomous outcomes: Tau²=0.18, Q=58.26, df=3, P<.001, I² =95%, 1349 participants, 4 trials, very low certainty). The other types of psychosocial interventions included a range of therapeutic approaches such as behavioral risk reduction, cognitive-behavioral therapy, contingency management, rational emotive therapy, and relapse prevention. These interventions were most commonly compared to usual care involving varying combinations of psychoeducation, counseling, and pharmacotherapy. We are uncertain whether a reduction in harmful alcohol use is attributable to psychosocial treatments due to high levels of heterogeneity among included studies (Heterogeneity: Tau² = 1.15; Q = 444.32, df = 11, P<.001; I²=98%, 2106 participants, 12 trials, very low certainty). Eight trials compared combined pharmacologic and psychosocial interventions with placebo, psychosocial intervention alone, or another pharmacologic treatment. The active pharmacologic study conditions included disulfiram, naltrexone, ondansetron, or topiramate. The psychosocial components of these interventions included counseling, encouragement to attend Alcoholics Anonymous, motivational interviewing, brief cognitive-behavioral therapy, or other psychotherapy (not specified). Analysis of studies comparing a combined pharmacologic and psychosocial intervention to psychosocial intervention alone found that the combined approach may be associated with a greater reduction in harmful alcohol use (standardized mean difference (standardized mean difference (SMD))=-0.43, 95% confidence interval (CI): -0.61 to -0.24; 475 participants; 4 trials; low certainty). Four trials compared pharmacologic intervention alone with placebo and three with another pharmacotherapy. Drugs assessed were: acamprosate, amitriptyline, baclofen disulfiram, gabapentin, mirtazapine, and naltrexone. None of these trials evaluated the primary clinical outcome of interest, harmful alcohol use.   Thirty-one trials reported rates of retention in the intervention. Meta-analyses revealed that rates of retention between study conditions did not differ in any of the comparisons (pharmacologic risk ratio (RR) = 1.13, 95% CI: 0.89 to 1.44, 247 participants, 3 trials, low certainty; pharmacologic in addition to psychosocial intervention: RR = 1.15, 95% CI: 0.95 to 1.40, 363 participants, 3 trials, moderate certainty). Due to high levels of heterogeneity, we did not calculate pooled estimates comparing retention in brief (Heterogeneity: Tau² = 0.00; Q = 172.59, df = 11, P<.001; I2 = 94%; 5380 participants; 12 trials, very low certainty) or other psychosocial interventions (Heterogeneity: Tau² = 0.01; Q = 34.07, df = 8, P<.001; I2 = 77%; 1664 participants; 9 trials, very low certainty). Two pharmacologic trials and three combined pharmacologic and psychosocial trials reported on side effects. These studies found more side effects attributable to amitriptyline relative to mirtazapine, naltrexone and topiramate relative to placebo, yet no differences in side effects between placebo and either acamprosate or ondansetron. Across all intervention types there was substantial risk of bias. Primary threats to validity included lack of blinding and differential/high rates of attrition.

AUTHORS' CONCLUSIONS

In LMICs there is low-certainty evidence supporting the efficacy of combined psychosocial and pharmacologic interventions on reducing harmful alcohol use relative to psychosocial interventions alone. There is insufficient evidence to determine the efficacy of pharmacologic or psychosocial interventions on reducing harmful alcohol use largely due to the substantial heterogeneity in outcomes, comparisons, and interventions that precluded pooling of these data in meta-analyses. The majority of studies are brief interventions, primarily among men, and using measures that have not been validated in the target population. Confidence in these results is reduced by the risk of bias and significant heterogeneity among studies as well as the heterogeneity of results on different outcome measures within studies. More evidence on the efficacy of pharmacologic interventions, specific types of psychosocial interventions are needed to increase the certainty of these results.

A Bayesian meta-analysis of topiramate's effectiveness for individuals with alcohol use disorder

BACKGROUND

Topiramate (TPM) has the potential to become one of the most prominent treatment options for alcohol use disorder (AUD). We investigated the efficacy of TPM for AUD treatment, considering new randomized controlled trials carried out since the publication of four prior investigations.

METHODS

We searched six major databases, comparing TPM to placebo for AUD treatment. We performed a Bayesian meta-analysis. We conducted a meta-regression, analyzing the effect of age, TPM dosage, duration of treatment, gender, and attrition rate on the outcomes measured. The protocol is registered with PROSPERO: CRD42021286266.

RESULTS

TPM reduced heavy drinking days (d = 0.401, Bayes factor (BF) = 23.088) and weeks (d = 0.461, BF = 3.784), lowered alcohol craving (d = 0.477, BF = 107.749), prolonged abstinence throughout the duration of trials (d = 0.505, BF = 54.998), and decreased the amount of gamma-glutamyl transferase in the blood (d = 0.345, BF = 39.048). The analysis pointed out that TPM could reduce anxiety (d = 0.517, BF = 5.993). TPM's efficacy in relieving alcohol withdrawal, minimizing relapse, and decreasing depressive symptoms was inconclusive. There was evidence of a meta-regression effect of attrition rate on heavy drinking days and craving and length of treatment on abstinence.

CONCLUSION

TPM has the potential to become a key pharmacological agent in the treatment of AUD.

Developing and Implementing a Web-Based Relapse Prevention Psychotherapy Program for Patients With Alcohol Use Disorder: Protocol for a Randomized Controlled Trial

BACKGROUND

 Alcohol use disorder (AUD) is characterized by problematic alcohol use accompanied by clinically substantial distress. Patients with AUD frequently experience high relapse rates, and only 1 in 5 remain abstinent 12 months post treatment. Traditional face-to-face relapse prevention therapy (RPT) is a form of cognitive behavioral therapy (CBT) that examines one's situational triggers, maladaptive thought processes, self-efficacy, and motivation. However, access to this treatment is frequently limited due to its high cost, long waitlists, and inaccessibility. A web-based adaptation of RPT (e-RPT) could address these limitations by providing a more cost-effective and accessible delivery method for mental health care in this population.

OBJECTIVE

 This study protocol aims to establish the first academic e-RPT program to address AUD in the general population. The primary objective of this study is to compare the efficacy of e-RPT to face-to-face RPT in decreasing relapse rates. The secondary objective is to assess the effects of e-RPT on quality of life, self-efficacy, resilience, and depressive symptomatology. The tertiary objective is to evaluate the cost-effectiveness of e-RPT compared to face-to-face RPT.

METHODS

 Adult participants (n=60) with a confirmed diagnosis of AUD will be randomly assigned to receive 10 sessions of e-RPT or face-to-face RPT. e-RPT will consist of 10 predesigned modules and homework with asynchronous, personalized feedback from a therapist. Face-to-face RPT will comprise 10 one-hour face-to-face sessions with a therapist. The predesigned modules and the face-to-face sessions will present the same content and structure. Self-efficacy, resilience, depressive symptomatology, and alcohol consumption will be measured through various questionnaires at baseline, amid treatment, and at the end of treatment.

RESULTS

 Participant recruitment is expected to begin in October 2022 through targeted advertisements and physician referrals. Completed data collection and analysis are expected to conclude by October 2023. Outcome data will be assessed using linear and binomial regression (for continuous and categorical outcomes, respectively). Qualitative data will be analyzed using thematic analysis methods.

CONCLUSIONS

 This study will be the first to examine the effectiveness of e-RPT compared to face-to-face RPT. It is posited that web-based care can present benefits in terms of accessibility and affordability compared to traditional face-to-face psychotherapy.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05579210; https://clinicaltrials.gov/ct2/show/NCT05579210.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/44694.

Closing the treatment gap for alcohol use disorders in low- and middle-income countries

The alcohol-attributable disease burden is greater in low- and middle-income countries (LMICs) as compared to high-income countries. Despite the effectiveness of interventions such as health promotion and education, brief interventions, psychological treatments, family-focused interventions, and biomedical treatments, access to evidence-based care for alcohol use disorders (AUDs) in LMICs is limited. This can be explained by poor access to general health and mental health care, limited availability of relevant clinical skills among health care providers, lack of political will and/or financial resources, historical stigma and discrimination against people with AUDs, and poor planning and implementation of policies. Access to care for AUDs in LMICs could be improved through evidence-based strategies such as designing innovative, local and culturally acceptable solutions, health system strengthening by adopting a collaborative stepped care approach, horizontal integration of care into existing models of care (e.g., HIV care), task sharing to optimise limited human resources, working with families of individuals with AUD, and leveraging technology-enabled interventions. Moving ahead, research, policy and practice in LMICs need to focus on evidence-based decision-making, responsiveness to context and culture, working collaboratively with a range of stakeholders to design and implement interventions, identifying upstream social determinants of AUDs, developing and evaluating policy interventions such as increased taxation on alcohol, and developing services for special populations (e.g., adolescents) with AUDs.

