The placebo effect in clinical trials for alcohol dependence: an exploratory analysis of 51 naltrexone and acamprosate studies

Effects of a novel GABA-B positive allosteric modulator, ASP8062, on alcohol cue-elicited craving and naturalistic alcohol consumption in a multisite randomized, double-blind, placebo-controlled trial

BACKGROUND

The γ-aminobutyric acid-B (GABAB) receptor is a promising target for the development of new medications to treat alcohol use disorder (AUD). The GABAB agonist baclofen has been reported to reduce alcohol consumption but is associated with some undesirable side effects, including sedation. ASP8062 is a novel compound that acts as a positive allosteric modulator at the GABAB receptor and may be more tolerable than baclofen. This proof-of-concept human laboratory clinical trial evaluated the safety profile of ASP8062 and tested its effects on cue-elicited alcohol craving and alcohol use among treatment-seeking individuals with AUD.

METHODS

This double-blind, randomized, multisite trial tested the effect of ASP8062 (25 mg once daily), relative to placebo, on alcohol cue-elicited craving in a laboratory setting and alcohol consumption, craving, mood, sleep, cigarette smoking, and alcohol-related consequences in the natural environment over a 6-week treatment period. Participants were 60 individuals (26 females and 34 males) with moderate or severe AUD.

RESULTS

ASP8062, relative to placebo, was well tolerated, and there were no adverse events (AEs) that significantly differed between treatment groups. Most AEs were mild/moderate, and there were no serious AEs among individuals treated with ASP8062. However, ASP8062 did not attenuate alcohol cue-elicited craving compared with placebo. Moreover, exploratory analyses indicated that ASP8062, relative to placebo, did not significantly affect alcohol consumption, naturalistic alcohol craving, mood, sleep, cigarette smoking, or alcohol-related negative consequences during the 6-week treatment period.

CONCLUSIONS

Although ASP8062 was well tolerated with no serious AEs, the novel compound did not significantly dampen alcohol cue-elicited craving or improve other AUD-related outcome measures. These data indicate positive allosteric modulation of the GABAB receptor at the dose evaluated here may not blunt alcohol cue-elicited craving, and preliminary drinking outcome data suggest it may not be an efficacious treatment strategy for AUD.

Medication development for AUD: A systematic review of clinical trial methodology

Refining clinical trial methodology has become increasingly important as study design is shown to influence treatment efficacy. To maximize the efficiency of randomized clinical trials (RCTs), researchers aim to establish standardized practices. The goal of this systematic review is to describe methodological practices of clinical trials for alcohol use disorder (AUD) over the past 40 years. To achieve this goal, a PubMed search was conducted in April 2023 for RCTs on AUD medications published between July 2018 through April 2023. Resulting studies were combined with a previous search from 1985 through 2018. Inclusion criteria for the RCT studies were: (1) a randomized controlled trial, (2) double or single blinded, (3) placebo or active control condition, (4) alcohol use as the primary endpoint, (5) 4 or more weeks of treatment, and (6) 12 or more weeks of follow-up. In total, methodological data from 139 RCTs representing 19 medications and spanning the past four decades were summarized. Results indicated that the most common medications tested were naltrexone (k = 42), acamprosate (k = 24), and baclofen (k = 11). On average, participants were 74% male and consumed 226 drinks per month pre-randomization. The median length of treatment was 12 weeks (IQR = 12-16; min = 4 max = 52) and the median follow-up duration was 12.5 weeks (IQR: 12-26; min = 7 max = 104). There were two broad domains of outcomes (i.e., abstinence and heavy drinking), with most studies featuring outcomes from both domains (k = 87; 63%). Reporting practices were summarized by decade, revealing an increased enrollment of females, better reporting of race and ethnicity data, and less studies requiring pre-trial abstinence. This review summarizes the current state of the literature on randomized clinical trials for AUD including effect sizes for individual studies and summaries of key methodological features across this representative set of clinical trials.

Efficacy of medications for the treatment of alcohol use disorder (AUD): A systematic review and meta-analysis considering baseline AUD severity

Baseline severity of alcohol use disorder (AUD) is an influencing factor in the response to medications recommended for the treatment of AUD. The scarce efficacy of AUD medications partly justifies their limited uses. We were interested in evaluating the efficacy of approved and recommended AUD medications using generic inverse-variance, an analysis facilitating comparison between medications and placebo both at the end of the study and, concomitantly, to baseline values for the same participants. We conducted a systematic review to include randomized controlled trials (RCTs) comparing any medication to placebo providing, both at baseline and end of treatment, percent heavy drinking days (%HDD), percent drinking days (%DD), and/or drinks per drinking day (DDD). We searched PubMed, Embase, PMC, and three CT registers from inception to April 2023. A total of 79 RCTs (11,737 AUD participants; 30 different medications) were included: 47 RCTs (8465 participants) used AUD medications, and 32 RCTs (3272 participants) used other medications. At baseline, participants consumed on average approximately 12 DDD, and experienced 70 % DD, and 61 % HDD. Placebo halved or reduced these values to a third. Compared to placebo, AUD medications further reduced these outcomes (moderate to high certainty evidence). Other medications reduced the DDD without modifying other alcohol outcomes. AUD medications increased the risk of developing adverse events (high-certainty evidence). Despite the large placebo effects, our results support the benefits of providing AUD medications to people with AUD, helping them reduce alcohol consumption.

Sodium oxybate: A comprehensive review of efficacy and safety in the treatment of alcohol withdrawal syndrome and alcohol dependence

Alcohol dependence (AD) significantly impacts public health, affecting 3.4% of people aged 18-64 and contributing to around 12% of overall mortality. Individuals with AD have a markedly reduced life expectancy, dying up to 28 years earlier than the general population. Current treatments for AD show limited efficacy, with many patients not responding to these interventions, highlighting the need for new therapeutic options with novel mechanisms of action. Sodium oxybate (SMO), the sodium salt of GHB, is one such candidate, pharmacologically similar to alcohol; it acts on several neurotransmitters including GABA, potentially mitigating withdrawal symptoms and craving for alcohol. SMO has been clinically used in Italy and Austria since the 1990s, approved for treating alcohol withdrawal syndrome (AWS) and for maintaining abstinence in AD patients. Several randomized clinical trials (RCTs) and meta-analyses showed evidence of SMO to be effective and safe in these indications. For AWS, SMO was more effective than placebo and as effective as benzodiazepines in reducing withdrawal symptoms. For maintaining abstinence, SMO significantly improved continuous abstinence duration and abstinence rate compared to placebo. Comprehensive clinical data indicate that SMO is well-tolerated, with main adverse effects being mild, such as dizziness and vertigo, and serious adverse events being rare. The effectiveness and safety of SMO, coupled with its approval in two EU countries affirm its potential as a treatment option for AD, particularly in severe cases. Further RCTs, especially with stratification by severity of dependence, are suggested to refine our understanding of its efficacy across different patient subgroups.

Low-dose ondansetron: A candidate prospective precision medicine to treat alcohol use disorder endophenotypes

BACKGROUND

Alcohol use disorder (AUD) is among the leading causes of morbidity and mortality worldwide, and over 95 million people live with alcohol dependence globally. The estimated heritability of AUD is 50-60 %, and multiple genes are thought to contribute to various endophenotypes of the disease. Previous clinical trials support a precision medicine approach using ondansetron (AD04, a 5-HT3 antagonist) by segregating AUD populations by the bio-genetic endophenotype of specific serotonergic genotypes and the bio-psychosocial endophenotype of the severity of drinking or both. By targeting the modulation of biogenetic signaling within the biopsychosocial context of AUD, low-dose AD04 holds promise in reducing alcohol consumption among affected individuals while minimizing adverse effects.

METHODS

This was a phase III, 6-month, 25-site, randomized, placebo-controlled clinical trial using AD04 to treat DSM-V-categorized AUD individuals who were pre-stratified into the endophenotypes of heavy or very heavy drinking individuals and possessed a pre-defined profile of genetic variants related to the serotonin transporter and serotonin-3AB receptor. Participants (N = 303) presented moderate to severe AUD, >80 % were men, mostly in their fifties, and >95 % were of European descent. Low-dose AD04 (approx. 033 mg twice daily) or a matching placebo was administered twice daily for 6 months. Brief Behavioral Compliance Enhancement Treatment (BBCET [53]) was administered every two weeks to enhance medication compliance and clinic attendance.

