Acamprosate for the Treatment of Alcohol Dependence: A Review of Double-Blind, Placebo-Controlled Trials

Acamprosate (calcium acetyl-homotaurine) is a synthetic compound that crosses the blood-brain barrier and has a chemical structure similar to that of the naturally occurring amino acid neuromediators, homotaurine and γ-aminobu-tyric acid (GABA). Acamprosate appears to act primarily by restoring normal N-methyl-D-aspartate (NMDA) receptor tone in the glutamate system, and has been shown to have a specific dose-dependent effect on decreasing voluntary alcohol intake in animals with no effects on food and water consumption. The safety and efficacy of acamprosate in alcohol-dependent outpatients is currently under evaluation in the United States. Acamprosate has been available by prescription since 1989 in France and more recently in most European and Latin American coutries as well as Australia, South Africa, and Hong Kong. More than 4 million people have been treated with acamprosate since it became commercially available.The purpose of this article is to review all available double-blind, placebo-controlled clinical trials evaluating the safety and efficacy of acamprosate treatment of alcohol dependence. This work encompasses 16 controlled clinical trials conducted across 11 European countries and involves more than 4,500 outpatients with alcohol dependence. Fourteen of 16 studies found alcohol-dependent patients treated with acamprosate had a significantly greater rate of treatment completion, time to first drink, abstinence rate, and/or cumulative abstinence duration than patients treated with placebo. Additionally, a multinational open-label study of acamprosate in 1,281 patients with alcohol dependence found acamprosate to be equally effective across four major psychosocial concomitant treatment programs in maintaining abstinence and reducing consumption during any periods of relapse. An absence of known strong predictors of response to acamprosate, in conjunction with a modest but consistent effect on prolonging abstinence, and an excellent safety profile, lend support to the use of acamprosate across a broad range of patients with alcohol dependence.