Helen M. Pettinati

A Functional Polymorphism of the μ -Opioid Receptor Gene is Associated with Naltrexone Response in Alcohol-Dependent Patients

This study examined the association between two specific polymorphisms of the gene encoding the μ-opioid receptor and treatment outcomes in alcohol-dependent patients who were prescribed naltrexone or placebo. A total of 82 patients (71 of European descent) who were randomized to naltrexone and 59 who were randomized to placebo (all of European descent) in one of three randomized, placebo-controlled clinical trials of naltrexone were genotyped at the A+118G (Asn40Asp) and C+17T (Ala6Val) SNPs in the gene encoding the μ-opioid receptor (OPRM1). The association between genotype and drinking outcomes was measured over 12 weeks of treatment. In subjects of European descent, individuals with one or two copies of the Asp40 allele treated with naltrexone had significantly lower rates of relapse (p=0.044) and a longer time to return to heavy drinking (p=0.040) than those homozygous for the Asn40 allele. There were no differences in overall abstinence rates (p=0.611), nor were there differences in relapse rates or abstinence rates between the two genotype groups among those assigned to placebo. These preliminary results are consistent with prior literature demonstrating that the opioid system is involved in the reinforcing properties of alcohol and that allelic variation at OPRM1 is associated with differential response to a μ-receptor antagonist. If replicated, these results would help to identify alcohol-dependent individuals who may be most likely to respond to treatment with naltrexone.

An Evaluation of μ-Opioid Receptor (OPRM1) as a Predictor of Naltrexone Response in the Treatment of Alcohol Dependence: Results From the Combined Pharmacotherapies and Behavioral Interventions for Alcohol Dependence (COMBINE) Study

CONTEXT Naltrexone hydrochloride treatment for alcohol dependence works for some individuals but not for everyone. Asn40Asp, a functional polymorphism of the mu-opioid receptor gene (OPRM1), might predict naltrexone response. OBJECTIVE To evaluate whether individuals with alcoholism who are heterozygous (Asp40/Asn40) or homozygous (Asp40/Asp40) for the OPRM1 Asp40 allele respond better to naltrexone. DESIGN Pharmacogenetic analysis conducted between January 1, 2001, and January 31, 2004. SETTING Eleven academic sites in the COMBINE Study. PARTICIPANTS Recently abstinent volunteers who met all 3 of the following conditions: (1) DSM-IV criteria for primary alcohol dependence; (2) participation in the COMBINE Study; and (3) availability of DNA. INTERVENTIONS Alcoholic subjects were treated for 16 weeks with 100 mg of naltrexone hydrochloride (234 Asn40 homozygotes and 67 with at least 1 copy of the Asp40 allele) or placebo (235 Asn40 homozygotes and 68 with at least 1 copy of the Asp40 allele). All participants received medical management (MM) alone or with combined behavioral intervention (CBI). MAIN OUTCOME MEASURES Time trends in percentage of days abstinent, percentage of heavy drinking days, and rates of good clinical outcome. RESULTS Alcoholic subjects with an Asp40 allele receiving MM alone (no CBI) had an increased percentage of days abstinent (P = .07) and a decreased percentage of heavy drinking days (P = .04) if treated with naltrexone vs placebo, while those with the Asn40/Asn40 genotype showed no medication differences. If treated with MM alone and naltrexone, 87.1% of Asp40 carriers had a good clinical outcome, compared with only 54.8% of individuals with the Asn40/Asn40 genotype (odds ratio, 5.75; confidence interval, 1.88-17.54), while, if treated with placebo, 48.6% of Asp40 carriers and 54.0% of individuals with the Asn40/Asn40 genotype had a good clinical outcome (interaction between medication and genotype, P = .005). No gene x medication interactions were observed in those treated with both MM and CBI. CONCLUSIONS These results confirm and extend the observation that the functionally significant OPRM1 Asp40 allele predicts naltrexone treatment response in alcoholic individuals. This relationship might be obscured, however, by other efficacious treatments. OPRM1 genotyping in alcoholic individuals might be useful to assist in selecting treatment options. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00006206.

A Double-Blind, Placebo-Controlled Trial of Modafinil for Cocaine Dependence

Despite years of active research, there are still no approved medications for the treatment of cocaine dependence. Modafinil is a glutamate-enhancing agent that blunts cocaine euphoria under controlled conditions, and the current study assessed whether modafinil would improve clinical outcome in cocaine-dependent patients receiving standardized psychosocial treatment. This was a randomized, double-blind, placebo-controlled trial conducted at a university outpatient center (from 2002 to 2003) on a consecutive sample of 62 (predominantly African American) cocaine-dependent patients (aged 25–63) free of significant medical and psychiatric conditions. After screening, eligible patients were randomized to a single morning dose of modafinil (400 mg), or matching placebo tablets, for 8 weeks while receiving manual-guided, twice-weekly cognitive behavioral therapy. The primary efficacy measure was cocaine abstinence based on urine benzoylecgonine levels. Secondary measures were craving, cocaine withdrawal, retention, and adverse events. Modafinil-treated patients provided significantly more BE-negative urine samples (p=0.03) over the 8-week trial when compared to placebos, and were more likely to achieve a protracted period (⩾3 weeks) of cocaine abstinence (p=0.05). There were no serious adverse events, and none of the patients failed to complete the study as a result of adverse events. This study provides preliminary evidence, which should be confirmed by a larger study, that modafinil improves clinical outcome when combined with psychosocial treatment for cocaine dependence.