RESULTS

There was a significant reduction in the monthly percentage of heavy drinking days, PHDD (-46·7 % (2·7 %), 95 %CI: -52·1 % to -41·2 % vs. -38·1 % (2·9 %), 95 %CI: -43·8 % to -32·5 %, respectively; LS mean difference=-8·5 %; p = 0.03) among AD04-treated vs. placebo-receiving heavy drinking individuals at month 6. Heavy drinking individuals were also less likely to be diagnosed with AUD [Month 1: -32·0 % (2·8 %), 95 %CI: -37·5 % to -26·5 % vs. -23·2 % (2·9 %), 95 %CI: -28·9 to -17·5 %; LS mean difference= -8·8 %; p = 0·026)], and improved on the WHO quality of life BREF scale with a significant effect for at least a 1-level downward shift (OR = 3.4; 95 % CI: 1·03-11·45, p = 0·044). Importantly, heavy drinking individuals, as distinct from very heavy drinking individuals, were the bio-psychosocial endophenotype more predictive of therapeutic response to AD04. AD04 had an exceptional safety and tolerability profile, like the placebo's.

CONCLUSIONS

In this Phase 3 clinical trial, AD04 was shown to be a promising treatment for currently drinking heavy drinking individuals with AUD who also possess a specific genotypic profile in the serotonin transporter and serotonin-3AB receptor complex. Using AD04 to reduce the harm of AUD in heavy drinking individuals who are currently drinking, without the necessity of abstinence or detoxification from alcohol use, is an important advance in the field of precision medicine. AD04's adverse events profile, which was like placebo, should enhance accessibility and acceptance of modern medical treatment for AUD by lowering the incorrect but commonly perceived stigma of personal failure.

Prazosin and cyproheptadine in combination in the treatment of alcohol use disorder: A randomized, double-blind, placebo-controlled trial

BACKGROUND AND AIMS

Pre-clinical studies suggest that the simultaneous blockade of the α1b and 5HT2A receptors may be effective in reducing alcohol consumption. This study aimed to assess the efficacy and safety of prazosin (α1b blocker) and cyproheptadine (5HT2A blocker) combination in decreasing total alcohol consumption (TAC) in alcohol use disorder (AUD).

DESIGN, SETTING AND PARTICIPANTS

This was a double-blind, parallel group, placebo-controlled, Phase 2, randomized clinical trial conducted in 32 addiction treatment centres in France. A total of 108 men and 46 women with severe AUD took part.

INTERVENTION

Participants were randomly assigned to one of the following 3-month treatments: (1) low-dose group (LDG) receiving 8 mg cyproheptadine and 5 mg prazosin extended-release (ER) formulation daily; (2) high-dose group (HDG) receiving 12 mg cyproheptadine and 10 mg prazosin ER daily; and (3) placebo group (PG) receiving placebo of cyproheptadine and prazosin ER. A total of 154 patients were randomized: 54 in the PG, 54 in the LDG and 46 in the HDG.

MEASUREMENTS

The primary outcome was TAC change from baseline to month 3.

FINDINGS

A significant main treatment effect in the change in TAC was found in the intent-to-treat population (P = 0.039). The HDG and LDG showed a benefit in the change in TAC from baseline to month 3 compared with PG: -23.6 g/day, P = 0.016, Cohen's d = -0.44; -18.4 g/day, P = 0.048 (Bonferroni correction P < 0.025), Cohen's d = -0.36. In a subgroup of very high-risk drinking-level participants (> 100 g/day of pure alcohol for men and > 60 g/day for women), the difference between the HDG and the PG in the primary outcome was -29.8 g/day (P = 0.031, Cohen's d = -0.51). The high and low doses were well-tolerated with a similar safety profile.

CONCLUSIONS

A randomized controlled trial of treatment of severe alcohol use disorder with a cyproheptadine-prazosin combination for 3 months reduced drinking by more than 23 g per day compared with placebo. A higher dose combination was associated with a larger magnitude of drinking reduction than a lower dose combination while showing similar safety profile.

Psychosocial and medication interventions to stop or reduce alcohol consumption during pregnancy

BACKGROUND

Despite the known harms, alcohol consumption is common in pregnancy. Rates vary between countries, and are estimated to be 10% globally, with up to 25% in Europe.

OBJECTIVES

To assess the efficacy of psychosocial interventions and medications to reduce or stop alcohol consumption during pregnancy.

SEARCH METHODS

We searched the Cochrane Drugs and Alcohol Group Specialised Register (via CRSLive), Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL, Web of Science, and PsycINFO, from inception to 8 January 2024. We also searched for ongoing and unpublished studies via ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). All searches included non-English language literature. We handsearched references of topic-related systematic reviews and included studies.

SELECTION CRITERIA

We included randomised controlled trials that compared medications or psychosocial interventions, or both, to placebo, no intervention, usual care, or other medications or psychosocial interventions used to reduce or stop alcohol use during pregnancy. Our primary outcomes of interest were abstinence from alcohol, reduction in alcohol consumption, retention in treatment, and women with any adverse event.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures.

MAIN RESULTS

We included eight studies (1369 participants) in which pregnant women received an intervention to stop or reduce alcohol use during pregnancy. In one study, almost half of participants had a current diagnosis of alcohol use disorder (AUD); in another study, 40% of participants had a lifetime diagnosis of AUD. Six studies took place in the USA, one in Spain, and one in the Netherlands. All included studies evaluated the efficacy of psychosocial interventions; we did not find any study that evaluated the efficacy of medications for the treatment of AUD during pregnancy. Psychosocial interventions were mainly brief interventions ranging from a single session of 10 to 60 minutes to five sessions of 10 minutes each. Pregnant women received the psychosocial intervention approximately at the end of the first trimester of pregnancy, and the outcome of alcohol use was reassessed 8 to 24 weeks after the psychosocial intervention. Women in the control group received treatment as usual (TAU) or similar treatments such as comprehensive assessment of alcohol use and advice to stop drinking during pregnancy. Globally, we found that, compared to TAU, psychosocial interventions may increase the rate of continuously abstinent participants (risk ratio (RR) 1.34, 95% confidence interval (CI) 1.14 to 1.57; I2 =0%; 3 studies; 378 women; low certainty evidence). Psychosocial interventions may have little to no effect on the number of drinks per day, but the evidence is very uncertain (mean difference -0.42, 95% CI -1.13 to 0.28; I2 = 86%; 2 studies; 157 women; very low certainty evidence). Psychosocial interventions probably have little to no effect on the number of women who completed treatment (RR 0.98, 95% CI 0.94 to 1.02; I2 = 0%; 7 studies; 1283 women; moderate certainty evidence). None of the included studies assessed adverse events of treatments. We downgraded the certainty of the evidence due to risk of bias and imprecision of the estimates.

AUTHORS' CONCLUSIONS

Brief psychosocial interventions may increase the rate of continuous abstinence among pregnant women who report alcohol use during pregnancy. Further studies should be conducted to investigate the efficacy and safety of psychosocial interventions and other treatments (e.g. medications) for women with AUD. These studies should provide detailed information on alcohol use before and during pregnancy using consistent measures such as the number of drinks per drinking day. When heterogeneous populations are recruited, more detailed information on alcohol use during pregnancy should be provided to allow future systematic reviews to be conducted. Other important information that would enhance the usefulness of these studies would be the presence of other comorbid conditions such as anxiety, mood disorders, and the use of other psychoactive substances.

