Opioid and Dopamine Genes Interact to Predict Naltrexone Response in a Randomized Alcohol Use Disorder Clinical Trial.

BACKGROUND: While the opiate antagonist, naltrexone, is approved for treating alcohol use disorder (AUD), not everyone who receives the medication benefits from it. This study evaluated whether the OPRM1 SNP rs1799971 interacts with the dopamine transporter gene DAT1/SLC6A3 VNTR rs28363170 or the catechol-O-methyltransferase (COMT) gene SNP rs4680 in predicting naltrexone response. METHODS: Individuals who met DSM-IV alcohol dependence were randomly assigned to naltrexone (50 mg/d) or placebo based on their OPRM1 genotype (75 G-allele carriers and 77 A-allele homozygotes) and also genotyped for DAT1 VNTR (9 vs. 10 repeats) or COMT SNP (val/val vs. met carriers). Heavy drinking days (%HDD) were evaluated over 16 weeks and at the end of treatment. Effect sizes (d) for naltrexone response were calculated based on genotypes. RESULTS: Naltrexone, relative to placebo, significantly reduced %HDD among OPRM1 G carriers who also had DAT1 10/10 (p = 0.021, d = 0.72) or COMT val/val genotypes (p = 0.05, d = 0.80), and to a lesser degree in those OPRM1 A homozygotes who were also DAT1 9-repeat carriers (p = 0.09, d = 0.70) or COMT met carriers (p = 0.03, d = 0.63). All other genotype combinations showed no differential response to naltrexone. Diarrhea/abdominal pain was more prominent in OPRM1 A homozygotes who were also DAT 9 or COMT met carriers. CONCLUSIONS: These results suggest that individuals with AUD with a more opioid-responsive genotype (OPRM1 G carriers) respond better to naltrexone if they have genotypes indicating normal/less dopamine tone (DAT1 10,10 or COMT val,val), while those with a less responsive opioid-responsive genotype (OPRM1 A homozygotes) respond better to naltrexone if they have genotypes indicating greater dopamine tone (DAT1 9-repeat or COMT met carriers). These results could lead to more personalized AUD treatments.

Nicotine-Use/Smoking Is Associated with the Efficacy of Naltrexone in the Treatment of Alcohol Dependence.

BACKGROUND: The opioid antagonist naltrexone is not efficacious for every alcohol treatment seeker. However, various individual factors, such as genetic differences and nicotine-use/smoking status, have been suggested as predictors of naltrexone response. In a randomized clinical trial, we previously reported that nicotine-use/smoking status might be a stronger predictor of naltrexone efficacy than OPRM1 A118G single nucleotide polymorphism (SNP) genotype. In this report, we further characterize the nicotine-users in that trial, examine other drinking outcomes, examine the influence of smoking change on naltrexone effects on drinking, and validate the result in smokers with disialo carbohydrate-deficient transferrin (%dCDT) change as an independent biomarker of response. METHODS: Individuals (n = 146) meeting DSM-IV criteria for alcohol dependence who were genotyped for the OPRM1 A118G SNP and who did, or did not, use nicotine/cigarettes were randomized, in a balanced fashion, to naltrexone (50 mg/d) or placebo and provided medical management (MM) over a 16-week clinical trial. Alcohol use and smoking during the trial were assessed and analyzed. RESULTS: Nicotine-use/smoking status significantly interacted with medication in reducing percent heavy drinking days (PHDD) during the trial (p = 0.003), such that nicotine-users/smokers showed significantly lower PHDD on naltrexone versus placebo (p = 0.0001, Cohen's d = 0.89), while nonusers showed no significant difference between naltrexone and placebo (p = 0.95, Cohen's d = 0.02). Similar effects were shown for drinks per day and percent days drinking. The superiority of naltrexone over placebo on PHDD reduction in nicotine-users/smokers was confirmed with %dCDT (Cohen's d range 0.3 to 0.9 over the study). Naltrexone did not significantly change cigarette use in smokers, and change in use did not influence naltrexone's effect on PHDD. CONCLUSIONS: These data confirm past findings that naltrexone is more efficacious in those who use nicotine/cigarettes. Compared to previous work on the OPRM1 A118G SNP, it appears that nicotine-use might be a more salient predictor of naltrexone treatment response. While naltrexone did not change cigarette use during the study, and smoking change was not related to alcohol reduction, it should be noted that participants were not seeking smoking cessation and MM did not address this issue.

Predictors of Naltrexone Response in a Randomized Trial: Reward-Related Brain Activation, OPRM1 Genotype, and Smoking Status.