Neurosteroids (allopregnanolone) and alcohol use disorder: From mechanisms to potential pharmacotherapy

Alcohol Use Disorder (AUD) is a multifaceted relapsing disorder that is commonly comorbid with psychiatric disorders, including anxiety. Alcohol exposure produces a plethora of effects on neurobiology. Currently, therapeutic strategies are limited, and only a few treatments - disulfiram, acamprosate, and naltrexone - are available. Given the complexity of this disorder, there is a great need for the identification of novel targets to develop new pharmacotherapy. The GABAergic system, the primary inhibitory system in the brain, is one of the well-known targets for alcohol and is responsible for the anxiolytic effects of alcohol. Interestingly, GABAergic neurotransmission is fine-tuned by neuroactive steroids that exert a regulatory role on several endocrine systems involved in neuropsychiatric disorders including AUD. Mounting evidence indicates that alcohol alters the biosynthesis of neurosteroids, whereas acute alcohol increases and chronic alcohol decreases allopregnanolone levels. Our recent work highlighted that chronic alcohol-induced changes in neurosteroid levels are mediated by epigenetic modifications, e.g., DNA methylation, affecting key enzymes involved in neurosteroid biosynthesis. These changes were associated with changes in GABAA receptor subunit expression, suggesting an imbalance between excitatory and inhibitory signaling in AUD. This review will recapitulate the role of neurosteroids in the regulation of the neuroendocrine system, highlight their role in the observed allostatic load in AUD, and develop a framework from mechanisms to potential pharmacotherapy.

Perspectives on the pharmacological management of alcohol use disorder: Are the approved medications effective?

INTRODUCTION

In the last decades, many medications have been tested for the treatment of Alcohol Use Disorder (AUD). Among them, disulfiram, acamprosate, naltrexone, nalmefene, sodium oxybate and baclofen have been approved in different countries, with different specific indications. Topiramate is not approved for the treatment of AUD, however, it is suggested as a therapeutic option by the American Psychiatric Association for patients who do not tolerate or respond to approved therapies.

AREAS COVERED

In this narrative review we have analyzed the main studies available in literature, investigating the efficacy and safety of these medications, distinguishing whether they were oriented towards abstinence or not. Randomized controlled studies, analyzing larger populations for longer periods were the main focus of our analysis.

CONCLUSIONS

The medications currently available for the treatment of AUD are quite effective, yet further progress can still be achieved through the personalized strategies. Also, these medications are still markedly underutilized in clinical practice and many patients do not have access to specialized treatment.

Treating Alcohol Use Disorder in Patients with Alcohol-Associated Liver Disease: Controversies in Pharmacological Therapy

Alcohol use disorder (AUD) is one of the main causes of global death and disability. The liver represents the main target of alcohol damage, and alcohol-associated liver disease (ALD) represents the first cause of liver cirrhosis in Western countries. Alcohol abstinence is the main goal of treatment in AUD patients with ALD, as treatments for ALD are less effective when drinking continues. Moreover, the persistence of alcohol consumption is associated with higher mortality, increased need for liver transplantation, and graft loss. The most effective treatment for AUD is the combination of psychosocial interventions, pharmacological therapy, and medical management. However, the effectiveness of these treatments in patients with ALD is doubtful even because AUD patients with ALD are usually excluded from pharmacological trials due to concerns on liver safety. This narrative review will discuss the treatment options for AUD-ALD patients focusing on controversies in pharmacological therapy.

Patient-level interventions to reduce alcohol-related harms in low- and middle-income countries: A systematic review and meta-summary

BACKGROUND

Disease and disability from alcohol use disproportionately impact people in low- and middle-income countries (LMICs). While varied interventions have been shown to reduce alcohol use in high-income countries, their efficacy in LMICs has not been assessed. This systematic review describes current published literature on patient-level alcohol interventions in LMICs and specifically describes clinical trials evaluating interventions to reduce alcohol use in LMICs.

METHODS AND FINDINGS

In accordance with PRISMA, we performed a systematic review using an electronic search strategy from January 1, 1995 to December 1, 2020. Title, abstract, as well as full-text screening and extraction were performed in duplicate. A meta-summary was performed on randomized controlled trials (RCTs) that evaluated alcohol-related outcomes. We searched the following electronic databases: PubMed, EMBASE, Scopus, Web of Science, Cochrane, WHO Global Health Library, and PsycINFO. Articles that evaluated patient-level interventions targeting alcohol use and alcohol-related harm in LMICs were eligible for inclusion. No studies were excluded based on language. After screening 5,036 articles, 117 articles fit our inclusion criteria, 75 of which were RCTs. Of these RCTs, 93% were performed in 13 middle-income countries, while 7% were from 2 low-income countries. These RCTs evaluated brief interventions (24, defined as any intervention ranging from advice to counseling, lasting less than 1 hour per session up to 4 sessions), psychotherapy or counseling (15, defined as an interaction with a counselor longer than a brief intervention or that included a psychotherapeutic component), health promotion and education (20, defined as an intervention encouraged individuals' agency of taking care of their health), or biologic treatments (19, defined as interventions where the biological function of alcohol use disorder (AUD) as the main nexus of intervention) with 3 mixing categories of intervention types. Due to high heterogeneity of intervention types, outcome measures, and follow-up times, we did not conduct meta-analysis to compare and contrast studies, but created a meta-summary of all 75 RCT studies. The most commonly evaluated intervention with the most consistent positive effect was a brief intervention; similarly, motivational interviewing (MI) techniques were most commonly utilized among the diverse array of interventions evaluated.

CONCLUSIONS

Our review demonstrated numerous patient-level interventions that have the potential to be effective in LMICs, but further research to standardize interventions, populations, and outcome measures is necessary to accurately assess their effectiveness. Brief interventions and MI techniques were the most commonly evaluated and had the most consistent positive effect on alcohol-related outcomes.

TRIAL REGISTRATION

Protocol Registry: PROSPERO CRD42017055549.

Behavioral economic analysis of topiramate pharmacotherapy for alcohol: a placebo-controlled investigation of effects on alcohol reinforcing value and delayed reward discounting

RATIONALE

Pharmacotherapies are an important clinical strategy for treating alcohol use disorder and an understanding of their functional mechanisms can inform optimal use. Behavioral economics provides a translational platform that may advance our understanding of the motivational impacts of pharmacotherapies.

OBJECTIVES

This secondary analysis study examined the effect of topiramate, a promising pharmacotherapy for treating alcohol use disorder, on two behavioral economic domains, the reinforcing value of alcohol (alcohol demand and alcohol-specific monetary expenditures) and delayed reward discounting (preference for smaller immediate rewards over larger delayed rewards).

METHODS

A double-blind randomized placebo-controlled study (n = 99) was conducted with non-treatment seeking heavy drinkers, comparing topiramate (target dose of 200 mg/day titrated for 3 weeks and remained at the target dose for 2 weeks) to matched placebo.

RESULTS

We found that compared to placebo, topiramate reduced the reinforcing value of alcohol, as shown by a reduction in two alcohol demand indices (intensity and Omax), money spent per week on alcohol and an almost a 50% increase in days without expenditures on alcohol from baseline. Directionally consistent patterns were also present for breakpoint and elasticity (ps = .08). No significant effects were found for delayed reward discounting.

CONCLUSIONS

This study provides evidence that topiramate reduces alcohol's reinforcing value as measured by alcohol demand and alcohol expenditure. More broadly, these findings support the utility of behavioral economics for understanding how medications reduce alcohol use.

Treating alcohol dependence with an abuse and misuse deterrent formulation of sodium oxybate: Results of a randomised, double-blind, placebo-controlled study

Sodium oxybate (SMO) has been approved in Italy and Austria for the maintenance of abstinence in alcohol dependent (AD) patients. Although SMO is well tolerated in AD patients, cases of abuse and misuse have been reported outside the therapeutic setting. Here we report on a phase IIb double-blind, randomized, placebo-controlled trial for the maintenance of abstinence in AD patients with a new abuse and misuse deterrent formulation of SMO. A total of 509 AD patients were randomized to 12 weeks of placebo or one of four SMO doses (0.75, 1.25, 1.75 or 2.25 g t.i.d.) followed by a one-week medication-free period. The primary endpoint was the percentage of days abstinent (PDA) at end of treatment. An unexpectedly high placebo response (mean 73%, median 92%) was observed. This probably compromised the demonstration of efficacy in the PDA, but several secondary endpoints showed statistically significant improvements. A post-hoc subgroup analysis based on baseline severity showed no improvements in the mild group, but statistically significant improvements in the severe group: PDA: mean difference +15%, Cohen's d = 0.42; abstinence: risk difference +18%, risk ratio = 2.22. No safety concerns were reported. Although the primary endpoint was not significant in the overall population, several secondary endpoints were significant in the intent-to-treat population and post-hoc results showed that treatment with SMO was associated with a significant improvement in severe AD patients which is consistent with previous findings. New trials are warranted that take baseline severity into consideration.