Effects of dulaglutide on alcohol consumption during smoking cessation

BACKGROUNDAlcohol use disorder has a detrimental impact on global health and new treatment targets are needed. Preclinical studies show attenuating effects of glucagon-like peptide-1 (GLP-1) agonists on addiction-related behaviors in rodents and nonhuman primates. Some trials have shown an effect of GLP-1 agonism on reward processes in humans; however, results from clinical studies remain inconclusive.METHODSThis is a predefined secondary analysis of a double-blind, randomized, placebo-controlled trial evaluating the GLP-1 agonist dulaglutide as a therapy for smoking cessation. The main objective was to assess differences in alcohol consumption after 12 weeks of treatment with dulaglutide compared to placebo. The effect of dulaglutide on alcohol consumption was analyzed using a multivariable generalized linear model.RESULTSIn the primary analysis, participants out of the cohort (n = 255) who reported drinking alcohol at baseline and who completed 12 weeks of treatment (n = 151; placebo n = 75, dulaglutide n = 76) were included. The median age was 42 (IQR 33-53) with 61% (n = 92) females. At week 12, participants receiving dulaglutide drank 29% less (relative effect = 0.71, 95% CI 0.52-0.97, P = 0.04) than participants receiving placebo. Changes in alcohol consumption were not correlated with smoking status at week 12.CONCLUSIONThese results provide evidence that dulaglutide reduces alcohol intake in humans and contribute to the growing body of literature promoting the use of GLP-1 agonists in treatment of substance use disorders.TRIAL REGISTRATIONClinicalTrials.gov NCT03204396.FUNDINGSwiss National Foundation, Gottfried Julia Bangerter-Rhyner Foundation, Goldschmidt-Jacobson Foundation, Hemmi Foundation, University of Basel, University Hospital Basel, Swiss Academy of Medical Science.

Comorbid alcohol use disorder and posttraumatic stress disorder: A proof-of-concept randomized placebo-controlled trial of buprenorphine and naltrexone combination treatment

BACKGROUND

Effective pharmacologic treatments for comorbid alcohol use disorder (AUD) and posttraumatic stress disorder (PTSD) are lacking. Kappa (κ) opioid receptor antagonists may address this unmet need. Buprenorphine is a κ-opioid antagonist and a partial agonist of mu (μ) opioid receptors. Whereas naltrexone blocks all μ-mediated effects combining it with buprenorphine yields a pharmacologic net effect of opioid receptor antagonism. Because no κ-opioid receptor antagonist it available for clinical use, we tested this combination in a proof-of-concept study.

METHODS

Consenting participants were enrolled in a Phase II, multisite, double-blind, randomized, placebo-controlled trial evaluating the effectiveness of sublingual (SL) buprenorphine combined with extended-release (XR) injectable naltrexone for the treatment of comorbid AUD and PTSD. Eligible participants (n = 75) were randomized (1:1:1) to receive either buprenorphine 2 mg/day plus naltrexone-XR (n = 35), buprenorphine 8 mg/day plus naltrexone-XR (n = 6) or SL plus injectable placebo (n = 34) for 12 weeks. The buprenorphine 8 mg/day plus naltrexone-XR arm was dropped early in the trial due to the negative impact of COVID-19 on enrollment. A binary primary outcome of response at week 8 was defined as a decrease from baseline of ≥10 points on the past week Clinician-Administered PTSD Scale (CAPS-5) and a reduction of ≥1 of past month alcohol risk level, as defined by the World Health Organization (WHO) and measured by the Timeline Follow-Back.

RESULTS

Based on the results of a futility analysis, enrollment was stopped prior to reaching the initial goal of 90 participants. At the week eight primary timepoint, there were no statistically significant differences between buprenorphine plus naltrexone-XR and placebo group for the primary composite outcome (OR = 0.63; p-value = 0.52), or the subcomponents of the PTSD outcome (OR = 0.76; p-value = 0.69) and AUD outcome (OR = 0.17; p-value = 0.08). The placebo arm had a significantly higher proportion of participants with ≥1 WHO risk level reduction than the buprenorphine plus naltrexone-XR arm (OR = 0.18, p value = 0.02).

CONCLUSIONS

This is the first study to evaluate the potential of κ-opioid receptor antagonism for the treatment of comorbid AUD and PTSD. The combination of buprenorphine and naltrexone-XR showed no significant improvement over placebo for the composite, PTSD, or alcohol measures.

Sodium Oxybate for Alcohol Dependence: A Network Meta-Regression Analysis Considering Population Severity at Baseline and Treatment Duration

AIMS

The estimated effect of sodium oxybate (SMO) in the treatment of alcohol dependence is heterogeneous. Population severity and treatment duration have been identified as potential effect modifiers. Population severity distinguishes heavy drinking patients with <14 days of abstinence before treatment initiation (high-severity population) from other patients (mild-severity population). Treatment duration reflects the planned treatment duration. This study aimed to systematically investigate the effect of these potential effect moderators on SMO efficacy in alcohol-dependent patients.

METHODS

Network meta-regression allows for testing potential effect modifiers. It was selected to investigate the effect of the above factors on SMO efficacy defined as continuous abstinence (abstinence rate) and the percentage of days abstinent (PDA). Randomized controlled trials for alcohol dependence with at least one SMO group conducted in high-severity and mild-severity populations were assigned to a high-severity and mild-severity group of studies, respectively.

RESULTS

Eight studies (1082 patients) were retained: four in the high-severity group and four in the mild-severity group. The high-severity group was associated with larger SMO effect sizes than the mild-severity group: abstinence rate risk ratio (RR) 3.16, P = 0.004; PDA +26.9%, P < 0.001. For PDA, longer treatment duration was associated with larger SMO effect size: +11.3% per extra month, P < 0.001. In the high-severity group, SMO showed benefit: abstinence rate RR 2.91, P = 0.03; PDA +16.9%, P < 0.001. In the mild-severity group, SMO showed benefit only in PDA for longer treatment duration: +23.9%, P < 0.001.

CONCLUSIONS

In the retained studies with alcohol-dependent patients, high-severity population and longer treatment duration were associated with larger SMO effect sizes.

Sodium oxybate for the maintenance of abstinence in alcohol-dependent patients: An international, multicenter, randomized, double-blind, placebo-controlled trial

BACKGROUND

Sodium oxybate (SMO) has been shown to be effective in the maintenance of abstinence (MoA) in alcohol-dependent patients in a series of small randomized controlled trials (RCTs). These results needed to be confirmed by a large trial investigating the treatment effect and its sustainability after medication discontinuation.

AIMS

To confirm the SMO effect on (sustained) MoA in detoxified alcohol-dependent patients.

METHODS

Large double-blind, randomized, placebo-controlled trial in detoxified adult alcohol-dependent outpatients (80% men) from 11 sites in four European countries. Patients were randomized to 6 months SMO (3.3-3.9 g/day) or placebo followed by a 6-month medication-free period. Primary outcome was the cumulative abstinence duration (CAD) during the 6-month treatment period defined as the number of days with no alcohol use. Secondary outcomes included CAD during the 12-month study period.

RESULTS

Of the 314 alcohol-dependent patients randomized, 154 received SMO and 160 received placebo. Based on the pre-specified fixed-effect two-way analysis of variance including the treatment-by-site interaction, SMO showed efficacy in CAD during the 6-month treatment period: mean difference +43.1 days, 95% confidence interval (17.6-68.5; p = 0.001). Since significant heterogeneity of effect across sites and unequal sample sizes among sites (n = 3-66) were identified, a site-level random meta-analysis was performed with results supporting the pre-specified analysis: mean difference +32.4 days, p = 0.014. The SMO effect was sustained during the medication-free follow-up period. SMO was well-tolerated.

CONCLUSIONS

Results of this large RCT in alcohol-dependent patients demonstrated a significant and clinically relevant sustained effect of SMO on CAD.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04648423.

Repetitive Transcranial Magnetic Stimulation in Alcohol Dependence: A Randomized, Double-Blind, Sham-Controlled Proof-of-Concept Trial Targeting the Medial Prefrontal and Anterior Cingulate Cortices

BACKGROUND

Alcohol addiction is associated with a high disease burden, and treatment options are limited. In a proof-of-concept study, we used deep repetitive transcranial magnetic stimulation (dTMS) to target circuitry associated with the pathophysiology of alcohol addiction. We evaluated clinical outcomes and explored associated neural signatures using functional magnetic resonance imaging.

