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.

AUD in perspective.

Alcohol is a major cause of pre-mature death and individual suffering worldwide, and the importance of diagnosing and treating AUD cannot be overstated. Given the global burden and the high attributable factor of alcohol in a vast number of diseases, the need for additional interventions and the development of new medicines is considered a priority by the World Health Organization (WHO). As of today, AUD is severely under-treated with a treatment gap nearing 90%, strikingly higher than that for other psychiatric disorders. Patients often seek treatment late in the progress of the disease and even among those who seek treatment only a minority receive medication, mirroring the still-prevailing stigma of the disease, and a lack of access to effective treatments, as well as a reluctance to total abstinence. To increase adherence, treatment goals should focus not only on maintaining abstinence, but also on harm reduction and psychosocial functioning. A personalised approach to AUD treatment, with a holistic view, and tailored therapy has the potential to improve AUD treatment outcomes by targeting the heterogeneity in genetics and pathophysiology, as well as reason for, and reaction to drinking. Also, the psychiatric co-morbidity rates are high in AUD and dual diagnosis can worsen symptoms and influence treatment response and should be considered in the treatment strategies.

Substitution therapy for patients with alcohol dependence: Mechanisms of action and efficacy.

New approaches for the treatment of alcohol dependence (AD) may improve patient outcomes. Substitution maintenance therapy is one of the most effective treatment options for opioid and nicotine use disorders. So far, there has been little attention to substitution therapy for the treatment of AD. Here, we explain the mechanistic foundations of alcohol substitution maintenance therapy. Alcohol has many primary targets in the brain (and other organs) and the physical interaction of ethanol molecules with these specific ethanol-sensitive sites on a variety of ionotropic receptors (e.g. GABA-A, NMDA, and nicotinic acetylcholine (nACh) receptors) and ion channels provides the rationale for substitution. As such, a variety of compounds can interact with those ethanol-sensitive sites and can thus substitute for some of the effects of alcohol. For some of these compounds, alcohol discrimination studies have shown their substitution potential. Accordingly, potential substitution treatments include agonists acting at GABA receptors such as sodium oxybate, baclofen and benzodiazepines, NMDA receptor antagonists such as ketamine and memantine, or nAChRs agonists such as varenicline. All these compounds are already approved for other indications and we present clinical evidence for these drugs in the treatment of alcohol withdrawal syndrome (AWS) and in the long-term treatment of AD, and outline future steps for their acceptance as substitution treatment in AD. Finally, we discuss the substitution approach of managed alcohol programs for the most severely affected homeless populations. Results showed that sodium oxybate is probably the closest to a substitution therapy for AD and is already approved for the treatment of AWS and in the long-term treatment of AD in some countries. In conclusion, we argue that better AD treatment can be provided if substitution maintenance treatments for alcohol are implemented at a similar scale as for opioid and nicotine use disorder.

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.

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.

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.

Alcohol dependence and very high risk level of alcohol consumption: a life-threatening and debilitating disease.

Women and men with alcohol dependence and very high risk drinking level (VHRDL; defined as drinking >60 or 100 g of ethanol per day, respectively) experience severe health consequences; however, data on the number of these individuals and their health risks are limited. This study estimated (1) the prevalence of VHRDL in 13 European Union (EU) countries among people 15-65 years of age, (2) the risk of disease and injury occurrence associated with VHRDL, (3) the proportion of deaths in nine EU countries attributable to VHRDL and (4) the life expectancy of people in France with VHRDL. Prevalence estimates of VHRDL were based on data obtained from clinical trials and the Global Information System on Alcohol and Health. The risk of disease and injury occurrence was estimated using microsimulations. Population-attributable fractions (PAFs) were estimated using a Levin-based methodology. The estimated prevalence of VHRDL in the 13 EU countries examined was 0.74-0.85 percent, with a disease and injury occurrence risk of 13.5 per 100 people with VHRDL per year. For the nine EU countries examined, VHRDL caused 53.6 percent of all liver cirrhosis, 43.8 percent of all pancreatitis and 41.1 percent of oral cavity and pharyngeal cancers (all other PAFs were below 30 percent). Applying these PAFs to French mortality data resulted in a life expectancy of 47-61 years for people with VHRDL-21-35 years less than the general population. These results indicate that the health burdens of VHRDL are potentially large, and interventions targeting VHRDL should be considered when formulating public health policies.