Antagonism of GluK1-containing kainate receptors reduces ethanol consumption by modulating ethanol reward and withdrawal

Alcohol use disorder (AUD) is a neuropsychiatric condition affecting millions of people worldwide. Topiramate (TPM) is an antiepileptic drug that has been shown to reduce ethanol drinking in humans. However, TPM is associated with a variety of adverse effects due to its interaction with many receptor systems and intracellular pathways. GluK1-containing kainate receptors (GluK1*KARs) are non-selectively inhibited by TPM, and genetic association studies suggest that this receptor system could be targeted to reduce drinking in AUD patients. We examined the efficacy of LY466195, a selective inhibitor of GluK1*KAR, in reducing ethanol consumption in the intermittent two-bottle choice paradigm in mice. The effect of LY466195 on various ethanol-related phenotypes was investigated by quantification of alcohol intake, physical signs of withdrawal, conditioned place preference (CPP) and in vivo microdialysis in the nucleus accumbens. Selective GluK1*KAR inhibition reduced ethanol intake and preference in a dose-dependent manner. LY466195 treatment attenuated the physical manifestations of ethanol withdrawal and influenced the rewarding properties of ethanol. Interestingly, LY466195 injection also normalized changes in dopamine levels in response to acute ethanol in ethanol-dependent mice, but had no effect in ethanol-naïve mice, suggesting ethanol state-dependent effects. The data point to GluK1*KARs as an attractive pharmacological target for the treatment of AUD.

Baseline severity and the prediction of placebo response in clinical trials for alcohol dependence: A meta-regression analysis to develop an enrichment strategy

BACKGROUND

There is considerable unexplained variability in alcohol abstinence rates (AR) in the placebo groups of randomized controlled trials (RCTs) for alcohol dependence (AD). This is of particular interest because placebo responses correlate negatively with treatment effect size. Recent evidence suggests that the placebo response is lower in very heavy drinkers who show no "spontaneous improvement" prior to treatment initiation (high-severity population) than in a mild-severity population and in studies with longer treatment duration. We systematically investigated the relationship between population severity, treatment duration, and the placebo response in AR to inform a strategy aimed at reducing the placebo response and thereby increasing assay sensitivity in RCTs for AD.

METHODS

We conducted a systematic literature review on placebo-controlled RCTs for AD.We assigned retained RCTs to high- or mild-severity groups of studies based on baseline drinking risk levels and abstinence duration before treatment initiation. We tested the effects of population severity and treatment duration on the placebo response in AR using meta-regression analysis.

RESULTS

Among the 19 retained RCTs (comprising 1996 placebo-treated patients), 11 trials were high-severity and 8 were mild-severity RCTs. The between-study variability in AR was lower in the high-severity than in the mild-severity studies (interquartile range: 7.4% vs. 20.9%). The AR in placebo groups was dependent on population severity (p = 0.004) and treatment duration (p = 0.017) and was lower in the high-severity studies (16.8% at 3 months) than the mild-severity studies (36.7% at 3 months).

CONCLUSIONS

Pharmacological RCTs for AD should select high-severity patients to decrease the magnitude and variability in the placebo effect and and improve the efficiency of drug development efforts for AD.

Voltage gated sodium channel inhibitors as anticonvulsant drugs: A systematic review on recent developments and structure activity relationship studies

Voltage-gated sodium channel blockers are one of the vital targets for the management of several central nervous system diseases, including epilepsy, chronic pain, psychiatric disorders, and spasticity. The voltage-gated sodium channels play a key role in controlling cellular excitability. This reduction in excitotoxicity is also applied to improve the symptoms of epileptic conditions. The effectiveness of antiepileptic drugs as sodium channel depends upon the reversible blocking of the spontaneous discharge without blocking its propagation. There are number of antiepileptic drug(s) which are in pipeline to flour the market to conquer abnormal neuronal excitability. They inhibit the seizures through the inhibition of complex voltage- and frequency-dependent ionic currents through sodium channels. Over the past decade, the sodium channel is one of the most explored targets to control or treat the seizure, but there has not been any game-changing discovery yet. Although there are large numbers of drugs approved for the treatment of epilepsy, however they are associated with several acute to chronic side effects. Many research groups have tirelessly worked for better therapeutic medication on this popular target to treat epileptic seizures. The review quotes briefly the developments of the approved examples of sodium channel blockers as anticonvulsant drugs. Medicinal chemists have tried the design and development of some more potent anticonvulsant drugs to minimize the toxicity that are discussed here, and an emphasis is given for their possible mechanism and the structure-activity relationship (SAR).

Systematische Literaturübersicht der Wirksamkeit von Acamprosat, Naltrexon, Disulfiram und Nalmefen zur Trinkmengenreduktion und Aufrechterhaltung der Abstinenz bei Alkoholabhängigkeit

Das Ziel der vorliegenden Übersichtsarbeit ist die systematische Darstellung der aktuellen Evidenz zur Wirksamkeit von Acamprosat, Naltrexon, Disulfiram und Nalmefen für die Aufrechterhaltung der Abstinenz oder Trinkmengenreduktion bei alkoholabhängigen Patient:innen. Bezogen auf den Zeitraum 2005 bis 2020 wurden insgesamt 27 Studien identifiziert, die alle Einschlusskriterien (u. a. RCT, mind. 8 Wochen Behandlungsdauer) erfüllten. Es wurden überwiegend Hinweise zur Wirksamkeit von Nalmefen gefunden. Acamprosat war nicht (zusätzlich) wirksam. Naltrexon trug in kombinierten Interventionen einen zusätzlichen Nutzen bei, dies galt jedoch nicht für die Mehrzahl der Studien. Disulfiram war nicht wirksam darin, einen zusätzlichen Nutzen zur Erhaltung der Abstinenz beizutragen, im Vergleich zu Topiramat, einem Antikonvulsivum, jedoch effektiver. Die Ergebnisse stehen nicht im Einklang mit dem bisher bekannten Forschungsstand, der Acamprosat, Naltrexon und Nalmefen als überwiegend effektiv und sicher einstuft und Disulfiram als mäßig wirksam. Der pharmakologische Interventionsbedarf sollte bei Bestehen alkoholbezogener Probleme exploriert und ggf. erwogen werden, damit diesbezüglich Vorbehalte abgebaut und ein umfassendes und zugleich individuelles Behandlungsangebot geschaffen wird. Hinsichtlich der Trinkmengenreduktion sollten Aspekte der Schadensminderung als Behandlungsziel berücksichtigt werden.

World Health Organization risk drinking levels as a treatment outcome measure in topiramate trials

BACKGROUND

Although abstinence has traditionally been considered the only suitable outcome for alcohol treatment, reduced drinking is also associated with improved functioning and medical and psychiatric outcomes. The World Health Organization (WHO) risk drinking levels (RDLs) have been shown to be valid outcome measures in treatment trials for alcohol use disorder (AUD).

METHODS

We conducted a secondary analysis of two 12-week, randomized controlled trials (RCTs), in which a total of 308 individuals with problematic alcohol use received topiramate or placebo treatment. We compared the utility of the WHO RDLs with other treatment outcomes, including self-reported measures of alcohol consumption, alcohol-related problems, and quality of life, and the biomarker gamma-glutamyltransferase.

RESULTS

Topiramate treatment was associated with small effect sizes for both a 1-level (d = 0.26) and a 2-level (d = 0.19) reduction in WHO RDL, effects that were not significant after correction for multiple comparisons. No heavy drinking days, one of the outcome measures recommended by the US Food and Drug Administration for alcohol medication registration trials, also exhibited a small effect (0.21), while an effect size for abstinence could not be calculated. There were medium effects of topiramate on continuous measures of percent heavy drinking days (d = 0.49) and alcohol-related problems (d = 0.41).

CONCLUSIONS

Topiramate is an efficacious pharmacotherapy for AUD. Although continuous measures of drinking and alcohol-related problems yielded larger effect sizes than the WHO RDLs, the latter nonetheless provide a categorical alternative for use in both clinical care and pharmacotherapy trials.