METHODS

This was a double-blind, randomized, sham-controlled trial. A total of 51 recently abstinent treatment-seeking patients with alcohol use disorder (moderate to severe) were randomized to sham or active dTMS, using an H7 coil targeting midline frontocortical areas, including the medial prefrontal and anterior cingulate cortices. Treatment included 15 sessions over 3 weeks, followed by five sessions over 3 months of follow-up. Each session delivered 100 trains of 30 pulses at 10 Hz. The primary predefined outcome was reduction in percentage of heavy drinking days, obtained using timeline follow-back interviews. Secondary analyses included self-reports of craving, ethyl glucuronide in urine, and brain imaging measures.

RESULTS

Both craving after treatment and percentage of heavy drinking days during follow-up were significantly lower in the active versus sham control group (percentage of heavy drinking days = 2.9 ± 0.8% vs. 10.6 ± 1.9%, p = .037). Active dTMS was associated with decreased resting-state functional connectivity of the dorsal anterior cingulate cortex with the caudate nucleus and decreased connectivity of the medial prefrontal cortex to the subgenual anterior cingulate cortex.

CONCLUSIONS

We provide initial proof-of-concept for dTMS targeting midline frontocortical structures as a treatment for alcohol addiction. These data strongly support a rationale for a full-scale confirmatory multicenter trial. Therapeutic benefits of dTMS appear to be associated with persistent changes in brain network activity.

Repetitive transcranial magnetic stimulation in treatment-seeking subjects with cocaine use disorder: A randomized, double-blind, sham-controlled trial

BACKGROUND

Cocaine use disorder (CUD) is a chronic and relapsing brain disorder with no approved treatments. Repetitive transcranial magnetic stimulation (rTMS) has shown promising results in open label and single-blind studies, reducing cocaine craving and consumption. Although, large randomized, double-blind, controlled trials are still missing.

OBJECTIVE

This multi-center, randomized, double-blind, sham-controlled study was designed to evaluate the safety and efficacy of multiple sessions of active rTMS compared to sham stimulation in patients with CUD.

METHODS

rTMS (15 Hz, 2 daily sessions for 5 days/week,for a total of 20 stimulation sessions) was delivered over the left DLPFC for two weeks of continuous treatment followed by 12 weeks of maintenance (1 day/week, twice a day), in a double-blind, randomized sham-controlled design. Our primary outcomes included self-reported cue-induced craving and cocaine consumption, as measured by percentage of negative urine tests. Our secondary outcomes included: 1) changes in depressive symptoms; 2) changes in cocaine withdrawal symptoms; and 3) changes in self-reported days of cocaine use.

RESULTS

Forty-two outpatients with CUD were enrolled in the active rTMS group and 38 patients in the sham group. We observed a significant decrease in self-reported cue-induced cocaine craving and consumption in both the active rTMS and sham, whereas no main effect of treatment was found. However, the active rTMS group showed greater changes in depressive symptoms. The improvement on depressive symptomatology was particularly marked among patients receiving a total number of rTMS sessions greater than 40 and those reporting more severe depressive symptoms at baseline.

CONCLUSIONS

A significant improvement of CUD symptoms during active rTMS treatment was observed. However, we did not observe significant differences in cocaine craving and consumption between treatment groups, highlighting the complexity of factors contributing to CUD maintenance. A significant improvement in depressive symptoms was observed in favour of the active group. Clinical trial registration details:clinicaltrials.govidentifierNCT03333460.

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.

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.

Intranasal oxytocin versus placebo for hyperphagia and repetitive behaviors in children with Prader-Willi Syndrome: A randomized controlled pilot trial

OBJECTIVE

The effects of intranasal oxytocin and placebo on hyperphagia and repetitive behaviors were compared in children and adolescents with Prader Willi Syndrome (PWS).

METHODS

Children and adolescents with PWS were enrolled in an 8-week double-blind placebo-controlled intranasal oxytocin randomized trial. Twenty-three (23) subjects were assigned to oxytocin (N = 11) or placebo (N = 12). Hyperphagia was measured with the Hyperphagia Questionnaire (HQ), and repetitive behavior was measured with Repetitive Behavior Scale- Revised (RBS-R).

RESULTS

There were modest significant treatment by-time interactions indicating reduction in hyperphagia and repetitive behaviors across time for placebo but no reduction for oxytocin. Total HQ score showed a greater average reduction of 1.81 points/week for the placebo group vs. oxytocin, with maximum reduction at week 4. There were also greater reductions on HQ-Drive and HQ-Behavior subscales on placebo vs. oxytocin. RBS-R subscales followed similar patterns to the HQ, with a significantly greater reduction in sameness subscale behaviors (average 0.825 points/week) in the placebo group compared to the oxytocin group. Oxytocin was well tolerated, and the only adverse event that was both more common and possibly related to oxytocin vs. placebo was nocturia (n = 1 vs 0).

CONCLUSION

Placebo was associated with modest improvement in hyperphagia and repetitive behaviors in childhood PWS whereas intranasal oxytocin was not associated with improvement in these domains. More work is needed to understand the meaning and mechanism of these findings on hyperphagia and repetitive behaviors in PWS.

Evidence-Based Pharmacotherapies for Alcohol Use Disorder: Clinical Pearls

Pathologic alcohol use affects more than 2 billion people and accounts for nearly 6% of all deaths worldwide. There are three medications approved for the treatment of alcohol use disorder by the US Food and Drug Administration (FDA): disulfiram, naltrexone (oral and long-acting injectable), and acamprosate. Of growing interest is the use of anticonvulsants for the treatment of alcohol use disorder, although currently none are FDA approved for this indication. Baclofen, a γ-aminobutyric acid B receptor agonist used for spasticity and pain, received temporary approval for alcohol use disorder in France. Despite effective pharmacotherapies, less than 9% of patients who undergo any form of alcohol use disorder treatment receive pharmacotherapies. Current evidence does not support the use of pharmacogenetic testing for treatment individualization. The objective of this review is to provide knowledge on practice parameters for evidenced-based pharmacologic treatment approaches in patients with alcohol use disorder.

Study Characteristics Influence the Efficacy of Substance Abuse Treatments: A Meta-analysis of Medications for Smoking Cessation

BACKGROUND

Understanding study characteristics' influence on treatment efficacy could improve interpretation of trials' outcomes. We examined study characteristics as predictors of outcomes in clinical trials of medications for tobacco use.

METHODS

We obtained and analyzed data on 44 trials of nicotine gum, 37 trials of nicotine patch, 27 trials of varenicline, and 43 trials of bupropion from Cochrane reviews. We extracted and analyzed data for 15 study characteristics, odds ratios (ORs), and percent abstinent in control and medication conditions. We used general linear models to determine which study characteristics explained the variability among outcomes after controlling for medication characteristics.

RESULTS

Study characteristics accounted for 12% of the variance in odds ratios among patch trials, 16% among gum trials, 16% among varenicline trials, and 34% among bupropion trials above and beyond medication characteristics. Patch and gum trials with industry funding had larger odds ratios than those without. Among patch trials, this appeared to be due to less abstinence in industry-funded trials' control conditions. Bupropion trials published earlier had larger odds ratios, which appeared to be due to less abstinence in control conditions. The reason for study characteristics' influence on varenicline trials was unclear.

DISCUSSION

Study characteristics influenced the assessment of treatment efficacy above and beyond medication characteristics in smoking cessation trials. Our findings that study characteristics are associated with higher or lower efficacy does not suggest that the effect size under one versus another condition is the more valid outcome. Future studies are needed to determine which study characteristics reliably influence efficacy because this would help investigators and clinicians interpret trials.

IMPLICATIONS

Study characteristics influenced the estimates of treatment efficacy but individual characteristics' influence on efficacy appeared to differ among different medications for smoking cessation. We encourage researchers to report study characteristics to improve interpretation of findings and systematic reviews, and to account for nontreatment-related variables to better estimate the efficacy of treatments.

Placebo effects and the molecular biological components involved

Pharmacologically inactive substances have been used in medicine for more than 700 years and can trigger beneficial responses in the human body, which is referred to as the placebo effects or placebo responses. This effect is robust enough to influence psychosocial and physiological responses to the placebo and to active treatments in many settings, which has led to increased interest from researchers. In this article, we summarise the history of placebo, the characteristics of placebo effects and recent advancements reported from the studies on placebo effects and highlight placebome studies to identify various molecular biological components associated with placebo effects. Although placebos have a long history, the placebome concept is still in its infancy. Although behavioural, neurobiological and genetic studies have identified that molecules in the dopamine, opioid, serotonin and endocannabinoid systems might be targets of the placebo effect, placebome studies with a no-treatment control (NTC) are necessary to identify whole-genome genetic targets. Although bioinformatics analysis has identified the molecular placebome module, placebome studies with NTCs are also required to validate the related findings.

