The clinical pharmacology of acamprosate

Modulation of Binge-like Ethanol Consumption by IL-10 Signaling in the Basolateral Amygdala

Excessive ethanol consumption alters the neuroimmune system and particularly impacts the cytokine milieu of the CNS. Cytokine dysregulation has been shown to underlie addictive-like behaviors including alcohol abuse; however, many studies focus primarily on the proinflammatory cytokine profile during alcohol dependence. The current study furthers this research by determining the impact of excessive ethanol consumption on interleukin-10 (IL-10) and interleukin-4 (IL-4) activity in a model of non-dependent binge consumption called the "drinking in the dark" (DID) paradigm. Furthermore, the ability of IL-10 to modulate ethanol consumption was tested using site-directed pharmacology. Immunohistochemistry analyses determined that ethanol decreased IL-10 by 50 % in the basolateral amygdala (BLA) but had no effect on IL-4. Neither IL-10 nor IL-4, however, were altered in the central amygdala (CEA). Enzyme linked immunosorbent assays confirmed that IL-10 was decreased in the amygdala but not in the serum, suggesting changes of this cytokine with the DID paradigm are restricted to the central nervous system. Finally, bilateral infusions of IL-10 into the BLA, but not CeA, reduced binge-like drinking and corresponding blood ethanol concentrations without impacting either locomotor activity or anxiety-like behavioral correlates. Together, these data support the idea that alcohol abuse dysregulates specific anti-inflammatory cytokines; however, ameliorating alcohol-induced effects on cytokines, like IL-10, may prove to be an effective therapy in curbing excessive consumption.

Review article: pharmacotherapy for alcohol dependence - the why, the what and the wherefore

BACKGROUND

The development of alcohol dependence is associated with significant morbidity and mortality. For the majority of affected people the most appropriate goal, in terms of drinking behaviour, is abstinence from alcohol. Psychosocial intervention is the mainstay of the treatment but adjuvant pharmacotherapy is also available and its use recommended.

AIM

To provide an updated analysis of current and potential pharmacotherapeutic options for the management of alcohol dependence. In addition, factors predictive of therapeutic outcome, including compliance and pharmacogenetics, and the current barriers to treatment, including doctors' unwillingness to prescribe these agents, will be explored.

METHODS

Relevant papers were selected for review following extensive, language- and date-unrestricted, electronic and manual searches of the literature.

RESULTS

Acamprosate and naltrexone have a substantial evidence base for overall efficacy, safety and cost-effectiveness while the risks associated with the use of disulfiram are well-known and can be minimised with appropriate patient selection and supervision. Acamprosate can be used safely in patients with liver disease and in those with comorbid mental health issues and co-occurring drug-related problems. A number of other agents are being investigated for potential use for this indication including: baclofen, topiramate and metadoxine.

CONCLUSION

Pharmacotherapy for alcohol dependence has been shown to be moderately efficacious with few safety concerns, but it is substantially underutilised. Concerted efforts must be made to remove the barriers to treatment in order to optimise the management of people with this condition.

Alcohol-related cognitive impairment: current trends and future perspectives

Excessive alcohol use is associated with a wide range of physical, psychological and social consequences, and is responsible for a significant proportion of the burden of disease globally. An area which has received increasing interest is alcohol-related brain damage, not just because of the cost to the individual and society through resource utilization, but also because of the potential for prevention and reversibility. This paper aims to review the current literature on this subject and seeks to explore issues around diagnosis and treatment of alcohol-related brain damage.

Pharmacological Modulation of GABA Function in Autism Spectrum Disorders: A Systematic Review of Human Studies

Autism spectrum disorders are an emerging health problem worldwide, but little is known about their pathogenesis. It has been hypothesized that autism may result from an imbalance between excitatory glutamatergic and inhibitory GABAergic pathways. Commonly used medications such as valproate, acamprosate, and arbaclofen may act on the GABAergic system and be a potential treatment for people with ASD. The present systematic review aimed at evaluating the state-of-the-art of clinical trials of GABA modulators in autism. To date there is insufficient evidence to suggest the use of these drugs in autistic subjects, even if data are promising. Of note, short-term use of all the reviewed medications appears to be safe. Future well designed trials are needed to elucidate these preliminary findings.