Effects of topiramate on neural responses to alcohol cues in treatment-seeking individuals with alcohol use disorder: preliminary findings from a randomized, placebo-controlled trial

Topiramate, a GABA/glutamate modulator, is efficacious in reducing alcohol consumption, though the mechanisms underlying this effect are not well characterized. This study analyzed functional magnetic resonance imaging (fMRI) data from 22 heavy drinkers enrolled in a 12-week placebo-controlled, randomized clinical trial of topiramate to examine the effects of topiramate on alcohol cue-elicited brain responses, craving, and heavy drinking in individuals with DSM-5 alcohol use disorder. Patients were randomized to receive either topiramate (maximal daily dosage of 200 mg/day) or placebo and were administered an fMRI alcohol cue-reactivity task at baseline (before starting medication) and after 6 weeks of double-blind treatment. Analyses compared the topiramate (n = 12) and placebo (n = 8) groups on (1) the change in brain responses during alcohol cue exposure (vs non-alcohol cues) within five a priori regions of interest related to reward-the bilateral and medial orbitofrontal cortex (OFC) and bilateral ventral striatum (VS) and (2) change in craving and heavy drinking days (HDDs) from baseline and scan 2. Topiramate, relative to placebo, reduced alcohol cue-elicited activation of the left VS, bilateral OFC, and medial OFC, alcohol cue-elicited craving, and HDDs between baseline and 6 weeks of treatment. The reduction in alcohol cue-elicited activation in the medial OFC correlated with reductions in craving, and reduced activation in the right VS, right OFC, and medial OFC correlated with the reduction in HDD. This preliminary study provides evidence that topiramate's attenuation of alcohol cue-elicited brain activation and craving are key elements of the drug's neurobiological mechanism of action in reducing heavy drinking.

Use of Topiramate in the Spectrum of Addictive and Eating Disorders: A Systematic Review Comparing Treatment Schemes, Efficacy, and Safety Features

BACKGROUND AND OBJECTIVE

Topiramate has been approved by the US Food and Drug Administration for the treatment of epilepsy since the 1990s, and it has also been used off-label in the treatment of many types of addictive disorders. To date, no systematic review has embraced the entire field of addiction, both substance use and behavioral addictions, including eating disorders, to compare topiramate-based protocols and the related level of evidence in each addictive disorder. Our objective is to fill this gap.

METHODS

A systematic search was conducted using the MEDLINE, PsycINFO, and Cochrane databases without a date or language limit. All trials and meta-analyses assessing the efficacy of topiramate in alcohol use disorder; cocaine use disorder; methamphetamine, nicotine, cannabis, opiate, and benzodiazepine use disorders; binge eating disorder; bulimia; and pathological gambling were analyzed. The quality of the studies was rated using the Cochrane Risk-of-Bias tool for randomized trials (ROB-2), the Risk of Bias In Nonrandomized Studies (ROBINS-I), or the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist, depending on the study design. Safety features were assessed based on a wider non-systematic review.

RESULTS

Sixty-two articles were reviewed. Treatment protocols were relatively homogenous across addictive disorders, with slow dose titration schemes and a maximum dose range of 200-400 mg per day. The most supportive evidence for topiramate efficacy was found in alcohol use disorder for drinking reduction parameters only. To a lesser extent, topiramate could be a promising therapeutic option for binge eating disorder and cocaine use disorder. Evidence was weak for other addictive disorders. No major tolerability issues were found, provided that basic safety rules were followed. Adverse drug reactions could lead to early treatment discontinuation.

DISCUSSION

Though off-label, addiction specialists should consider topiramate as a second-line option for drinking reduction in alcohol use disorder, as well as for binge eating disorder or cocaine use disorder.

Molecular Correlates of Topiramate and GRIK1 rs2832407 Genotype in Pluripotent Stem Cell-Derived Neural Cultures

BACKGROUND

There is growing evidence that the anticonvulsant topiramate is efficacious in reducing alcohol consumption. Further, an intronic single nucleotide polymorphism (rs2832407, C A) in the GRIK1 gene, which encodes the GluK1 subunit of the excitatory kainate receptor, predicted topiramate's effectiveness in reducing heavy drinking in a clinical trial. The molecular correlates of GRIK1 genotype that may relate to topiramate's ability to reduce drinking remain unknown.

METHODS

We differentiated induced pluripotent stem cells (iPSCs) characterized by GRIK1 rs2832407 genotype from 8 A/A and 8 C/C donors into forebrain-lineage neural cultures. Our differentiation protocol yielded mixed neural cultures enriched for glutamatergic neurons. Basal mRNA expression of the GRIK1 locus was examined via quantitative polymerase chain reaction (qPCR). The effects of acute topiramate exposure on excitatory spontaneous synaptic activity were examined via whole-cell patch-clamp electrophysiology. Results were compared and contrasted between iPSC donor genotypes.

RESULTS

Although characterization of the GRIK1 locus revealed no effect of rs2832407 genotype on GRIK1 isoform mRNA expression, a significant difference was observed on GRIK1 antisense-2 expression, which was greater in C/C neural cultures. Differential effects of acute exposure to 5 μM topiramate were observed on spontaneous synaptic activity in A/A versus C/C neurons, with a smaller reduction in excitatory event frequency observed in C/C donor neurons.

CONCLUSIONS

This work highlights the use of iPSC technologies to study pharmacogenetic treatment effects in psychiatric disorders and furthers our understanding of the molecular effects of topiramate exposure in human neural cells.

Efficacy of pharmacotherapeutics for patients comorbid with alcohol use disorders and depressive symptoms-A bayesian network meta-analysis

Background

We aimed to compare and rank the efficacy of different pharmacotherapeutics for patients comorbid with alcohol use disorders and depressive symptoms.

Method

Bayesian network meta‐analysis was performed for three different outcome parameters: alcohol use disorders (AUD) remission rate, percent abstinent days, and scores of depression scales. The surface under the cumulative ranking curves (SUCRA) was used for ranking the efficacy of interventions. Sensitivity analysis and direct pairwise analysis were conducted to validate the main results.

Results

A total of 68 RCTs consisting of 5890 patients were included. Disulfiram could significantly increase the AUD remission rates (OR 5.02, 1.97‐12.95) and the percent abstinent days (MD 17.08, 3.48‐30.93). Disulfiram was associated with the best efficacy in achieving remission (SUCRA 95.1%) and increasing abstinent days (SUCRA 87.6%). Noradrenaline reuptake inhibitor was significantly more efficacious than controls (SMD −2.44, −3.53 to −1.36) and have the first rank (SUCRA 99.0%) in reducing the scores of depression scales. Antiepileptics have relatively higher ranks in efficacy for both AUD and depressive symptoms.

Conclusions

Disulfiram was associated with the best efficacy in achieving abstinence for comorbidity patients. Noradrenaline reuptake inhibitor was demonstrated to be associated with the best efficacy in reducing scores of depression scales. Antiepileptics might be beneficial to both alcohol‐related and depressive symptoms.

Topiramate Pharmacotherapy for Alcohol Use Disorder and Other Addictions: A Narrative Review

: Topiramate is a non-benzodiazepine anticonvulsant medication with multi-faceted pharmacologic action. It has emerged as an efficacious pharmacotherapeutic option for the treatment of addiction, especially alcohol use disorder (AUD). We present a broad narrative review of the putative mechanism of action and clinical utility of topiramate with regard to AUD and other substance use disorders. Collective evidence suggests topiramate is an effective treatment option in AUD, with notable efficacy in reducing harmful drinking patterns in AUD. Though not currently approved by the United States Food and Drug Administration for the indication of AUD, topiramate should be considered as a pharmacological treatment option with high utility among AUD patients. Early pharmacogenetic studies raise the intriguing possibility of identifying patients likely to respond to topiramate using genetic testing, and initial studies show that topiramate may also be useful in treating cocaine use disorder, smoking cessation and behavioral addictions. However, further research is needed in all these areas.

Smoking characteristics and alcohol use among women in treatment for alcohol use disorder

BACKGROUND

Understanding the association between smoking and alcohol use among women may help inform the delivery of targeted interventions to address both of these health behaviors.

METHODS

This study analyzed data from N = 138 women enrolled in a randomized clinical trial comparing female-specific individual versus group cognitive-behavior therapy for alcohol use disorder (AUD). We assessed cigarette use patterns, participants' interest in quitting smoking and motivation to quit smoking during treatment for AUD, and examined the relationship between smoking and alcohol use before and during alcohol treatment.

RESULTS

Over a third of the sample reported smoking cigarettes at baseline (N = 47, 34.1%), with the majority of smokers reporting daily cigarette use. At baseline, those who smoked reported a high interest in quitting smoking M = 7.8 out of 10 (SD = 2.7), although most believed they should quit smoking only after achieving some success in quitting drinking (50.0%). However, participants who smoked cigarettes (compared to non-smokers) reported more alcohol abuse and dependence symptoms (p = .001), lower rates of completing the alcohol treatment (p = .03), attended significantly fewer treatment sessions (p = .008), and consumed significantly more drinks per day on average both at baseline (p = .002) and during the treatment period (p = .04).

CONCLUSIONS

Findings suggest that women with AUD who also smoke cigarettes have greater difficulty engaging in or responding to treatment for their alcohol use. However, these participants reported high interest in quitting smoking but low perceived readiness during AUD treatment, suggesting that motivational interventions should be considered that could take advantage of the opportunity to treat women for both of these co-occurring behaviors while in treatment.