This corrects the article DOI: 10.1038/npp.2017.74.

Predictors of Naltrexone Response in a Randomized Trial: Reward-Related Brain Activation, OPRM1 Genotype, and Smoking Status.

Naltrexone reduces drinking among individuals with alcohol use disorders (AUDs), but it is not effective for everyone. Variability in its effects on reward-related brain activation, genetic variation, and/or cigarette smoking may account for this mixed response profile. This randomized clinical trial tested the effects of naltrexone on drinking and alcohol cue-elicited brain activation, evaluated whether OPRM1 A118G genotype or smoking moderated these effects, and explored whether the effects of medication on cue-elicited activation predicted subsequent drinking. One hundred and fifty-two treatment-seeking individuals with alcohol dependence, half preselected to carry at least one A118G G (Asp) allele, were randomized to naltrexone (50 mg) or placebo for 16 weeks and administered an fMRI alcohol cue reactivity task at baseline and after 2 weeks of treatment. Naltrexone, relative to placebo, significantly reduced alcohol cue-elicited activation of the right ventral striatum (VS) between baseline and week 2 and reduced heavy drinking over 16 weeks. OPRM1 genotype did not significantly moderate these effects, but G-allele carriers who received naltrexone had an accelerated return to heavy drinking after medication was stopped. Smoking moderated the effects of medication on drinking, such that naltrexone was superior to placebo only among smokers. The degree of reduction in right VS activation between scans interacted with medication in predicting subsequent drinking, such that individuals with greater reduction in activation who received naltrexone, but not placebo, experienced the least heavy drinking during the following 14 weeks. These data replicate previous findings that naltrexone reduces heavy drinking and reward-related brain activation among treatment-seeking individuals with AUDs, and indicate that smoking and the magnitude of reduction in cue-elicited brain activation may predict treatment response.

Neurocognitive performance, alcohol withdrawal, and effects of a combination of flumazenil and gabapentin in alcohol dependence.

BACKGROUND: Among some alcohol-dependent individuals, early alcohol abstinence is marked by alcohol withdrawal (AW), a phenomenon mediated by GABA and glutamate signaling. We previously reported that a combination of 2 medications that affect GABA and glutamate tone, gabapentin and flumazenil, more effectively reduced drinking among individuals with higher pretreatment AW (Anton et al., 2009). This study evaluated whether this finding is related to changes in neurocognitive performance, which is also affected by cortical GABA and glutamate tone. METHODS: Neurocognitive performance was assessed at baseline and twice during the first week of treatment among 60 alcohol-dependent participants in the previously published clinical trial. RESULTS: AW was associated with poorer baseline performance on 4 of 8 measures, and individuals with higher baseline AW who received the gabapentin and flumazenil combination demonstrated greater improvement on a measure of response inhibition than those with lower AW or those who received a combination of placebos. Improvement in response inhibition during the first week and medication group interacted in their effect on subsequent drinking, such that improvement predicted greater abstinence only among individuals who received gabapentin and flumazenil. Improvement on other neurocognitive measures was neither differentially impacted by medication or baseline AW nor related to subsequent drinking. CONCLUSIONS: Taken together, these data suggest that acute AW accounts for a small proportion of variance in neurocognitive performance, that gabapentin and flumazenil slightly improve response inhibition during early abstinence, and that such improvement may somewhat reduce later drinking. However, these medications may not affect other neurocognitive domains.

Gabapentin combined with naltrexone for the treatment of alcohol dependence.

OBJECTIVE: Naltrexone, an efficacious medication for alcohol dependence, does not work for everyone. Symptoms such as insomnia and mood instability that are most evident during early abstinence might respond better to a different pharmacotherapy. Gabapentin may reduce these symptoms and help prevent early relapse. This clinical trial evaluated whether the combination of naltrexone and gabapentin was better than naltrexone alone and/or placebo during the early drinking cessation phase (first 6 weeks), and if so, whether this effect persisted. METHOD: A total of 150 alcohol-dependent individuals were randomly assigned to a 16-week course of naltrexone alone (50 mg/day [N=50]), naltrexone (50 mg/day) with gabapentin (up to 1,200 mg/day [N=50]) added for the first 6 weeks, or double placebo (N=50). All participants received medical management. RESULTS: During the first 6 weeks, the naltrexone-gabapentin group had a longer interval to heavy drinking than the naltrexone-alone group, which had an interval similar to that of the placebo group; had fewer heavy drinking days than the naltrexone-alone group, which in turn had more than the placebo group; and had fewer drinks per drinking day than the naltrexone-alone group and the placebo group. These differences faded over the remaining weeks of the study. Poor sleep was associated with more drinking in the naltrexone-alone group but not in the naltrexone-gabapentin group, while a history of alcohol withdrawal was associated with better response in the naltrexone-gabapentin group. CONCLUSIONS: The addition of gabapentin to naltrexone improved drinking outcomes over naltrexone alone during the first 6 weeks after cessation of drinking. This effect did not endure after gabapentin was discontinued.