Advances in the science and treatment of alcohol use disorder

Alcohol is a major contributor to global disease and a leading cause of preventable death, causing approximately 88,000 deaths annually in the United States alone. Alcohol use disorder is one of the most common psychiatric disorders, with nearly one-third of U.S. adults experiencing alcohol use disorder at some point during their lives. Alcohol use disorder also has economic consequences, costing the United States at least $249 billion annually. Current pharmaceutical and behavioral treatments may assist patients in reducing alcohol use or facilitating alcohol abstinence. Although recent research has expanded understanding of alcohol use disorder, more research is needed to identify the neurobiological, genetic and epigenetic, psychological, social, and environmental factors most critical in the etiology and treatment of this disease. Implementation of this knowledge in clinical practice and training of health care providers is also needed to ensure appropriate diagnosis and treatment of individuals suffering from alcohol use disorder.

Reduction in Drinking was Associated With Improved Clinical Outcomes in Women With HIV Infection and Unhealthy Alcohol Use: Results From a Randomized Clinical Trial of Oral Naltrexone Versus Placebo

BACKGROUND

Alcohol consumption is associated with poor health outcomes in women living with HIV (WLWH), but whether medication can help to reduce drinking in non-treatment-seeking women or whether reduction in drinking improves HIV outcomes is unclear. We conducted a randomized clinical trial (RCT) of daily oral naltrexone (50 mg) versus placebo in WLWH who met criteria for current unhealthy alcohol use.

METHODS

WLWH with current unhealthy alcohol use (>7 drinks/wk or >3 drinks/occasion) were randomly assigned to daily oral naltrexone 50 mg (n = 96) or placebo (n = 98) for 4 months. Drinking outcomes, including the proportion of women who reduced (

RESULTS

The participants' mean age was 48 years, 86% were African American, and 94% were receiving HIV antiretroviral therapy. Among all participants, 89% and 85% completed the 4-month and 7-month follow-ups, respectively. Participants in both groups substantially reduced drinking over time. At 1 and 3 months, naltrexone was associated with a greater reduction in drinking (p < 0.05), but the proportion who reduced/quit drinking at 4 months (52% vs. 45%, p = 0.36) or 7 months (64% in both groups) was not different. HIV viral suppression at follow-up was significantly better in participants who reduced/quit drinking versus those continuing unhealthy alcohol use at 4 months (72% vs. 53%, p = 0.02) and 7 months (74% vs. 54%, p = 0.02).

CONCLUSIONS

Participating in an RCT to reduce drinking was associated with significant drinking reduction regardless of medication assignment, suggesting that nonmedication aspects of research study participation (e.g., repeated assessments and support from research staff) could be important interventions to help reduce drinking outside of research studies. Drinking reduction was associated with improved HIV viral suppression, providing evidence to support recommendations to avoid unhealthy alcohol use among WLWH.

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Key Words

• Alcohol Consumption
• HIV Infection
• Pharmacotherapy
• Randomized Clinical Trial
• Women

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MESH Headings

• Alcohol Deterrents/therapeutic use
• Alcohol Drinking/drug therapy
• Alcohol-Related Disorders/complications
• Alcohol-Related Disorders/drug therapy
• Anti-Retroviral Agents/therapeutic use
• CD4 Lymphocyte Count/statistics & numerical data
• Female
• HIV Infections/complications
• HIV Infections/drug therapy
• Humans
• Middle Aged
• Naltrexone/therapeutic use
• Treatment Outcome
• Viral Load/statistics & numerical data

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Grants

• U24 AA022002 NIAAA NIH HHS
• U01 AA020797 NIAAA NIH HHS
• U24 AA022003 NIAAA NIH HHS
• UL1 TR000460 NCATS NIH HHS
• P01 AA029543 NIAAA NIH HHS

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Affiliation(s)

Robert L. Cook Department of Epidemiology, (RLC, ZZ), University of Florida, Gainesville
Zhi Zhou Department of Epidemiology, (RLC, ZZ), University of Florida, Gainesville
Maria Jose Miguez Florida, School of Integrated Science and Humanity, (MJM, CQ), Florida International University, Miami, Florida
Clery Quiros Florida, School of Integrated Science and Humanity, (MJM, CQ), Florida International University, Miami, Florida
Luis Espinoza Public Health & Medical Affairs, (LE), Gilead Sciences Inc., Miami, Florida
John E. Lewis Psychiatry & Behavioral Sciences, (JEL), University of Miami School of Medicine, Miami, Florida
Babette Brumback Biostatistics, (BB), University of Florida, Gainesville, Florida
Kendall Bryant Alcohol and HIV/AIDS Research, (KB), National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland

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Outcome Assessment in Trials of Pharmacological Treatments for Alcohol Use Disorders: Fair and Strict Testing

Outcome assessment in the pharmacological treatment of alcohol use disorders (AUDs) faces specific challenges resulting from low adherence to treatment, high rates of dropout, and the susceptibility of patient self-reports to bias. This review discusses methodological issues in planning, conducting, and interpreting clinical trials on AUD treatment against the background of the principle of 'strictness and fairness' of testing. Threats to fairness include factors that limit the implementation of an intervention, such as low compliance and early treatment termination. In turn, fairness of testing is increased by factors that support the degree to which an intervention is implemented, such as the use of adequate pretreatments and the matching of psychosocial and pharmacological treatment strategies. Furthermore, selecting outcomes on the basis of an intervention's mechanism of action and including continuous outcomes as sensitive measures of drinking change further increases fairness by increasing the likelihood that the data will adequately reflect the effects of the intervention. On the other hand, strictness of testing is increased by all measures that limit the influence of confounders that could potentially lead to an overestimation of effects. The use of a side effect-mimicking placebo to prevent an unmasking of blinding and the repeated assessment of alcohol biomarkers to validate drinking self-reports might be valid strategies to further increase the strictness of testing by limiting risks of bias in trials of AUD treatment.

Consumption outcomes in clinical trials of alcohol use disorder treatment: Consideration of standard drink misestimation

Background. The Food and Drug Administration recently added a new clinical endpoint for evaluating the efficacy of alcohol use disorder (AUD) treatment that is more inclusive of treatment goals besides abstinence: no heavy drinking days (NHDD). However, numerous critiques have been noted for such binary models of treatment outcome. Further, there is mounting evidence that participants inaccurately estimate the quantities of alcohol they consume during drinking episodes (i.e., drink size misestimation), which may be particularly problematic when using a binary criterion (NHDD) compared to a similar, continuous alternative outcome variable: percent heavy drinking days (PHDD). Yet, the impact of drinking misestimation on binary (e.g., NHDD) versus continuous outcome variables (e.g., PHDD) has not been studied. Objectives. Using simulation methods, the present study examined the potential impact of drink size misestimation on NHDD and PHDD. Methods. Data simulations were based on previously published findings of the amount of error in how much alcohol is actually poured when estimating standard drinks. We started with self-reported daily drinking data from COMBINE study participants with complete data (N = 888; 68.1% male), then simulated inaccuracy in those estimations based on literature on standard drink size misestimation. Results. Clinical trial effect sizes were consistently lower for NHDD than for PHDD. Drink size misestimation further lowered effect sizes for NHDD and PHDD. Conclusions. Drink size misestimation may lead to inaccurate conclusions about drinking outcomes and the comparative effectiveness of AUD treatments, including inflated type-II error rates, particularly when treatment "success" is defined by binary outcomes such as NHDD.

Role of placebo effects in pain and neuropsychiatric disorders

The placebo (and the nocebo) effect is a powerful determinant of health outcomes in clinical disease treatment and management. Efforts to completely eradicate placebo effects have shifted dynamically, as increasingly more researchers are tuned to the potentially beneficial effects of incorporating those uncontrollable placebo effects into clinical therapeutic strategies. In this review, we highlight the major findings from placebo research, elucidating the main neurobiological systems and candidate determinants of the placebo phenomenon, and illustrate a perspective that can effectively frame future research on the topic. Finally, we issue a call for increased research on the efficacy of therapeutic strategies that incorporate placebo "tools," and argue that clinical trials of the placebo response in neuropsychiatric diseases and disorders has important and far-reaching translational and clinical relevance.