Sleep and the Pharmacotherapy of Alcohol Use Disorder: Unfortunate Bedfellows. A Systematic Review With Meta-Analysis

Background: Sleep disorders are commonly associated with acute and chronic use of alcohol and with abstinence. To date, there are four approved drugs to treat alcohol use disorder (AUD): disulfiram, acamprosate, naltrexone, and nalmefene. These AUD therapies reduce the craving and risk of relapse into heavy drinking, but little is known about their effect on sleep. As recent evidences indicate a crucial role of sleep disorders in AUD, claiming that sleep problems may trigger alcohol abuse and relapses, it is fundamental to clarify the impact of those drugs on the sleep quality of AUD patients. This systematic review aims to answer the question: how does the pharmacotherapy for AUD affect sleep? Methods: We searched PubMed, Embase, CINAHL Plus, Cochrane, and Scopus using sleep- and AUD pharmacotherapy-related keywords. The articles included were appraised using the CASP checklists, and the risk of bias was assessed following the Cochrane risk-of-bias assessment tool. Finally, we pooled sleep outcomes in a meta-analysis to measure the overall effect. Results and Conclusion: We included 26 studies: only three studies focused on sleep as a main outcome, two with polysomnography (objective measurement), and one with subjective self-reported sleep, while all the other studies reported sleep problems among the adverse effects (subjective report). The only study available on disulfiram showed reduced REM sleep. Acamprosate showed no/little effect on self-reported sleep but improved sleep continuity and architecture measured by polysomnography. The two opioidergic drugs naltrexone and nalmefene had mainly detrimental effect on sleep, giving increased insomnia and/or somnolence compared with placebo, although not always significant. The meta-analysis confirmed significantly increased somnolence and insomnia in the naltrexone group, compared with the placebo. Overall, the currently available evidences show more sleep problems with the opioidergic drugs (especially naltrexone), while acamprosate seems to be well tolerated or even beneficial. Acamprosate might be a more suitable choice when patients with AUD report sleep problems. Due to the paucity of information available, and with the majority of results being subjective, more research on this topic is needed to further inform the clinical practice, ideally with more objective measurements such as polysomnography.

Vibration of effects from diverse inclusion/exclusion criteria and analytical choices: 9216 different ways to perform an indirect comparison meta-analysis

BACKGROUND

Different methodological choices such as inclusion/exclusion criteria and analytical models can yield different results and inferences when meta-analyses are performed. We explored the range of such differences, using several methodological choices for indirect comparison meta-analyses to compare nalmefene and naltrexone in the reduction of alcohol consumption as a case study.

METHODS

All double-blind randomized controlled trials (RCTs) comparing nalmefene to naltrexone or one of these compounds to a placebo in the treatment of alcohol dependence or alcohol use disorders were considered. Two reviewers searched for published and unpublished studies in MEDLINE (August 2017), the Cochrane Library, Embase, and ClinicalTrials.gov and contacted pharmaceutical companies, the European Medicines Agency, and the Food and Drug Administration. The indirect comparison meta-analyses were performed according to different inclusion/exclusion criteria (based on medical condition, abstinence of patients before inclusion, gender, somatic and psychiatric comorbidity, psychological support, treatment administered and dose, treatment duration, outcome reported, publication status, and risk of bias) and different analytical models (fixed and random effects). The primary outcome was the vibration of effects (VoE), i.e. the range of different results of the indirect comparison between nalmefene and naltrexone. The presence of a "Janus effect" was investigated, i.e. whether the 1st and 99th percentiles in the distribution of effect sizes were in opposite directions.

RESULTS

Nine nalmefene and 51 naltrexone RCTs were included. No study provided a direct comparison between the drugs. We performed 9216 meta-analyses for the indirect comparison with a median of 16 RCTs (interquartile range = 12-21) included in each meta-analysis. The standardized effect size was negative at the 1st percentile (- 0.29, favouring nalmefene) and positive at the 99th percentile (0.29, favouring naltrexone). A total of 7.1% (425/5961) of the meta-analyses with a negative effect size and 18.9% (616/3255) of those with a positive effect size were statistically significant (p < 0.05).

CONCLUSIONS

The choice of inclusion/exclusion criteria and analytical models for meta-analysis can result in entirely opposite results. VoE evaluations could be performed when overlapping meta-analyses on the same topic yield contradictory result.

TRIAL REGISTRATION

This study was registered on October 19, 2016, in the Open Science Framework (OSF, protocol available at https://osf.io/7bq4y/ ).

Topiramate in the treatment of cocaine use disorder

PURPOSE

The literature on topiramate use in cocaine-dependent patients was reviewed.

SUMMARY

Six randomized, double-blind, controlled clinical trials evaluating the use of topiramate in patients who were cocaine dependent were analyzed. The results from the studies indicated that topiramate, when used in combination with cognitive behavioral therapy, may be effective in reducing short-term cocaine use and should be considered as a possible treatment option. Other trials suggested that topiramate was not effective in patients with a dual diagnosis of opioid and cocaine dependence. Two trials suggested that short-term abstinence assisted by pharmacotherapy is a predictor of longer-term (6 months and 1 year, respectively) abstinence. Cocaine use is dependent on multiple factors; therefore, a reduction in use or craving is not definitively associated with abstinence. However, decreased use reduces potential patient harm and the amount of money spent on illicit cocaine. The findings of this literature review should be used to encourage the completion of more trials that are appropriately designed. Topiramate was shown to be effective for increasing cocaine abstinence, the proportion of cocaine nonuse days, and the proportion of patients to attain 3 consecutive weeks of cocaine abstinence and decreasing the abuse liability of cocaine. Conflicting results in clinical trials do not provide a definitive answer regarding topiramate's efficacy in managing cocaine dependence.

CONCLUSION

Available research neither validates nor invalidates the hypothesis that topiramate is efficacious in attaining abstinence in cocaine-dependent patients.

Topiramate versus naltrexone for alcohol use disorder: study protocol for a genotype-stratified, double-blind randomised controlled trial (TOP study)

Background

Current treatments for alcohol use disorders have limited efficacy and there is a high degree of variability in treatment response. In a randomised, placebo-controlled clinical trial, there was a large effect size for topiramate in people homozygous for the GRIK1 rs2832407*C allele. The primary aim of the TOP study is to examine prospectively the therapeutic and cost-effectiveness of topiramate versus an active control (naltrexone) in improving treatment outcomes for alcohol dependence. Participants will be stratified on rs2832407 to compare C-allele homozygotes with A-allele carriers to examine the moderating effect of rs2832407 on drinking outcomes. An exploratory aim is to examine the moderating effects of rs1799971, a polymorphism in OPRM1, on the response to naltrexone by comparing Asn40 homozygotes with Asp40 carriers.

Methods/design

This double-blind trial will randomise 180 alcohol-dependent participants to a 12-week regime of either topiramate (titrating the dose up to 200 mg/day) or naltrexone (50 mg/day). Participants will be stratified on the two polymorphisms before randomisation. All participants will receive medical management. The primary drinking outcome will be the number of heavy drinking days per week and secondary drinking outcomes will include the time to relapse, the time to lapse and the percentage of abstinent days. Other secondary outcomes will include body mass index, tobacco use, anxiety symptoms and depressive symptoms.

Discussion

If successful, the TOP study will improve management strategies for alcohol dependence by providing support for the use of genetic biomarkers to inform medication selection.

Trial registration

ClinicalTrials.gov, NCT03479086. Registered on 27 March 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2824-z) contains supplementary material, which is available to authorized users.

Adding Psychotherapy to the Naltrexone Treatment of Alcohol Use Disorder: Meta-analytic Review

Background

It remains unclear if naltrexone combined with psychotherapy is superior to naltrexone alone in treating alcohol use disorders (AUD). The current meta-analysis examined the hypothesis that psychotherapy is a significant moderator that influences AUD-related outcomes and that naltrexone combined with psychotherapy is associated with significantly better AUD-related outcomes than naltrexone alone.

Methods

A total of 30 studies (N_naltrexone = 2317; N_placebo = 2056) were included. Random effects model meta-analyses were carried out for each of the studied outcomes. Subsequently, the random effects model pooled estimates from studies with and without psychotherapy were compared using a Wald test. A mixed-effect model, incorporating psychotherapy as a moderator, was used to examine the impact of psychotherapy on treatment outcomes.

Results

Naltrexone had a significant treatment effect on abstinence relapse and Gamma-Glutamyl Transferase levels, but not cravings. The pooled estimates for studies with and without psychotherapy were not significantly different for any of the studied outcomes. Psychotherapy was not a significant moderator in the mixed effects models for any of the studied outcomes.