Efficacy of a combination of flumazenil and gabapentin in the treatment of alcohol dependence: relationship to alcohol withdrawal symptoms.

Improved treatment of alcohol dependence is a high priority, including defining subtypes that might respond differently. We evaluated a medication combination of intravenous flumazenil (FMZ) and oral gabapentin (GBP) in alcoholics who did and did not exhibit pretreatment alcohol withdrawal (AW) symptoms. Sixty alcohol-dependent individuals (44 with low AW and 16 with high AW) were randomized to receive FMZ (2 mg of incremental bolus for 20 minutes for 2 consecutive days) and GBP (up to 1200 mg nightly for 39 days) or their inactive placebos. Alcohol withdrawal was measured for the first 2 days, and drinking, sleep parameters, and adverse events were monitored during weekly evaluations, along with behavioral counseling sessions. Percent days abstinent (PDA) during treatment and time to first heavy drinking (TFHD) day were primary outcome variables. There was an interaction between the pretreatment AW status and the medication group on PDA (P = 0.0006) and TFHD (P = 0.06). Those in the high AW group had more PDA and more TFHD if treated with active medications, whereas those in the low AW group had more PDA and more TFHD if treated with placebo. This interaction remained for those totally abstinent (P = 0.03) and was confirmed by percent carbohydrate-deficient transferrin values. In addition, the pattern of response remained up to 8 weeks after treatment. In addition, in those with high AW, greater improvement in AW symptoms was observed in the active medication group compared with the placebo group. These results suggest a differential response to FMZ/GBP treatment, depending on pretreatment AW status that should be taken into account during future treatment trials.

Blood pressure reduction during treatment for alcohol dependence: results from the Combining Medications and Behavioral Interventions for Alcoholism (COMBINE) study.

AIMS: Heavy drinking is associated with hypertension. This study evaluated blood pressure changes occurring during treatment for alcohol dependence. PARTICIPANTS: Subjects included 1383 people participating in the Combining Medications and Behavioral Interventions for Alcoholism (COMBINE) study, a large multi-center treatment study for alcohol dependence. MEASUREMENTS: Methods appropriate for repeated-measures data were used to assess the relationship of percentage of drinking days (PDD) to systolic and diastolic blood pressure over a 16-week treatment period. Modification of these associations by demographic and other variables was assessed. FINDINGS: Blood pressure reduction was evident only in people who were above the median blood pressure at baseline. In this group, systolic blood pressure decreased by an average of 12 mmHg and diastolic blood pressure decreased by an average of 8 mmHg. Blood pressure reduction occurred during the first month of treatment. This effect was similar regardless of age, sex, body mass index, reported history of hypertension and use of anti-hypertensive medications. An observed association between blood pressure and PDD in Caucasians was not evident in African Americans due largely to their lower pre-treatment blood pressure. CONCLUSIONS: Reduction in alcohol consumption has a potent anti-hypertensive effect in alcoholics with higher blood pressure. For hypertensive, alcohol-dependent people, treatment for alcoholism should be considered a major component of anti-hypertensive therapy.

What role does measuring medication compliance play in evaluating the efficacy of naltrexone?