Study characteristics influence the efficacy of substance abuse treatments: A meta-analysis of medications for alcohol use disorder

BACKGROUND

Understanding study characteristics' influence on treatment efficacy could improve methodologies and interpretation of findings. We examine study characteristics as predictors of outcomes in clinical trials of medications for alcohol problems.

METHODS

We obtained data on 23 trials of naltrexone and 22 trials of acamprosate from Cochrane reviews. We extracted data for 14 study characteristics and 3 dependent variables (odds ratio; percent abstinent in placebo; medication conditions). We used general linear models to determine which study characteristics explained the variability among outcomes after controlling for medication characteristics.

RESULTS

Study characteristics accounted for 45% of the variance in odds ratio when trials of different medications were combined, 19% among acamprosate, and 48% among naltrexone trials above and beyond medication characteristics. When medications were combined, greater odds ratios were predicted by having more dropouts in the placebo than medication conditions, an earlier publication year, and not receiving industry funding. Whether this was due to effects on placebo or medication conditions was unclear. Among acamprosate trials, smaller sample sizes predicted greater odds ratios, which appeared to be due to more abstinence in medication conditions. Among naltrexone trials, greater odds ratios were predicted by having more dropouts in the placebo than medication conditions and a greater probability of randomizing participants to treatment. This appeared to be due to less abstinence in placebo conditions.

CONCLUSION

Study characteristics influence the assessment of treatment efficacy beyond medication characteristics in alcohol treatment trials. Future studies are needed to determine which study characteristics reliably influence efficacy to help investigators design and help clinicians interpret trials.

Efficacy and safety of sodium oxybate in alcohol-dependent patients with a very high drinking risk level

Medication development for alcohol relapse prevention or reduction of consumption is highly challenging due to methodological issues of pharmacotherapy trials. Existing approved medications are only modestly effective with many patients failing to benefit from these therapies. Therefore, there is a pressing need for other effective treatments with a different mechanism of action, especially for patients with very high (VH) drinking risk levels (DRL) because this is the most severely affected population of alcohol use disorder patients. Life expectancy of alcohol-dependent patients with a VH DRL is reduced by 22 years compared with the general population and approximately 90 000 alcohol-dependent subjects with a VH DRL die prematurely each year in the EU (Rehm et al. ). A promising new medication for this population is sodium oxybate, a compound that acts on GABA_B receptors and extrasynaptic GABA_A receptors resulting in alcohol-mimetic effects. In this article, a European expert group of alcohol researchers and clinicians summarizes data (a) from published trials, (b) from two new-as yet unpublished-large clinical trials (GATE 2 (n = 314) and SMO032 (n = 496), (c) from post hoc subgroup analyses of patients with different WHO-defined DRLs and (d) from multiple meta-analyses. These data provide convergent evidence that sodium oxybate is effective especially in a subgroup of alcohol-dependent patients with VH DRLs. Depending on the study, abstinence rates are increased up to 34 percent compared with placebo with risk ratios up to 6.8 in favor of sodium oxybate treatment. These convergent data are supported by the clinical use of sodium oxybate in Austria and Italy for more than 25 years. Sodium oxybate is the sodium salt of γ-hydroxybutyric acid that is also used as a recreational (street) drug suggestive of abuse potential. However, a pharmacovigilance database of more than 260 000 alcohol-dependent patients treated with sodium oxybate reported very few adverse side effects and only few cases of abuse. We therefore conclude that sodium oxybate is an effective, well-tolerated and safe treatment for withdrawal and relapse prevention treatment, especially in alcohol-dependent patients with VH DRL.

Both active and sham low-frequency rTMS single sessions over the right DLPFC decrease cue-induced cravings among pathological gamblers seeking treatment: A randomized, double-blind, sham-controlled crossover trial

Background Craving is a core symptom of addictive disorders, such as pathological gambling for example. Over the last decade, several studies have assessed the efficacy of repetitive transcranial magnetic stimulation (rTMS) in the addiction field, which triggers the dorsolateral prefrontal cortex (DLPFC) to decrease craving. The STIMJEU study investigated whether a single session of low-frequency (LF, i.e., 1 Hz) rTMS applied to the right DLPFC reduced cue-induced gambling craving in a sample of treatment-seeking pathological gamblers. Methods Thirty patients received both active and sham rTMS in random order and were blinded to the condition in a within-subject crossover design. Outcome measures included self-reported gambling craving (Visual Analog Scale and Gambling Craving Scale) and physiological measures (heart rate and blood pressure). Results The rTMS sessions were associated with a significant decrease in the gambling urge, regardless of whether the session was active or sham. When controlling cue-induced craving levels, no effects were observed on craving for active rTMS. Overall, rTMS was well-tolerated, and the credibility of the sham procedure was assessed and appeared to be appropriate. Conclusions We failed to demonstrate the specific efficacy of one session of LF rTMS to decrease cue-induced craving in pathological gamblers. A strong placebo-effect and rTMS parameters may partly explain these results. Yet, we are convinced that rTMS remains a promising therapeutic method. Further studies are required to examine its potential effect.

Precision Medicine in Alcohol Dependence: A Controlled Trial Testing Pharmacotherapy Response Among Reward and Relief Drinking Phenotypes

Randomized trials of medications for alcohol dependence (AD) often report no differences between active medications. Few studies in AD have tested hypotheses regarding which medication will work best for which patients (ie, precision medicine). The PREDICT study tested acamprosate and naltrexone vs placebo in 426 randomly assigned AD patients in a 3-month treatment. PREDICT proposed individuals whose drinking was driven by positive reinforcement (ie, reward drinkers) would have a better treatment response to naltrexone, whereas individuals whose drinking was driven by negative reinforcement (ie, relief drinkers) would have a better treatment response to acamprosate. The goal of the current analysis was to test this precision medicine hypothesis of the PREDICT study via analyses of subgroups. Results indicated that four phenotypes could be derived using the Inventory of Drinking Situations, a 30-item self-report questionnaire. These were high reward/high relief, high reward/low relief, low reward/high relief, and low reward/low relief phenotypes. Construct validation analyses provided strong support for the validity of these phenotypes. The subgroup of individuals who were predominantly reward drinkers and received naltrexone vs placebo had an 83% reduction in the likelihood of any heavy drinking (large effect size). Cutoff analyses were done for clinical applicability: individuals are reward drinkers and respond to naltrexone if their reward score was higher than their relief score AND their reward score was between 12 and 31. Using naltrexone with individuals who are predominantly reward drinkers produces significantly higher effect sizes than prescribing the medication to a more heterogeneous sample.

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.

Mecamylamine treatment for alcohol dependence: a randomized controlled trial

BACKGROUND AND AIMS

The nicotinic acetylcholine receptor antagonist, mecamylamine, is a potential novel pharmacotherapy for alcohol use disorder. The aims were to compare alcohol consumption between mecamylamine and placebo and test if smoking status modified treatment effects.

DESIGN

Out-patient, randomized, double-blind clinical trial for 12 weeks of treatment with mecamylamine (10 mg) (n = 65) versus placebo (n = 63).

SETTING

Connecticut, USA.

PARTICIPANTS

Individuals had current alcohol dependence (n = 128), had an average age of 48.5 [standard deviation (SD) = 9.4], 110 (85.9%) were men, and included 74 smokers (57.8%) and 54 non-smokers (42.2%). Participants were randomized to mecamylamine 10 mg per day or placebo. All subjects also received medical management therapy administered by trained research personnel.

MEASUREMENTS

Primary outcome was percentage of heavy drinking days during the last month of treatment; other outcomes included drinking days, drinks per drinking days, alcohol craving, smoking, symptoms of nicotine withdrawal and side effects.