Conclusions

Naltrexone treatment is efficacious in reducing alcohol consumption, but not reducing cravings. Adding psychotherapy on top naltrexone did not result in any significant additional benefit for AUD patients.

Medications for alcohol use disorders: An overview

Patients who suffer from alcohol use disorders (AUDs) usually go through various socio-behavioral and pathophysiological changes that take place in the brain and other organs. Recently, consumption of unhealthy food and excess alcohol along with a sedentary lifestyle has become a norm in both developed and developing countries. Despite the beneficial effects of moderate alcohol consumption, chronic and/or excessive alcohol intake is reported to negatively affect the brain, liver and other organs, resulting in cell death, organ damage/failure and death. The most effective therapy for alcoholism and alcohol related comorbidities is alcohol abstinence, however, chronic alcoholic patients cannot stop drinking alcohol. Therefore, targeted therapies are urgently needed to treat such populations. Patients who suffer from alcoholism and/or alcohol abuse experience harmful effects and changes that occur in the brain and other organs. Upon stopping alcohol consumption, alcoholic patients experience acute withdrawal symptoms followed by a protracted abstinence syndrome resulting in the risk of relapse to heavy drinking. For the past few decades, several drugs have been available for the treatment of AUDs. These drugs include medications to reduce or stop severe alcohol withdrawal symptoms during alcohol detoxification as well as recovery medications to reduce alcohol craving and support abstinence. However, there is no drug that completely antagonizes the adverse effects of excessive amounts of alcohol. This review summarizes the drugs which are available and approved by the FDA and their mechanisms of action as well as the medications that are under various phases of preclinical and clinical trials. In addition, the repurposing of the FDA approved drugs, such as anticonvulsants, antipsychotics, antidepressants and other medications, to prevent alcoholism and treat AUDs and their potential target mechanisms are summarized.

Advancing Pharmacotherapy Development from Preclinical Animal Studies

Animal models provide rapid, inexpensive assessments of an investigational drug's therapeutic potential. Ideally, they support the plausibility of therapeutic efficacy and provide a rationale for further investigation. Here, I discuss how the absence of clear effective-ineffective categories for alcohol use disorder (AUD) medications and biases in the clinical and preclinical literature affect the development of predictive preclinical alcohol dependence (AD) models. Invoking the analogical argument concept from the philosophy of science field, I discuss how models of excessive alcohol drinking support the plausibility of clinical pharmacotherapy effects. Even though these models are not likely be completely discriminative, they are sensitive to clinically effective medications and have revealed dozens of novel medication targets. In that context, I discuss recent preclinical work on GLP-1 receptor agonists, phosphodiesterase inhibitors, glucocorticoid receptor antagonists, nociception agonists and antagonists, and CRF1 antagonists. Clinically approved medications are available for each of these drug classes. I conclude by advocating a translational approach in which drugs are evaluated highly congruent preclinical models and human laboratory studies. Once translation is established, I suggest the burden is to develop hypothesis-based therapeutic interventions maximizing the impact of the confirmed pharmacotherapeutic effects in the context of additional variables falling outside the model.

The Corticotropin Releasing Factor Receptor 1 in Alcohol Use Disorder: Still a Valid Drug Target?

Corticotropin releasing factor (CRF) is a neuropeptide that plays a key role in behavioral and physiological responses to stress. A large body of animal literature implicates CRF acting at type 1 CRF receptors (CRFR1) in consumption by alcohol-dependent subjects, stress-induced reinstatement of alcohol seeking, and possibly binge alcohol consumption. These studies have encouraged recent pilot studies of CRFR1 antagonists in humans with alcohol use disorder (AUD). It was a great disappointment to many in the field that these studies failed to show an effect of these compounds on stress-induced alcohol craving. Here, we examine these studies to explore potential limitations and discuss preclinical and human literature to ask whether CRFR1 is still a valid drug target to pursue for the treatment of AUD.

A Novel Therapy for cocaine dependence during abstinence: A randomized clinical trial

Background

Topiramate is an anticonvulsant drug and an ideal candidate for reducing the craving in people relying on cocaine. Contingency management is one of the common therapies in the domain of addiction.

Objective

The present study aimed to evaluate and compare three medication methods of Topiramate (TPM), Contingency Management (CM) and the combined TPM treatment and cash intervention on craving during abstinence.

Methods

This randomized clinical trial was conducted at Bijan Center for Substance Abuse Treatment in Tehran, Iran, from December 15, 2014 to November 20, 2015. One hundred males (Age range=18–34; SD=4.11) undergoing abstinence were assigned randomly to four groups (n=25) of Topiramate (TPM), Contingency Management (CM) and the Combined Method plus a placebo control group. Treatment was provided for twelve weeks for the experiment groups, and only the control group received the placebo. Participants in the Cash-based and CM Condition had an identical 12-week escalating schedule of reinforcement (cash-based incentives worth $0, $20, $40, and $80). Also, in the Topiramate group, participants’ dosage ranged between 25–300 mg/day in escalating doses) 25, 50, 100, 150, 200, 250, 300). In addition, all subjects received brief behavioral compliance enhancement treatment (BBCET). Participants took a urine test twice a week, with a given threshold of > 300 ng/ml, and indicators of cocaine craving (response rate= 91%) was evaluated in two phases of pre-test and post-test. We used Chi square, ANCOVA Univariate Model and Scheffe’s post hoc to analyze the primary and secondary outcomes. Also, the qualitative data resulted from demographic evaluations were coded and analyzed by the instrument of analysis of qualitative data i.e. Atlas.ti, Version 5.2.

Results

The results showed that all three types of treatment played a significant efficacy in reducing the craving. The mean (95% CI) scores of craving was 12.04 (p=0.05) with TPM, 13.89 (p=0.05) with CM, 10.92 (p=0.01) with Mix and 16.89 (p>0.05) with control. Moreover, the highest variance explaining the changes in craving was assigned to the combined treatment (p<0.01).

Conclusions

The findings of this study, while having applicable aspects in this domain, can be helpful in planning supplementary remedial procedures.

Trial registration

The trial was registered at the Thai Clinical Trial Registration Center with the TCR ID: TCTR20170112001.

Funding

The authors received no financial support for the research, authorship, and/or publication of this article.

The Nucleus Accumbens: Mechanisms of Addiction across Drug Classes Reflect the Importance of Glutamate Homeostasis

The nucleus accumbens is a major input structure of the basal ganglia and integrates information from cortical and limbic structures to mediate goal-directed behaviors. Chronic exposure to several classes of drugs of abuse disrupts plasticity in this region, allowing drug-associated cues to engender a pathologic motivation for drug seeking. A number of alterations in glutamatergic transmission occur within the nucleus accumbens after withdrawal from chronic drug exposure. These drug-induced neuroadaptations serve as the molecular basis for relapse vulnerability. In this review, we focus on the role that glutamate signal transduction in the nucleus accumbens plays in addiction-related behaviors. First, we explore the nucleus accumbens, including the cell types and neuronal populations present as well as afferent and efferent connections. Next we discuss rodent models of addiction and assess the viability of these models for testing candidate pharmacotherapies for the prevention of relapse. Then we provide a review of the literature describing how synaptic plasticity in the accumbens is altered after exposure to drugs of abuse and withdrawal and also how pharmacological manipulation of glutamate systems in the accumbens can inhibit drug seeking in the laboratory setting. Finally, we examine results from clinical trials in which pharmacotherapies designed to manipulate glutamate systems have been effective in treating relapse in human patients. Further elucidation of how drugs of abuse alter glutamatergic plasticity within the accumbens will be necessary for the development of new therapeutics for the treatment of addiction across all classes of addictive substances.

Metabotropic and ionotropic glutamate receptors as potential targets for the treatment of alcohol use disorder

Emerging evidence indicates that dysfunctional glutamate neurotransmission is critical in the initiation and development of alcohol and drug dependence. Alcohol consumption induced downregulation of glutamate transporter 1 (GLT-1) as reported in previous studies from our laboratory. Glutamate is the major excitatory neurotransmitter in the brain, which acts via interactions with several glutamate receptors. Alcohol consumption interferes with the glutamatergic signal transmission by altering the functions of these receptors. Among the glutamate receptors involved in alcohol-drinking behavior are the metabotropic receptors such as mGluR1/5, mGluR2/3, and mGluR7, as well as the ionotropic receptors, NMDA and AMPA. Preclinical studies using agonists and antagonists implicate these glutamatergic receptors in the development of alcohol use disorder (AUD). Therefore, the purpose of this review is to discuss the neurocircuitry involving glutamate transmission in animals exposed to alcohol and further outline the role of metabotropic and ionotropic receptors in the regulation of alcohol-drinking behavior. This review provides ample information about the potential therapeutic role of glutamatergic receptors for the treatment of AUD.

