Raye Z. Litten

Medications development to treat alcohol dependence: a vision for the next decade

More than 76 million people world‐wide are estimated to have diagnosable alcohol use disorders (AUDs) (alcohol abuse or dependence), making these disorders a major global health problem. Pharmacotherapy offers promising means for treating AUDs, and significant progress has been made in the past 20 years. The US Food and Drug Administration approved three of the four medications for alcoholism in the last two decades. Unfortunately, these medications do not work for everyone, prompting the need for a personalized approach to optimize clinical benefit or more efficacious medications that can treat a wider range of patients, or both. To promote global health, the potential reorganization of the National Institutes of Health (NIH) must continue to support the National Institute on Alcohol Abuse and Alcoholisms (NIAAAs) vision of ensuring the development and delivery of new and more efficacious medications to treat AUDs in the coming decade. To achieve this objective, the NIAAA Medications Development Team has identified three fundamental long‐range goals: (1) to make the drug development process more efficient; (2) to identify more efficacious medications, personalize treatment approaches, or both; and (3) to facilitate the implementation and adaptation of medications in real‐world treatment settings. These goals will be carried out through seven key objectives. This paper describes those objectives in terms of rationale and strategy. Successful implementation of these objectives will result in the development of more efficacious and safe medications, provide a greater selection of therapy options and ultimately lessen the impact of this devastating disorder.

A Double-Blind, Placebo-Controlled Trial Assessing the Efficacy of Varenicline Tartrate for Alcohol Dependence

Objectives:To assess the efficacy and safety of varenicline (Chantix) for the treatment of alcohol dependence. Varenicline is a partial &agr;4&bgr;2 nicotinic acetylcholine agonist approved by the Food and Drug Administration for smoking cessation. It has reduced drinking in animal studies and in small studies of humans who were both heavy drinkers and smokers. This is the first multisite clinical trial of varenicline in a population of smokers and nonsmokers with alcohol dependence. Methods:Men and women (n = 200) meeting the criteria for alcohol dependence were recruited across 5 clinical sites. Patients received double-blind varenicline or placebo and a computerized behavioral intervention. Varenicline was titrated during the first week to 2 mg/d, which was maintained during weeks 2 to 13. Results:The varenicline group had significantly lower weekly percent heavy drinking days (primary outcome) (adjusted mean difference = 10.4), drinks per day, drinks per drinking day, and alcohol craving compared with the placebo group (P < 0.05). The average treatment effect on alcohol use was similar for smokers and nonsmokers. Varenicline was well-tolerated; adverse events were expected and mild. Conclusions:Varenicline significantly reduced alcohol consumption and craving, making it a potentially viable option for the treatment of alcohol dependence.

Craving research: future directions

Many prospective clinical studies have concluded that craving does not reliably predict relapse and that the concept is of little or no clinical utility. Contrary to earlier more simplistic clinical models of addiction, more recent models do not require that craving be present for relapse to occur. New approaches to study human craving may enhance its predictive validity and yield more knowledge of its nature, course, behavioural sequelae and regulatory function in alcohol/drug consumption. These approaches include empirical research that focuses on: (1) the elucidation of the domains of craving (i.e. subjective experience, physiological responses, behavioural sequelae and their inter-relationships); (2) the temporal dynamics of craving (i.e. its course over minutes or days, as well as its natural history over the course of a drinking career); (3) the factors that may mediate/moderate/determine the development and resolution of craving; (4) studies of the predictive validity of craving measures; and (5) the development of valid methods of measuring the different domains of craving. The conclusions are that future craving research should: (1) incorporate more sophisticated general theories of behaviour (conditioning, cognitive social learning, neurobiological, and genetic); (2) apply more sophisticated and standardized measurement methods and experimental paradigms, including studies in which alcohol is made available to human subjects; and (3) effective development of new pharmacological and behavioural therapies for relapse prevention depend on greater understanding of the nature and measurement of craving.

Percentage of Subjects With No Heavy Drinking Days: Evaluation as an Efficacy Endpoint for Alcohol Clinical Trials