Acamprosate: A Review of Its Use in Alcohol Dependence

Acamprosate (Campral(®), Aotal(®), Regtect(®)) is one of a limited number of pharmacological treatment options approved as an adjunct to psychosocial interventions to facilitate the maintenance of abstinence in alcohol-dependent patients. It has been used in Europe, the USA and other countries for many years and was recently approved for this indication in Japan. In several randomized, double-blind, placebo-controlled trials (without active comparators), acamprosate in conjunction with psychosocial therapy for 3-12 months was generally significantly better than placebo plus psychosocial interventions in improving various key outcomes, including the proportion of patients who maintained complete abstinence from alcohol (complete abstinence rate), the mean cumulative abstinence duration, the percentage of alcohol-free days and the median time to first drink. Acamprosate as an adjunct to psychosocial interventions also demonstrated efficacy in some randomized, active-comparator trials of similar duration. Although results were not always consistent across individual trials, overall findings were generally favourable for acamprosate in a recent meta-analysis, which showed that alcohol-consumption outcomes were similarly improved with acamprosate or naltrexone. Acamprosate is generally well tolerated, has a low propensity for drug interactions and may be used without dosage adjustment in patients with mild to moderate hepatic impairment, although dosage adjustments or contraindications are recommended in patients with renal impairment. Thus, the use of acamprosate as an adjunct to psychosocial interventions in alcohol-dependent patients provides modest but potentially valuable improvements in alcohol-consumption outcomes and is generally well tolerated.

Pharmacogenetics of alcohol use disorders and comorbid psychiatric disorders

Alcohol use disorders (AUDs) represent a significant health burden worldwide. Currently, there are three medications approved by the U.S. Food and Drug Administration for the treatment of AUDs, and other drugs are being prescribed off-label for this purpose. However, response rates for pharmacologic treatment are low, and extant research suggests that treatment effects may partially depend on genetic factors. Personalized medicine, or using a patient's genetics and/or personal history to determine efficacy of treatment prior to prescription, is an emerging tool that will help clinicians treat their patients more effectively and safely. This review systematically discusses current findings from AUD pharmacotherapy trials examining disulfiram, acamprosate, naltrexone, the injectable naltrexone, and topiramate. Furthermore, it presents pharmacogenetics findings associated with these medications in an attempt to further the field of personalized medicine. Research from trials examining AUDs and comorbid major depressive disorder and anxiety disorders is also presented, and pharmacogenetic findings for these treatments are discussed. Lastly, the authors comment on the present and future states of the field of personalized medicine for AUD.

The indirect NMDAR antagonist acamprosate induces postischemic neurologic recovery associated with sustained neuroprotection and neuroregeneration

Cerebral ischemia stimulates N-methyl-d-aspartate receptors (NMDARs) resulting in increased calcium concentration and excitotoxicity. Yet, deactivation of NMDAR failed in clinical studies due to poor preclinical study designs or toxicity of NMDAR antagonists. Acamprosate is an indirect NMDAR antagonist used for patients with chronic alcohol dependence. We herein analyzed the therapeutic potential of acamprosate on brain injury, neurologic recovery and their underlying mechanisms. Mice were exposed to cerebral ischemia, treated with intraperitoneal injections of acamprosate or saline (controls), and allowed to survive until 3 months. Acamprosate yielded sustained neuroprotection and increased neurologic recovery when given no later than 12 hours after stroke. The latter was associated with increased postischemic angioneurogenesis, albeit acamprosate did not stimulate angioneurogenesis itself. Rather, increased angioneurogenesis was due to inhibition of calpain-mediated pro-injurious signaling cascades. As such, acamprosate-mediated reduction of calpain activity resulted in decreased degradation of p35, increased abundance of the pro-survival factor STAT6, and reduced N-terminal-Jun-kinase activation. Inhibition of calpain was associated with enhanced stability of the blood-brain barrier, reduction of oxidative stress and cerebral leukocyte infiltration. Taken into account its excellent tolerability, its sustained effects on neurologic recovery, brain tissue survival, and neural remodeling, acamprosate is an intriguing candidate for adjuvant future stroke treatment.