Interventions for tobacco use cessation in people in treatment for or recovery from substance use disorders

BACKGROUND

Smoking rates in people with alcohol and other drug dependencies are two to four times those of the general population. Concurrent treatment of tobacco dependence has been limited due to concern that these interventions are not successful in this population or that recovery from other addictions could be compromised if tobacco cessation was combined with other drug dependency treatment.

OBJECTIVES

To evaluate whether interventions for tobacco cessation are associated with tobacco abstinence for people in concurrent treatment for or in recovery from alcohol and other drug dependence.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and clinicaltrials.gov databases, with the most recent search completed in August 2016. A grey literature search of conference abstracts from the Society on Nicotine Research and Treatment and the ProQuest database of digital dissertations yielded one additional study, which was excluded.

SELECTION CRITERIA

We included randomised controlled trials assessing tobacco cessation interventions among people in concurrent treatment for alcohol or other drug dependence or in outpatient recovery programmes.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study risk of bias and extracted data. We resolved disagreements by consensus. The primary outcome was abstinence from tobacco use at the longest period of follow-up, and the secondary outcome was abstinence from alcohol or other drugs, or both. We reported the strictest definition of abstinence. We summarised effects as risk ratios and 95% confidence intervals (CI). Two clustered studies did not provide intraclass correlation coefficients, and were excluded from the sensitivity analysis. We used the I² statistic to assess heterogeneity.

MAIN RESULTS

Thirty-five randomised controlled trials, one ongoing, involving 5796 participants met the criteria for inclusion in this review. Included studies assessed the efficacy of tobacco cessation interventions, including counselling, and pharmacotherapy consisting of nicotine replacement therapy (NRT) or non-NRT, or the two combined, in both inpatient and outpatient settings for participants in treatment and in recovery. Most studies did not report information to assess the risk of allocation, selection, and attrition bias, and were classified as unclear.Analyses considered the nature of the intervention, whether participants were in treatment or recovery and the type of dependency. Of the 34 studies included in the meta-analysis, 11 assessed counselling, 11 assessed pharmacotherapy, and 12 assessed counselling in combination with pharmacotherapy, compared to usual care or no intervention. Tobacco cessation interventions were significantly associated with tobacco abstinence for two types of interventions. Pharmacotherapy appeared to increase tobacco abstinence (RR 1.60, 95% CI 1.22 to 2.12, 11 studies, 1808 participants, low quality evidence), as did combined counselling and pharmacotherapy (RR 1.74, 95% CI 1.39 to 2.18, 12 studies, 2229 participants, low quality evidence) at the period of longest follow-up, which ranged from six weeks to 18 months. There was moderate evidence of heterogeneity (I² = 56% with pharmacotherapy and 43% with counselling plus pharmacotherapy). Counselling interventions did not significantly increase tobacco abstinence (RR 1.33, 95% CI 0.90 to 1.95).Interventions were significantly associated with tobacco abstinence for both people in treatment (RR 1.99, 95% CI 1.59 to 2.50) and people in recovery (RR 1.33, 95% CI 1.06 to 1.67), and for people with alcohol dependence (RR 1.47, 95% CI 1.20 to 1.81) and people with other drug dependencies (RR 1.85, 95% CI 1.43 to 2.40).Offering tobacco cessation therapy to people in treatment or recovery for other drug dependence was not associated with a difference in abstinence rates from alcohol and other drugs (RR 0.97, 95% CI 0.91 to 1.03, 11 studies, 2231 participants, moderate evidence of heterogeneity (I² = 66%)).Data on adverse effect of the interventions were limited.

AUTHORS' CONCLUSIONS

The studies included in this review suggest that providing tobacco cessation interventions targeted to smokers in treatment and recovery for alcohol and other drug dependencies increases tobacco abstinence. There was no evidence that providing interventions for tobacco cessation affected abstinence from alcohol and other drugs. The association between tobacco cessation interventions and tobacco abstinence was consistent for both pharmacotherapy and combined counselling and pharmacotherapy, for participants both in treatment and in recovery, and for people with alcohol dependency or other drug dependency. The evidence for the interventions was low quality due primarily to incomplete reporting of the risks of bias and clinical heterogeneity in the nature of treatment. Certain results were sensitive to the length of follow-up or the type of pharmacotherapy, suggesting that further research is warranted regarding whether tobacco cessation interventions are associated with tobacco abstinence for people in recovery, and the outcomes associated with NRT versus non-NRT or combined pharmacotherapy. Overall, the results suggest that tobacco cessation interventions incorporating pharmacotherapy should be incorporated into clinical practice to reduce tobacco addiction among people in treatment for or recovery from alcohol and other drug dependence.

Are Alcohol Anti-relapsing and Alcohol Withdrawal Drugs Useful in Cannabinoid Users?

Cannabinoids are still classified as illegal psychoactive drugs despite their broad and increasingly acknowledged therapeutic potential. These substances are most famous for their wide recreational use, particularly among young adults to either alter the state of consciousness, intensify pleasure induced by other psychoactive substances or as an alternative to the previously abused drugs. It is important to emphasize that cannabinoids are often taken together with a variety of medications intended for the treatment of alcohol use disorder (AUD) or alcohol withdrawal syndrome (AWS). These medications include disulfiram, acamprosate, and naltrexone. In this paper, we summarize recent advances in the knowledge of possible beneficial effects and interactions between cannabinoids and drugs commonly used for treatment of AUD and AWS either comorbid or existing as a separate disorder.

Critical needs in drug discovery for cessation of alcohol and nicotine polysubstance abuse

Polysubstance abuse of alcohol and nicotine has been overlooked in our understanding of the neurobiology of addiction and especially in the development of novel therapeutics for its treatment. Estimates show that as many as 92% of people with alcohol use disorders also smoke tobacco. The health risks associated with both excessive alcohol consumption and tobacco smoking create an urgent biomedical need for the discovery of effective cessation treatments, as opposed to current approaches that attempt to independently treat each abused agent. The lack of treatment approaches for alcohol and nicotine abuse/dependence mirrors a similar lack of research in the neurobiology of polysubstance abuse. This review discusses three critical needs in medications development for alcohol and nicotine co-abuse: (1) the need for a better understanding of the clinical condition (i.e. alcohol and nicotine polysubstance abuse), (2) the need to better understand how these drugs interact in order to identify new targets for therapeutic development and (3) the need for animal models that better mimic this human condition. Current and emerging treatments available for the cessation of each drug and their mechanisms of action are discussed within this context followed by what is known about the pharmacological interactions of alcohol and nicotine. Much has been and will continue to be gained from studying comorbid alcohol and nicotine exposure.

Biobehavioral mechanisms of topiramate's effects on alcohol use: an investigation pairing laboratory and ecological momentary assessments

Topiramate reduces drinking, but little is known about the mechanisms that precipitate this effect. This double-blind randomized placebo-controlled study assessed the putative mechanisms by which topiramate reduces alcohol use among 96 adult non-treatment-seeking heavy drinkers in a laboratory-based alcohol cue reactivity assessment and in the natural environment using ecological momentary assessment methods. Topiramate reduced the quantity of alcohol heavy drinkers consumed on drinking days and reduced craving while participants were drinking but did not affect craving outside of drinking episodes in either the laboratory or in the natural environment. Topiramate did not alter the stimulant or sedative effects of alcohol ingestion during the ascending limb of the blood alcohol curve. A direct test of putative mechanisms of action using multilevel structural equation mediation models showed that topiramate reduced drinking indirectly by blunting alcohol-induced craving. These findings provide the first real-time prospective evidence that topiramate reduces drinking by reducing alcohol's priming effects on craving and highlight the importance of craving as an important treatment target of pharmacotherapy for alcoholism.

Alcohol liver disease: A review of current therapeutic approaches to achieve long-term abstinence

Harmful alcohol drinking may lead to significant damage on any organ or system of the body. Alcoholic liver disease (ALD) is the most prevalent cause of advanced liver disease in Europe. In ALD, only alcohol abstinence was associated with a better long-term survival. Therefore, current effective therapeutic strategy should be oriented towards achieving alcohol abstinence or a significant reduction in alcohol consumption. Screening all primary care patients to detect those cases with alcohol abuse has been proposed as population-wide preventive intervention in primary care. It has been suggested that in patients with mild alcohol use disorder the best approach is brief intervention in the primary care setting with the ultimate goal being abstinence, whereas patients with moderate-to-severe alcohol use disorder must be referred to specialized care where detoxification and medical treatment of alcohol dependence must be undertaken.

The efficacy of acamprosate and naltrexone in the treatment of alcohol dependence, Europe versus the rest of the world: a meta-analysis

AIMS

To determine the efficacy of acamprosate and naltrexone in the treatment of those who are alcohol-dependent in reducing lapse/relapse to alcohol consumption and treatment discontinuation, and to examine whether a proportion of the variance in study outcome can be explained by the country in which the trials have taken place.