BACKGROUND Percent subjects with no heavy drinking days (PSNHDDs), an efficacy end point recommended by the Food and Drug Administration, considers abstinent individuals or those engaging in low-risk drinking behavior as successful responders to treatment. As PSNHDD has been used infrequently in previous alcohol clinical trials, we evaluated the utility and validity of the PSNHDD outcome measure in 2 large alcohol clinical trials. METHODS Data sets from 2 alcohol trials, COMBINE and a multisite topiramate trial, were used to analyze PSNHDDs and other traditional end points for the topiramate, naltrexone, acamprosate, and placebo groups. Effect sizes of PSNHDDs were determined for each month of active treatment and by varying grace periods-early periods in the trial where outcome is not considered in the analysis-and were compared with that of other traditional outcome measures. Long-term outcomes were compared for groups that had no heavy drinking days versus those that had heavy drinking days during active treatment. RESULTS PSNHDD effect sizes were significant for both topiramate (0.34 and 0.25 at months 2 and 3, respectively) and naltrexone (0.24 and 0.26 at months 3 and 4, respectively). Given a 2-month grace period for naltrexone, the effect size of PSNHDDs was comparable to the effect sizes using traditional outcome measures. With a 1-month grace period for topiramate, it was greater than the majority of traditional outcome measures. Little is gained by allowing up to 1, 2, or 3 heavy drinking days as an end point. Subjects with no HDDs during treatment fared better than those with some HDDs on drinking outcomes and alcohol-related consequences during a 1-year follow-up. CONCLUSIONS PSNHDD appears to be a clinically informative end point measure, especially when used with a grace period, and is as sensitive as most traditional outcome measures in detecting differences between the medication and placebo groups. Nonetheless, these findings should be replicated in other clinical data sets, particularly with medications that work via different mechanisms.

Alcohol biomarkers in applied settings: recent advances and future research opportunities.

During the past decade, advances have been made in the identification, development, and application of alcohol biomarkers. This is important because of the unique functions that alcohol biomarkers can serve in various applied settings. To carry out these functions, biomarkers must display several features including validity, reliability, adequacy of temporal window of assessment, reasonable cost, and transportability. During the past two decades, several traditional alcohol biomarkers have been studied in multiple human studies. Meanwhile, several new, promising biomarkers, including various alcohol metabolites and alcohol biosensors, are being explored in human studies. In addition, researchers have explored using biomarkers in combination and using biomarkers in combination with self-reports, resulting in increased sensitivity with little sacrifice in specificity. Despite these advances, more research is needed to validate biomarkers, especially the new ones, in humans. Moreover, recent advances in high-throughput technologies for genomics, proteomics, and metabolomics offer unique opportunities to discover novel biomarkers, while additional research is needed to perfect newly developed alcohol sensors. Development of more accurate biomarkers will help practicing clinicians to more effectively screen and monitor individuals who suffer from alcohol use disorders.

Heterogeneity of Alcohol Use Disorder: Understanding Mechanisms to Advance Personalized Treatment

THROUGHOUT THE DECADES, addiction has been viewed as a dichotomous entity-a patient either had or did not have the disorder, with nothing in-between (Miller, 1996). With research, however, it is becoming increasingly clear that alcohol use disorder (AUD) is, in fact, heterogeneous. Each patient develops an AUD based on his or her unique neurobiological makeup and lifetime experiences—a complex interaction of underlying genetic and environmental mechanisms (Dick and Kendler, 2012). This heterogeneity manifests in a continuum of severity, ranging from the occasional binge drinker to the chronic relapsing heavy drinker. This heterogeneity can be understood as a number of subphenotypes, each having its own unique profile of drinking pattern, motivation for drinking, alcohol-related consequences, and neurobiological underpinnings. Not surprisingly, given its heterogeneity, a wide variety of clinically acceptable treatment outcomes are possible with AUD, including not only abstinence, but also low-risk drinking (and even some less-conservative forms of moderate drinking; Dawson et al., 2005; Willenbring et al., 2009). This has resulted in a menu of effective treatment options (O’Malley and O’Connor, 2011; Witkiewitz and Marlatt, 2011). The U.S. Food and Drug Administration has approved 3 medications to treat alcohol dependence—disulfiram, oral and injectable naltrexone, and acamprosate—and nalmefene was approved last year by the European Medicines Agency (Mann et al., 2013; O’Malley and O’Connor, 2011). A variety of behavioral therapies have also been shown to be effective, including cognitive-behavioral therapy (CBT), motivational enhancement therapy (MET), 12-step facilitation therapy (TSF), contingency management, brief behavioral intervention, behavioral couples/family therapy, and the community reinforcement approach (Fuller and HillerSturmhoefel, 1999; Miller and Meyers, 1999; Witkiewitz and Marlatt, 2011). Unfortunately, despite the proven efficacy of these treatment approaches, given the heterogeneity of AUD, no one treatment will work for every person suffering from this complex disorder.