FINDINGS

There were no significant differences in the percentage of heavy drinking days at 3 months between the mecamylamine (mean = 18.4, SD = 29.0) and placebo treatment groups (mean = 20.4, SD = 29.2) [F1, 100  = 1.3, P = 0.25; effect size d = 0.07; mean difference = 2.06, 95% confidence interval (CI) = -8.96 to 13.08]. There were no significant differences in percentage of drinking days or in drinks per drinking day at month 3 between the mecamylamine and placebo groups; there were no significant interactions.

CONCLUSIONS

Mecamylamine 10 mg per day did not reduce alcohol consumption significantly in treatment-seeking smokers and non-smokers with alcohol use disorder.

The placebo effect and its clinical associations in gambling disorder

BACKGROUND

Although gambling disorder is prevalent and functionally impairing, no FDA-approved medications exist for its treatment. The ability of clinical trials to detect the benefits of active treatment has been hindered by an unusually high placebo response. Virtually nothing is known about baseline clinical characteristics that might predict placebo response in those with gambling disorder.

METHODS

Participants (N = 152) assigned to placebo were pooled from multiple double-blind trials of gambling disorder. Participants were classified as placebo responders or non-responders based on a cut-off of 35% reduction in symptom severity on the Gambling Symptom Assessment Scale. Baseline group differences were characterized using t tests and equivalent non-parametric tests as appropriate.

RESULTS

Fifty-one percent of individuals assigned to placebo showed a significant clinical response. Compared with non-responders, placebo responders remained in treatment for significantly longer, were more likely to report "enjoyment" as a trigger for gambling, and were less likely to state that "boredom" or "loneliness" triggered their gambling. Placebo responders and non-responders did not differ significantly in age, sex, age at symptom onset, baseline symptom severity, comorbidities, or likelihood of having received a previous treatment.

CONCLUSIONS

Predictors of placebo response for gambling disorder appear markedly different from those reported for other mental illnesses.

Acceptability and feasibility of a randomized clinical trial of oral naltrexone vs. placebo for women living with HIV infection: Study design challenges and pilot study results

BACKGROUND

Women living with HIV/AIDS who drink alcohol are at increased risk for adverse health outcomes, but there is little evidence on best methods for reducing alcohol consumption in this population. We conducted a pilot study to determine the acceptability and feasibility of conducting a larger randomized clinical trial of naltrexone vs. placebo to reduce alcohol consumption in women living with HIV/AIDS.

METHODS

We designed the trial with input from community and scientific review. Women with HIV who reported current hazardous drinking (>7 drinks/week or ≥4 drinks per occasion) were randomly assigned to daily oral naltrexone (50mg) or placebo for 4months. We evaluated willingness to enroll, adherence to study medication, treatment side effects, and drinking and HIV-related outcomes.

RESULTS

From 2010 to 2012, 17 women enrolled (mean age 49years, 94% African American). Study participation was higher among women recruited from an existing HIV cohort study compared to women recruited from an outpatient HIV clinic. Participants took 73% of their study medication; 82% completed the final assessment (7-months). Among all participants, mean alcohol consumption declined substantially from baseline to month 4 (39.2 vs. 12.8 drinks/week, p<0.01) with continued reduction maintained at 7-months. Drinking reductions were similar in both naltrexone and placebo groups.

CONCLUSIONS

A pharmacologic alcohol intervention was acceptable and feasible in women with HIV, with reduced alcohol consumption noted in women assigned to both treatment and placebo groups. However, several recruitment challenges were identified that should be addressed to enhance recruitment in future alcohol treatment trials.

Network analysis of the genomic basis of the placebo effect

The placebo effect is a phenomenon in which patients who are given an inactive treatment (e.g., inert pill) show a perceived or actual improvement in a medical condition. Placebo effects in clinical trials have been investigated for many years especially because placebo treatments often serve as the control arm of randomized clinical trial designs. Recent observations suggest that placebo effects may be modified by genetics. This observation has given rise to the term "placebome," which refers to a group of genome-related mediators that affect an individual's response to placebo treatments. In this study, we conduct a network analysis of the placebome and identify a placebome module in the comprehensive human interactome using a seed-connector algorithm. The placebome module is significantly enriched with neurotransmitter signaling pathways and brain-specific proteins. We validate the placebome module using a large cohort of the Women's Genome Health Study (WGHS) trial and demonstrate that the placebome module is significantly enriched with genes whose SNPs modify the outcome in the placebo arm of the trial. To gain insights into placebo effects in different diseases and drug treatments, we use a network proximity measure to examine the closeness of the placebome module to different disease modules and drug target modules. The results demonstrate that the network proximity of the placebome module to disease modules in the interactome significantly correlates with the strength of the placebo effect in the corresponding diseases. The proximity of the placebome module to molecular pathways affected by certain drug classes indicates the existence of placebo-drug interactions. This study is helpful for understanding the molecular mechanisms mediating the placebo response, and sets the stage for minimizing its effects in clinical trials and for developing therapeutic strategies that intentionally engage it.

A Double-Blind Randomized Placebo-Controlled Trial of Oral Naltrexone for Heavy-Drinking Smokers Seeking Smoking Cessation Treatment

BACKGROUND

Post hoc analyses of 2 randomized controlled trials suggest naltrexone may reduce alcohol use and improve smoking cessation outcomes among heavy drinkers receiving smoking cessation treatment. However, no studies have been conducted specifically to examine naltrexone for this purpose or to test whether naltrexone has benefit when added to smoking cessation counseling that explicitly addresses heavy drinking.

METHODS

We recruited heavy-drinking smokers from the community and randomized them to receive 10 weeks of either (i) 50 mg naltrexone (n = 75) or (ii) placebo (n = 75) daily. Participants received 6 weeks of transdermal nicotine patch and 6 sessions of counseling that addressed both heavy drinking and smoking. Participants were followed for 26 weeks after their target quit smoking date.

RESULTS

Across medication conditions, there were substantial reductions at follow-up in percent heavy drinking days (primary outcome) and average drinks per week (secondary outcome). However, participants receiving naltrexone did not differ significantly from those receiving placebo on percent heavy drinking days (effect size d = -0.04, 95% CI [-0.30, 0.22], p = 0.76) or average drinks per week (d = -0.09, 95% CI [-0.35, 0.18], p = 0.54) during follow-up. Naltrexone compared to placebo was not associated with a significant increase in smoking abstinence rates during follow-up, odds ratio = 0.93, 95% CI [0.46, 1.86], p = 0.83. The effect of naltrexone on these outcomes was not significantly moderated by current alcohol dependence or gender.

CONCLUSIONS

Results indicate that heavy-drinking smokers, including those with current alcohol dependence, can make substantial reductions in drinking in the context of smoking cessation treatment. However, this study provided no evidence that naltrexone is efficacious for enhancing reductions in drinking or improving smoking cessation in this population. Limitations of this study included lower-than-desired sample size and modest adherence to study medication.

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.

Discovery, Development, and Adoption of Medications to Treat Alcohol Use Disorder: Goals for the Phases of Medications Development

For more than 25 years, advances have been made in developing medications to treat alcohol use disorder (AUD), highlighted by the U.S. Food and Drug Administration's approval of naltrexone (oral and long-acting) and acamprosate. Despite this progress, more work remains to be done in this area because these medications, although effective for some people, do not work for everyone. A high priority for the National Institute on Alcohol Abuse and Alcohol is to put into place a solid infrastructure to aid in the development of medications that are more effective than those currently available and with few side effects. Medication development, especially for a disorder as complex as AUD, is challenging and involves multiple phases, including discovery of "druggable" targets, preclinical studies, human clinical trials, and the adoption and implementation of the new medication into mainstream medicine. A successful medications development program requires clearly established goals for each phase to ensure that a candidate compound is not trapped in one particular phase, a condition known as "the valley of death." In this article, the phases of medication development are described as they apply to AUD, and specific goals of each phase are identified for the next decade. In addition, several important crosscutting themes are outlined for each phase, all of which are essential for advancing medications development. These include identifying and validating screening models and druggable targets, making use of precision medicine, and establishing partnerships among key stakeholders. Our goal in writing this article is to provide a guide on medications development that will aid the alcohol research community in planning, testing, and developing medications for AUD.