METHOD

A systematic review and meta-analysis of randomized controlled trials published before September 2013 was conducted. The primary outcome measures were the efficacy of acamprosate or naltrexone in reducing lapse/relapse compared to placebo in the treatment of alcohol dependence and treatment discontinuation. Twenty-two randomized controlled trials (RCTs) of the efficacy of acamprosate met inclusion criteria for the meta-analysis, with a total of 2649 participants in the acamprosate group and 2587 in the placebo group. Twenty-seven RCTs of the efficacy of naltrexone met inclusion criteria for the meta-analysis, with a total of 2253 participants in the naltrexone group and 1946 in the placebo group. A random-effects model using a Mantel-Haenszel method was applied to conduct the meta-analysis. Variance in study outcomes was explored using subgroup analysis of Europe versus the rest of the world (ROW).

RESULTS

The risk of returning to any drinking at 6 months was significantly lower for acamprosate [risk ratio (RR) = 0.83, 95% confidence interval (CI) = 0.78-0.89]. There was little difference in the risk of participants discontinuing treatment for any reason (RR = 0.91, 95% CI = 0.83-1.00) or due to adverse events (RR = 1.30, 95% CI = 0.96-1.75) for the acamprosate compared to placebo groups. The risk of individuals returning to any drinking at approximately 3 months was reduced significantly for the naltrexone group (RR = 0.92, 95% CI = 0.86-1.00), as was the risk of individuals relapsing to heavy drinking at 3 months (RR = 0.85, 95% CI = 0.78-0.93). There was no significant difference between naltrexone and placebo for the risk of individuals discontinuing treatment for any reason (RR = 0.94, 95% CI = 0.84-1.05). There was a significantly greater risk of participants in the naltrexone group discontinuing treatment due to adverse events compared to placebo (RR = 1.72, 95% CI = 1.10-2.70). Subgroup analysis by country (Europe versus ROW) revealed no difference in risk between acamprosate and placebo for the outcomes returning to any drinking at 6 months and discontinuing treatment due to adverse events. For the outcome discontinuation of treatment for any reason, there was a significant difference in RR between Europe and the ROW (χ(2)  = 11.65, P <0.001) for acamprosate. Acamprosate was associated with a reduction in risk of discontinuing treatment for Europe (RR = 0.86, 95% CI = 0.79-0.95), but an increase in risk of discontinuing treatment for ROW (RR = 1.23, 95% CI = 1.03-1.48).

CONCLUSIONS

Both acamprosate and naltrexone appear to reduce the risk of individuals returning to drinking alcohol in those who are alcohol-dependent. The country in which a randomized control trial (RCT) for the efficacy of acamprosate and naltrexone is completed does not appear to explain the variance in trial outcomes for returning to drinking alcohol or discontinuing drinking due to adverse effects. However, the country in which the RCT of acamprosate are completed may be important for explaining the variance between studies for the outcome 'discontinuing treatment for any reason'.

Topiramate in Alcohol Use Disorders: Review and Update

To date, a limited number of pharmacological agents exist to treat alcohol use disorders (AUDs), and there is growing interest in new therapeutic tools. In this framework, topiramate may represent a useful treatment option, although its use is not yet approved for AUDs. The main focus of this review is to discuss all the existing data supporting the use of topiramate in AUDs, with an emphasis on the most recent and relevant clinical implications. In addition, the profile of the alcoholic patient who may benefit more from the use of topiramate is outlined. In this regard, the authors conducted a PubMed search of clinical human studies published in English using the following key words: topiramate alcohol dependence, topiramate alcohol withdrawal and topiramate alcoholism. The evidence suggests that topiramate could be an effective treatment option for the management of AUDs, while there are limited results for its use to treat alcohol withdrawal syndrome. In particular, topiramate shows a greater beneficial effect in subjects with a typology of craving characterised by drinking obsessions and automaticity of drinking. Topiramate, within the dosage range of 75-300 mg/day, could be considered as a first-line treatment option for the management of AUDs. Its use appears to be safe and well-tolerated, especially in light of very recent findings.

Targeting glutamate uptake to treat alcohol use disorders

Alcoholism is a serious public health concern that is characterized by the development of tolerance to alcohol's effects, increased consumption, loss of control over drinking and the development of physical dependence. This cycle is often times punctuated by periods of abstinence, craving and relapse. The development of tolerance and the expression of withdrawal effects, which manifest as dependence, have been to a great extent attributed to neuroadaptations within the mesocorticolimbic and extended amygdala systems. Alcohol affects various neurotransmitter systems in the brain including the adrenergic, cholinergic, dopaminergic, GABAergic, glutamatergic, peptidergic, and serotonergic systems. Due to the myriad of neurotransmitter and neuromodulator systems affected by alcohol, the efficacies of current pharmacotherapies targeting alcohol dependence are limited. Importantly, research findings of changes in glutamatergic neurotransmission induced by alcohol self- or experimenter-administration have resulted in a focus on therapies targeting glutamatergic receptors and normalization of glutamatergic neurotransmission. Glutamatergic receptors implicated in the effects of ethanol include the ionotropic glutamate receptors (AMPA, Kainate, and NMDA) and some metabotropic glutamate receptors. Regarding glutamatergic homeostasis, ceftriaxone, MS-153, and GPI-1046, which upregulate glutamate transporter 1 (GLT1) expression in mesocorticolimbic brain regions, reduce alcohol intake in genetic animal models of alcoholism. Given the hyperglutamatergic/hyperexcitable state of the central nervous system induced by chronic alcohol abuse and withdrawal, the evidence thus far indicates that a restoration of glutamatergic concentrations and activity within the mesocorticolimbic system and extended amygdala as well as multiple memory systems holds great promise for the treatment of alcohol dependence.

Anticonvulsants for the treatment of alcohol withdrawal syndrome and alcohol use disorders

Alcoholic patients suffer from harmful allostatic neuroplastic changes in the brain causing an acute withdrawal syndrome upon cessation of drinking followed by a protracted abstinence syndrome and an increased risk of relapse to heavy drinking. Benzodiazepines have long been the treatment of choice for detoxifying patients and managing alcohol withdrawal syndrome (AWS). Non-benzodiazepine anticonvulsants (NBACs) are increasingly being used both for alcohol withdrawal management and for ongoing outpatient treatment of alcohol dependence, with the goal of either abstinence or harm reduction. This expert narrative review summarizes the scientific basis and clinical evidence supporting the use of NBACs in treating AWS and for reducing harmful drinking patterns. There is less evidence in support of NBAC therapy for AWS, with few placebo-controlled trials. Carbamazepine and gabapentin appear to be the most promising adjunctive treatments for AWS, and they may be useful as monotherapy in select cases, especially in outpatient settings and for the treatment of mild-to-moderate low-risk patients with the AWS. The body of evidence supporting the use of the NBACs for reducing harmful drinking in the outpatient setting is stronger. Topiramate appears to have a robust effect on reducing harmful drinking in alcoholics. Gabapentin is a potentially efficacious treatment for reducing the risk of relapse to harmful drinking patterns in outpatient management of alcoholism. Gabapentin's ease of use, rapid titration, good tolerability, and efficacy in both the withdrawal and chronic phases of treatment make it particularly appealing. In summary, several NBACs appear to be beneficial in treating AWS and alcohol use disorders.

Topiramate impairs cognitive function in methadone-maintained individuals with concurrent cocaine dependence

Topiramate is being investigated as a potential pharmacotherapy for the treatment of addictive disorders. However, its cognitive side effects raise concerns about its use, especially in populations with cognitive impairment, such as persons with chronic substance use disorders. This study investigated topiramate's cognitive effects in individuals dually dependent on cocaine and opioids as part of a double-blind, randomized, controlled trial of topiramate for cocaine dependence treatment. After 5 weeks of stabilization on daily oral methadone (M = 96 mg), participants were randomized to topiramate (n = 18) or placebo (n = 22). Cognitive testing took place at 2 time points: study weeks 4 through 5 to assess baseline performance and 10 to 13 weeks later to assess performance during stable dosing (300 mg topiramate or placebo). All participants were maintained on methadone at both testing times, and testing occurred 2 hours after the daily methadone plus topiramate/placebo administration. The topiramate and placebo groups did not differ on sex, level of education, premorbid intelligence, methadone dose, or illicit drug use. Topiramate slowed psychomotor and information processing speed, worsened divided attention, reduced n-back working memory accuracy, and increased the false alarm rate in recognition memory. Topiramate had no effects on visual processing, other measures of psychomotor function, risk-taking, self-control, Sternberg working memory, free recall, and metamemory. These findings indicate that topiramate may cause cognitive impairment in this population. This effect may limit its acceptability and use as a treatment in individuals with chronic opioid and cocaine use disorders, among whom preexisting cognitive impairments are common. (PsycINFO Database Record