Predictors of acamprosate efficacy: Results from a pooled analysis of seven European trials including 1485 alcohol-dependent patients

Department of Clinical Psychology, University of Amsterdam , Amsterdam, The Netherlands.
Psychopharmacology (Impact Factor: 3.88). 04/2005; 178(2-3):167-73. DOI: 10.1007/s00213-004-1991-7
Source: PubMed


Acamprosate is a proven effective intervention in the treatment of alcohol dependence. However, acamprosate prevents lapses or relapses only in a minority of patients. An important question, therefore, is whether there is a specific subgroup of patients who respond particularly well to acamprosate.
To identify predictors of acamprosate efficacy. Based upon the available evidence and hypotheses about the mechanisms underlying acamprosate's effects on drinking behavior, the following variables were considered to be potential positive predictors: high physiological dependence at baseline, negative family history of alcoholism, late age-of-onset, serious anxiety symptomatology at baseline, severe craving at baseline, and female gender.
Potential predictors of acamprosate's efficacy were analyzed in a pooled analysis of data from seven randomized placebo-controlled trials involving a total of 1485 patients with alcohol dependence. Outcome is measured in terms of cumulative abstinence duration (CAD), continuous abstinence (ABST), and time to first relapse (TFR).
CAD and ABST were predicted by baseline measures of craving and anxiety, as well as by study and treatment condition. Acamprosate efficacy was not differentially associated with any of the predictor variables. Importantly, the hypotheses were rejected despite the large sample size and sufficient statistical power.
The most straight-forward clinical implication of this study is that acamprosate can be considered as a potentially effective pharmacotherapy for all patients with alcohol dependence. The effect size of acamprosate alone is, however, moderate. Some evidence indicates that the combination of acamprosate with naltrexone or disulfiram leads to substantially better outcomes.

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    • "However, evidence from meta-analyses has not been found in support of this (NICE, 2011a; Verheul et al., 2005) (Ia). Verheul et al. (2005) (Ia) indeed concluded that acamprosate is potentially effective for anyone with alcohol dependence. At the time of writing these guidelines, a large prospective study set up to define if there are any subgroups who respond to either acamprosate or naltrexone, 'project PREDICT' has yet to formally publish its results (Mann et al., 2009) (Ib). "
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    • "ACAMP has also been found to be preferentially effective in alcohol-dependent subjects that obtained low scores on somatic distress (Kiefer et al., 2005). However, Verheul et al. (2005) in a pooled analysis of seven European trials including 1485 patients found that ACAMP was not differentially associated with any predictor variables including physiological dependence, familial alcoholism, age-of-onset, anxiety symptomatology, severity of craving or gender. Another pooled analysis of European trials (Sass et al., 1995) similarly failed to find any predictors of efficacious response to ACAMP on any baseline characteristics. "
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