The pharmacogenetics of alcohol use disorder

BACKGROUND

Annually, the use and abuse of alcohol contributes to millions of deaths and billions of dollars in societal costs. To determine the impact of genetic variation on the susceptibility to the disorder and its response to treatment, studies have been conducted to assess the contribution of a variety of candidate genetic variants. These variants, which we review here, were chosen based upon their observed or hypothesized functional relevance to alcohol use disorder (AUD) risk or to the mechanism by which medications used to treat the disorder exert their effects.

METHODS

This qualitative review examines studies in which candidate polymorphisms were tested as moderator variables to identify pharmacogenetic effects on either the subjective response to alcohol or the outcomes of pharmacotherapy.

RESULTS

Although findings from these studies provide evidence of a number of clinically relevant pharmacogenetic effects, the literature is limited and there are conflicting findings that require resolution.

CONCLUSIONS

Pharmacogenetic studies of AUD treatment that use greater methodological rigor and better statistical controls, such as corrections for multiple testing, may help to resolve inconsistent findings. These procedures could also lead to the discovery of more robust and clinically meaningful moderator effects. As the field evolves through methodological standardization and the use of larger study samples, pharmacogenetic research has the potential to inform clinical care by enhancing therapeutic effects and personalizing treatments. These efforts may also provide insights into the mechanisms by which medications reduce heavy drinking or promote abstinence in patients with an AUD.

Advances in Medications and Tailoring Treatment for Alcohol Use Disorder

Alcohol use disorder (AUD) is a chronic heritable brain disorder with a variable clinical presentation. This variability, or heterogeneity, in clinical presentation suggests complex interactions between environmental and biological factors, resulting in several underlying pathophysiological mechanisms in the development and progression of AUD. Classifying AUD into subgroups of common clinical or pathological characteristics would ease the complexity of teasing apart underlying molecular mechanisms. Genetic association analyses have revealed several polymorphisms-small differences in DNA-that increase a person's vulnerability to develop AUD and other alcohol-related intermediate characteristics, such as severity of drinking, age of AUD onset, or measures of craving. They also have identified polymorphisms associated with reduced drinking. Researchers have begun utilizing these genetic polymorphisms to identify alcoholics who might respond best to various treatments, thereby enhancing the effectiveness of currently tested medications for treating AUD. This review compares the efficacy of medications tested for treatment of AUD with and without incorporating genetics. It then discusses advances in pre-clinical genetic and genomic studies that potentially could be adapted to clinical trials to improve treatment efficacy. Although a pharmacogenetic approach is promising, it is relatively new and will need to overcome many challenges, including inadequate scientific knowledge and social and logistic constraints, to be utilized in clinical practice.

Childhood maltreatment, stressful life events, and alcohol craving in adult drinkers

BACKGROUND

Little is known about the relationship between stressful life events and alcohol craving in the general population, and whether a history of childhood maltreatment sensitizes individuals to crave alcohol after adult stressors.

METHODS

Participants were 22,147 past-year drinkers from Wave 2 (2004 to 2005) of the National Epidemiologic Survey on Alcohol and Related Conditions. A structured, face-to-face interview assessed past-year stressful life events, alcohol craving, and history of childhood maltreatment. Logistic regression was used to generate adjusted odds ratios (aOR) to evaluate the relationship between stressful life events and craving, adjusting for demographic characteristics and parental history of alcoholism. Interaction between stressful life events and childhood maltreatment was also assessed.

RESULTS

Compared to participants with no stressful life events, those with ≥ 3 events had increased odds of moderate alcohol craving (aOR = 3.15 [95% CI = 2.30 to 4.33]) and severe craving (aOR = 8.47 [95% CI = 4.78 to 15.01]). Stressful life events and childhood maltreatment interacted in predicting severe craving (p = 0.017); those with ≥ 3 events were at higher risk of craving if they had been exposed to childhood maltreatment.

CONCLUSIONS

A direct relationship between stressful life events and risk of alcohol craving was observed. Further, history of childhood maltreatment increased the salience of stressful life events in adulthood. Future studies should examine the role of psychiatric comorbidity in more complex models of stress sensitization and alcohol craving.