Predicting treatment response to naltrexone: the influence of craving and family history.

Naltrexone has repeatedly been shown to reduce drinking in alcohol-dependent patients. Previous clinical research suggests that naltrexone may be more effective at reducing drinking among patients with high levels of alcohol craving at the beginning of treatment. In addition, laboratory studies suggest that naltrexone may be more efficacious among patients with a high familial loading of alcohol problems. We explored both of these possibilities in the context of the first 12-week phase of a double blind, placebo-controlled naltrexone trial. A total of 121 patients were randomized to receive 100 mg/day naltrexone and 62 patients were randomized to receive placebo. Both naltrexone and placebo were given in conjunction with a psychosocial intervention designed to be integrated with the use of pharmacotherapy. This intervention was administered by nurse practitioners. Overall, patients randomized to naltrexone reported drinking five or more drinks on fewer days than did placebo controls (p = .04). Interactions were observed between medication group assignment and both craving level prior to randomization (p = .02) and family loading of alcohol problems (p = .05). In both cases, the interaction was in the predicted direction. These data suggest that patients with high levels of alcohol craving or a strong family history of alcoholism are more likely to benefit from naltrexone treatment.

A Double-Blind, Placebo-Controlled Trial Combining Sertraline and Naltrexone for Treating Co-Occurring Depression and Alcohol Dependence

OBJECTIVE Empirical evidence has only weakly supported antidepressant treatment for patients with co-occurring depression and alcohol dependence. While some studies have demonstrated that antidepressants reduce depressive symptoms in individuals with depression and alcohol dependence, most studies have not found antidepressant treatment helpful in reducing excessive drinking in these patients. The authors provide results from a double-blind, placebo-controlled trial that evaluated the efficacy of combining approved medications for depression (sertraline) and alcohol dependence (naltrexone) in treating patients with both disorders. METHOD A total of 170 depressed alcohol-dependent patients were randomly assigned to receive 14 weeks of treatment with sertraline (200 mg/day [N=40]), naltrexone (100 mg/day [N=49]), the combination of sertraline plus naltrexone (N=42), or double placebo (N=39) while receiving weekly cognitive-behavioral therapy. RESULTS The sertraline plus naltrexone combination produced a higher alcohol abstinence rate (53.7%) and demonstrated a longer delay before relapse to heavy drinking (median delay=98 days) than the naltrexone (abstinence rate: 21.3%; delay=29 days), sertraline (abstinence rate: 27.5%; delay=23 days), and placebo (abstinence rate: 23.1%; delay=26 days) groups. The number of patients in the medication combination group not depressed by the end of treatment (83.3%) approached significance when compared with patients in the other treatment groups. The serious adverse event rate was 25.9%, with fewer reported with the medication combination (11.9%) than the other treatments. CONCLUSIONS More depressed alcohol-dependent patients receiving the sertraline plus naltrexone combination achieved abstinence from alcohol, had delayed relapse to heavy drinking, reported fewer serious adverse events, and tended to not be depressed by the end of treatment.

Improving naltrexone response: an intervention for medical practitioners to enhance medication compliance in alcohol dependent patients.

Abstract The effectiveness of naltrexone, a FDA-approved medication for alcohol dependence, can be improved if we support and help patients to consistently take their medication. We illustrate how patient noncompliance with treatment negatively affects outcome, and, we describe a new intervention to enhance medication compliance. Outcome was evaluated for 196 alcohol dependent outpatients who were treated with 50 mg/day naltrexone or placebo for 12 weeks. For patients who adhered to the prescribed treatment, relapse rates were lower with naltrexone than placebo (10% vs. 38.6%, p< 0.001). For noncompliant patients, relapse rates were high and comparable between naltrexone-and placebo-treated patients (42.9% vs. 40%). In a second study of 100 alcohol dependent outpatients, we introduced an intervention that resulted in better medication compliance rates compared to a previous naltrexone study of patients who did not receive the intervention (77.0% vs. 60.8%, p< 0.01). This provided some support for the use of an intervention that targets medication compliance when prescribing nal-trexone.