Advances in development of medications for alcoholism treatment

Abstract Over the past decade, research on medications to treat alcohol problem has flourished. Naltrexone and acamprosate are tangible fruits of such endeavors and each has now earned approval in a large number of countries. Recent studies on naltrexone indicate that patient compliance is important if full benefits are to be achieved. Several laboratory studies with human subjects are beginning to elucidate the mechanisms underlying efficacy of naltrexone, as well as explaining variability of response among subpopulations of drinkers. In addition to these two agents, recent investigations have also demonstrated that the antidepressants desipramine, imipramine, and fluoxetine reduce mood-related symptoms and, to some extent, drinking itself in alcoholics who are depressed. Research to date suggests that opioid antagonists and selective serotonin reuptake inhibitors are more effective in reducing alcohol intake when used in combination. Clinical issues, methodology, and directions for future research are also reviewed in this article. In particular, issues addressed include alternative dosage regimens, necessary duration of treatment, employment of medications in combination, integration of pharmacologic agents with behavioral interventions, enhancement of patient compliance, and concurrent treatment of psychiatric comorbidity.

The role of laboratory tests in alcoholism treatment.

Although assessment in the field of alcoholism treatment is generally verbal in nature, biological tests can also provide counselors and program evaluators useful and unique information. Five such laboratory measures are briefly described, with particular emphasis on carbohydrate deficient transferrin, a biomarker recently approved by the FDA. Applications for laboratory tests in alcohol screening, motivating patients, and monitoring treatment progress are also proposed.

A Double-Blind, Placebo-Controlled Trial to Assess the Efficacy of Quetiapine Fumarate XR in Very Heavy-Drinking Alcohol-Dependent Patients

BACKGROUND Despite advances in developing medications to treat alcohol dependence, few such medications have been approved by the Food and Drug Administration. Identified molecular targets are encouraging and can lead to the development and testing of new compounds. Atypical antipsychotic medications have been explored with varying results. Prior research suggests that the antipsychotic quetiapine may be beneficial in an alcohol-dependent population of very heavy drinkers. METHODS In this double-blind, placebo-controlled trial, 224 alcohol-dependent patients who reported very heavy drinking were recruited across 5 clinical sites. Patients received either quetiapine or placebo and Medical Management behavioral intervention. Patients were stratified on gender, clinical site, and reduction in drinking prior to randomization. RESULTS No differences between the quetiapine and placebo groups were detected in the primary outcome, percentage heavy-drinking days, or other drinking outcomes. Quetiapine significantly reduced depressive symptoms and improved sleep but had no effect on other nondrinking outcomes. Results from a subgroup analysis suggest that patients who reduced their drinking prior to randomization had significantly better drinking outcomes during the maintenance phase (p < 0.0001). No significant interactions, however, were observed between reducer status and treatment group. Finally, quetiapine was generally well tolerated. Statistically significant adverse events that were more common with quetiapine versus placebo include dizziness (14 vs. 4%), dry mouth (32 vs. 9%), dyspepsia (13 vs. 2%), increased appetite (11 vs. 1%), sedation (15 vs. 3%), and somnolence (34 vs. 9%). CONCLUSIONS This multisite clinical trial showed no efficacy for quetiapine compared with placebo at reducing alcohol consumption in heavy-drinking alcohol-dependent patients.

Pharmacological Treatment of Alcohol Abuse/Dependence With Psychiatric Comorbidity

This article represents the proceedings of a symposium at the 2003 annual meeting RSA in Fort Lauderdale, FL. It was organized and cochaired by Charlene E. Le Fauve and Carrie L. Randall. The presentations were (1) Introduction, by Charlene E. Le Fauve and Raye Z. Litten; (2) Treatment of co-occurring alcohol use and anxiety disorders, by Carrie L. Randall and Sarah W. Book; (3) Pharmacological treatment of alcohol dependent patients with comorbid depression, by Darlene H. Moak; (4) Efficacy of valproate in bipolar alcoholics: a double blind, placebo-controlled study, by Ihsan M. Salloum, Jack R. Cornelius, Dennis C. Daley, Levent Kirisci, Johnathan Himmelhoch, and Michael E. Thase; (5) Alcoholism and schizophrenia: effects of antipsychotics, by Alan I. Green, Robert E. Drake, Suzannah V. Zimmet, Rael D. Strous, Melinda Salomon, and Mark Brenner; and (6) Conclusions, by Charlene E. Le Fauve; discussant, Raye Z. Litten. Alcohol-dependent individuals have exceptionally high rates of co-occurring psychiatric disorders. Although this population is more likely to seek alcoholism treatment than noncomorbid alcoholics, the prognosis for treatment is often poor, particularly among patients with more severe psychiatric illnesses. Development of effective interventions to treat this population is in the early stages of research. Although the interaction between the psychiatric condition and alcoholism is complex, progress has been made. The NIAAA has supported a number of state-of-the-art pharmacological and behavioral trials in a variety of comorbid psychiatric disorders. Some of these trials have been completed and are presented here. The symposium presented some new research findings from clinical studies with the aim of facilitating the development of treatments that improve alcohol and psychiatric outcomes among individuals with alcohol-use disorders and co-occurring psychiatric disorders. The panel focused on social anxiety disorder, depression, bipolar disorder, and schizophrenia.