BACKGROUND: Compliance with medication in pharmacotherapy trials of alcoholism has been shown to be equal to, or more, important than in other areas of medicine. Research has suggested that naltrexone's effectiveness can be greatly influenced by the compliance of participants in clinical trials. Presently, we compare 2 compliance measurement methods [urine riboflavin and medication event monitoring system (MEMS)] used simultaneously to evaluate naltrexone's efficacy and the impact of compliance on the size of observable treatment effects. METHODS: One hundred and thirty-seven of 160 randomized alcoholic patients completed 12-weeks (84 days) of naltrexone or placebo and cognitive behavioral therapy (CBT) or motivational enhancement therapy (MET). Urine riboflavin was determined during study weeks 2, 6, and 12. The MEMS provided a detailed computerized record of when a participant opened their medication bottle throughout the trial. Baseline predictors of MEMS (80% openings) and urine riboflavin (>or=1,500 ng/mL by fluorimetry) compliance were examined. The effects of the treatments in the compliant participants defined by one, the other, or both methods were compared and contrasted with a previously reported intent-to-treat analysis where compliance was not taken into account. RESULTS: Age was predictive of compliance. 105 participants were deemed compliant via urine riboflavin criteria, 87 via MEMS, and 77 when both criteria were met, with no significant differences between treatment groups. The most compliant participants showed a significant medication by therapy interaction. Those treated with naltrexone/CBT showed more abstinence days (p<0.03), less heavy drinking days (p<0.03) and less total drinks (p<0.03) than the other groups. The effect size of this interaction increased from about 0.2 in the intent-to-treat analysis, to about 0.4 to 0.5 in the compliant group analyses, with little difference between compliance measurement methods. CONCLUSIONS: Compliance measurement does appear to influence the evaluation of the efficacy of naltrexone within the context of CBT. Treatment effect sizes approximately doubled in the most compliant individuals. Measuring compliance by either of 2 distinct methods provides approximately similar results. As compliance with naltrexone within the context of CBT has such a large impact of treatment outcome, methods of enhancing compliance during treatment should be given the utmost attention.

Coordinating and monitoring multisite clinical trials that combine pharmacological and behavioral treatments.

OBJECTIVE: Coordination of a large, multicenter Phase 3 clinical trial is critical to the success of the trial. The focus of this article is to describe the special challenges involved in the coordination of the 11 clinical centers conducting the COMBINE clinical trial and to discuss the challenges of monitoring the information collected on the 1,383 participants enrolled in this trial. METHOD: The role of the coordinating center in working with the clinical sites is to ensure both high data quality and that the intervention protocol is conducted with appropriate attention paid to patient safety and consistency across sites. To satisfy those goals, a research committee of investigators and coordinating center staff was formed. The committee monitored adverse event reporting, participant safety, recruitment, delivery of the interventions, collection of assessments and completeness and timeliness of transfer of data to the coordinating center. Objective measures of performance were determined for each criterion to provide the principal investigators, study sponsor and Data and Safety Monitoring Board with feedback on conduct of the trial. Site performance as defined by these criteria was evaluated periodically, with both detailed written and verbal feedback provided to each investigator and study coordinator. RESULTS: The system was successful in detecting sites with performance issues, providing feedback to site personnel and measuring improvement. Study leadership, clinical center staff and coordinating center staff felt that the procedures for identifying and solving performance issues worked well and improved overall performance. CONCLUSIONS: Establishing an organizational structure that provided (1) leadership, (2) a venue for communication, (3) performance criteria and (4) a process for monitoring performance goals and providing feedback has enabled COMBINE to achieve success in reaching these markers of clinical trial practice.

Sertraline and cognitive behavioral therapy for depressed alcoholics: results of a placebo-controlled trial.

Alcoholism and depression are common disorders that frequently co-occur in the same individual. Selective serotonin reuptake inhibitors (SSRIs) are effective in the treatment of depression and also had decreased drinking in some studies of heavy drinkers and alcoholics. The reported effect of serotonergic medications on alcohol intake in depressed alcoholics has not been consistent. Most previous studies have not investigated the use of an SSRI in the context of cognitive behavioral therapy (CBT), a known efficacious treatment of both alcoholism and depression. The study presented here was a randomized placebo-controlled 12-week trial of sertraline combined with individual CBT focused on both alcoholism relapse prevention and depressive symptoms. Subjects were 82 currently depressed, actively drinking alcohol-dependent individuals. Subjects had either primary (independent) major depression (70 subjects) or substance-induced mood disorder and at least 1 first-degree relative (parent, sibling, or child) with an affective disorder (12 subjects). Depression and alcohol consumption outcomes were measured weekly over 12 weeks. Sertraline was well tolerated and all subjects had decreases in both depression and alcohol use during the study compared with baseline. Subjects who received sertraline had fewer drinks per drinking day than subjects who received placebo, but other drinking outcomes were not different between the 2 treatment groups. Treatment with sertraline was associated with less depression at the end of treatment in female subjects compared with female subjects who received placebo. Less drinking during the study was associated with improved depression outcome. The findings in this study suggest that sertraline, compared with placebo, may provide some modest benefit in terms of drinking outcome and also may lead to improved depression in female alcohol-dependent subjects. Additionally, alcohol relapse prevention CBT, delivered according to manual guidelines with modifications that provide specific attention to depression, appeared to be of benefit to subjects, although this interpretation is limited by the design of the study.