Prazosin for Veterans with Posttraumatic Stress Disorder and Comorbid Alcohol Dependence: A Clinical Trial

BACKGROUND

Posttraumatic stress disorder (PTSD) is an important and timely clinical issue particularly for combat veterans. Few pharmacologic options are available to treat PTSD, particularly among military personnel, and they are not based on rational neurobiology. The evidence for noradrenergic dysregulation in PTSD is strong, and the alpha-adrenergic agonist prazosin is one of the most promising medications to treat sleep disturbances associated with PTSD as well as PTSD symptoms among both veterans and civilians. Evidence also implicates noradrenergic dysregulation in the pathophysiology of alcohol dependence (AD); prazosin also may have efficacy in treating this disorder. The use of prazosin represents a rational and compelling approach for the treatment of PTSD and comorbid AD. Given the high rates of comorbid AD in trauma survivors with PTSD, and the enormous impact that these comorbid disorders have on psychosocial function and well-being, finding effective treatments for this population is of high clinical importance.

METHODS

Ninety-six veterans with PTSD and comorbid AD were randomized to receive prazosin (16 mg) or placebo in an outpatient, randomized, double-blind, clinical trial for 13 weeks. Main outcomes included symptoms of PTSD, sleep disturbances, and alcohol use.

RESULTS

Symptoms of PTSD improved over time, but contrary to the hypothesis, there was no medication effect on PTSD symptoms, or on sleep. Alcohol consumption also decreased over time, but there were no significant differences in outcomes between medication groups.

CONCLUSIONS

Prazosin was not effective in treating PTSD symptoms, improving sleep, or reducing alcohol consumption overall in this dually diagnosed group. This does not support the use of prazosin in an actively drinking population and suggests that the presence of a comorbid condition affects the efficacy of this medication. This study highlights the importance of conducting clinical trials in "real-world" patients, as results may vary based on comorbid conditions.

Age and sex as moderators of the placebo response – an evaluation of systematic reviews and meta-analyses across medicine

Predictors of the placebo response (PR) in randomized controlled trials (RCT) have been searched for ever since RCT have become the standard for testing novel therapies and age and gender are routinely documented data in all trials irrespective of the drug tested, its indication, and the primary and secondary end points chosen. To evaluate whether age and gender have been found to be reliable predictors of the PR across medical subspecialties, we extracted 75 systematic reviews, meta-analyses, and meta-regressions performed in major medical areas (neurology, psychiatry, internal medicine) known for high PR rates. The literature database used contains approximately 2,500 papers on various aspects of the genuine PR. These ‘meta-analyses’ were screened for statistical predictors of the PR across multiple RCT, including age and gender, but also other patient-based and design-based predictors of higher PR rates. Retrieved papers were sorted for areas and disease categories. Only 15 of the 75 analyses noted an effect of younger age to be associated with higher PR, and this was predominantly in psychiatric conditions but not in depression, and internal medicine but not in gastroenterology. Female gender was associated with higher PR in only 3 analyses. Among the patient-based predictors, the most frequently noted factor was lower symptom severity at baseline, and among the design- based factors, it was a randomization ratio that selected more patients to drugs than to placebo, more frequent study visits, and more recent trials that were associated with higher PR rates. While younger age may contribute to the PR in some conditions, sex does not. There is currently no evidence that the PR is different in the elderly. PR are, however, markedly influenced by the symptom severity at baseline, and by the likelihood of receiving active treatment in placebo- controlled trials.

Recommendations for the Design and Analysis of Treatment Trials for Alcohol Use Disorders

BACKGROUND

Over the past 60 years, the view that "alcoholism" is a disease for which the only acceptable goal of treatment is abstinence has given way to the recognition that alcohol use disorders (AUDs) occur on a continuum of severity, for which a variety of treatment options are appropriate. However, because the available treatments for AUDs are not effective for everyone, more research is needed to develop novel and more efficacious treatments to address the range of AUD severity in diverse populations. Here we offer recommendations for the design and analysis of alcohol treatment trials, with a specific focus on the careful conduct of randomized clinical trials of medications and nonpharmacological interventions for AUDs.

METHODS

This paper provides a narrative review of the quality of published clinical trials and recommendations for the optimal design and analysis of treatment trials for AUDs.

RESULTS

Despite considerable improvements in the design of alcohol clinical trials over the past 2 decades, many studies of AUD treatments have used faulty design features and statistical methods that are known to produce biased estimates of treatment efficacy.

CONCLUSIONS

The published statistical and methodological literatures provide clear guidance on methods to improve clinical trial design and analysis. Consistent use of state-of-the-art design features and analytic approaches will enhance the internal and external validity of treatment trials for AUDs across the spectrum of severity. The ultimate result of this attention to methodological rigor is that better treatment options will be identified for patients with an AUD.

Placebo eff ects in psychiatry: mediators and moderators

A strong placebo response in psychiatric disorders has been noted for the past 50 years and various attempts have been made to identify predictors of it, by use of meta-analyses of randomised controlled trials and laboratory studies. We reviewed 31 meta-analyses and systematic reviews of more than 500 randomised placebo-controlled trials across psychiatry (depression, schizophrenia, mania, attention-deficit hyperactivity disorder, autism, psychosis, binge-eating disorder, and addiction) for factors identified to be associated with increased placebo response. Of 20 factors discussed, only three were often linked to high placebo responses: low baseline severity of symptoms, more recent trials, and unbalanced randomisation (more patients randomly assigned to drug than placebo). Randomised controlled trials in non-drug therapy have not added further predictors, and laboratory studies with psychological, brain, and genetic approaches have not been successful in identifying predictors of placebo responses. This comprehensive Review suggests that predictors of the placebo response are still to be discovered, the response probably has more than one mediator, and that different and distinct moderators are probably what cause the placebo response within psychiatry and beyond.

The impact of focusing a program to prevent heavier drinking on a pre-existing phenotype, the low level of response to alcohol

BACKGROUND

Heavy drinking is common during transitions from high school to college. Optimal programs for diminishing risks for high alcohol consumption often tailor the approach to the specific needs of students. This study describes the results of an Internet-based prevention protocol that tailors the information to the risk associated with a pre-existing phenotype, the Low level of Response (Low LR) to alcohol.

METHODS

Using stratified random assignment, 454 freshmen with Low and High LR values were assigned to 2 education groups (LR-based where all examples were given the context of the Low LR model of heavy drinking or a State Of The Art (SOTA) Group where the same lessons were taught but without an emphasis on LR) or a no-intervention Control Group. Individuals in the 2 education groups viewed 50-minute online videos once per week for 4 weeks. Changes in drinking patterns were assessed at Baseline, 4 weeks, and 8 weeks using a 2 (LR status) by 3 (education group) by 3 (time points) analysis of variance, with additional tests for ethnicity and sex.

RESULTS

Low LR participants tended to decrease their usual (p < 0.06) and maximum (p < 0.05) drinks per occasion most prominently when assigned to the LR-based protocol, while those with High LRs improved more in the SOTA Group. The most robust differences were seen when controlling for ethnicity. The effect sizes were small to medium.

CONCLUSIONS

These results support the advantages of carrying out prevention via the Internet and in tailoring the approach to a pre-existing phenotype.

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.

Alcohol use disorder: pathophysiology, effects, and pharmacologic options for treatment

Alcohol use disorders (AUD) continue to be a concerning health issue worldwide. Harmful alcohol use leads to 2.5 million deaths annually worldwide. Multiple options exist for the management of dependence on alcohol, not all of which are approved by drug-regulating agencies. Current practice in treating AUD does not reflect the diversity of pharmacologic options that have potential to provide benefit, and guidance for clinicians is limited. Few medications are approved for treatment of AUD, and these have exhibited small and/or inconsistent effects in broad patient populations with diverse drinking patterns. The need for continued research into the treatment of this disease is evident in order to provide patients with more specific and effective options. This review describes the neurobiological mechanisms of AUD that are amenable to treatment and drug therapies that target pathophysiological conditions of AUD to reduce drinking. In addition, current literature on pharmacologic (both approved and non-approved) treatment options for AUD offered in the United States and elsewhere are reviewed. The aim is to inform clinicians regarding the options for alcohol abuse treatment, keeping in mind that not all treatments are completely successful in reducing craving or heavy drinking or increasing abstinence.