Alcoholism Treatment Adherence: Older Age Predicts Better Adherence and Drinking Outcomes

OBJECTIVE Adherence to treatment has been demonstrated to be an important factor for remission from alcohol dependence. The authors compared therapy and medication adherence for treatment of alcohol dependence in older adults with adherence in younger adults. METHODS All subjects were participants in a randomized, double-blind, placebo-controlled efficacy trial of naltrexone for the treatment of alcohol dependence. All subjects received a medically-based psychosocial intervention focused on motivating patients to change and on adherence to treatment. The therapy is nonconfrontational and is delivered by a nurse-practitioner. RESULTS Compared with younger adults, older adults had greater attendance at therapy sessions and greater adherence to the medication. Age-group was the only pretreatment factor associated with adherence. The greater adherence in older adults translated to less relapse than in younger adults. CONCLUSION Treatment for alcohol dependence can be effective for older adults. Older adults appear to respond well to a medically-oriented program that is supportive and individualized. In fact, findings from this study suggest that older adults can be treated in mixed-age treatment settings when psychotherapeutic strategies are used that are age-appropriate and delivered on an individual basis.

Current status of co-occurring mood and substance use disorders: a new therapeutic target.

Mood and substance use disorders commonly co-occur, yet there is little evidence-based research to guide the pharmacologic management of these comorbid disorders. The authors review the existing empirical findings, some of which may call into question current clinical pharmacotherapy practices for treating co-occurring mood and substance use disorders. The authors also highlight knowledge gaps that can serve as a basis for future research. The specific mood disorders reviewed are bipolar and major depressive disorders (either one co-occurring with a substance use disorder). Overall, findings from the relatively small amount of available data indicate that pharmacotherapy for managing mood symptoms can be effective in patients with substance dependence, although results have not been consistent across all studies. Also, in most studies, medications for managing mood symptoms did not appear to have an impact on the substance use disorder. In a recent trial for comorbid major depression and alcohol dependence, combination treatment with a medication for depression and another for alcohol dependence was found to reduce depressive symptoms and excessive drinking simultaneously. However, research has only begun to address optimal pharmacologic management of co-occurring disorders. In addition, current clinical treatment for alcohol and drug dependence often excludes new pharmacotherapies approved by the U.S. Food and Drug Administration for treating certain types of addiction. With new data becoming available, it appears that we need to revisit current practice in the pharmacological management of co-occurring mood and substance use disorders.

Double-blind Clinical Trial of Sertraline Treatment for Alcohol Dependence

Clinical studies that have evaluated serotonergic medications to reduce alcohol consumption have yielded conflicting results. These studies primarily treated patients with alcohol dependence, excluding those with a current depressive disorder, in an effort to differentiate any medication effects directly on drinking from those on mood. Yet despite the exclusion of current depression, a group of alcohol-dependent patients who are not depressed can be highly heterogeneous. For example, this subgroup can include those with a lifetime depressive disorder. If these patients were more sensitive to serotonergic medications than patients without a lifetime depressive disorder, medication effects in a subgroup of patients who were not depressed could be obscured. Thus, the purpose of this study was to examine the efficacy of sertraline for treating alcohol dependence in patient groups that were differentiated by the presence or absence of lifetime depression. This study examined the effectiveness of sertraline (200 mg/day) or placebo for 14 weeks in 100 alcohol-dependent subjects with (N = 53) or without (N = 47) a lifetime diagnosis of comorbid depression. Sertraline treatment seemed to provide an advantage in reducing drinking in alcohol-dependent patients without lifetime depression, illustrated best with a measure of drinking frequency during treatment. However, sertraline was no better than placebo in patients with a diagnosis of lifetime comorbid depression, and current depression did not change the results. Treatment with selective serotonin reuptake inhibitors may be useful in alcohol-dependent patients who are not depressed. Subtyping those with alcohol dependence on the basis of the absence versus the presence of a lifetime depressive disorder may help to resolve conflicting findings in the literature on the treatment of alcohol dependence with serotonergic medications.

Antidepressant treatment of co-occurring depression and alcohol dependence

The use of antidepressant pharmacotherapy to treat patients with co-occurring depression and alcohol dependence is controversial. There is a stigma attached to giving medications to alcohol-dependent persons. Also, empirical evidence is sparse and inconsistent, which discourages the use of antidepressants in these patients. Historically, it has been a challenge to accurately diagnose a depressive disorder in the presence of alcohol dependence. In addition, early clinical studies were fraught with methodological problems; however, improved diagnostic assessments are now available, and in the last decade, results from well-controlled trials appear to support the use of antidepressants in this patient population in the specific role of relieving depressive symptoms. The majority of these trials also demonstrate that antidepressants have relatively little impact on reducing heavy drinking in this patient population, even though the medications reduce depressive symptoms. Newer approaches to treating patients with co-occurring depression and alcohol dependence suggest adding to the antidepressant a pharmacotherapy that directly impacts drinking. The findings from this review better define the action of antidepressants in patients with co-occurring depression and alcohol dependence as specific to reducing depressive symptoms, and these medications and their action on mood have little impact on treating the co-occurring alcohol dependence.