A pilot study of oxcarbazepine versus acamprosate in alcohol-dependent patients

This pilot study has been designed to collect preliminary data on the use of a new antiepileptic drug in the management of alcoholic patients. Oxcarbazepine (OXC) blocks voltage-sensitive sodium channels. Its metabolite reduces high-voltage-activated calcium currents in striatal and cortical neurons, thus reducing glutamatergic transmission at corticostriatal synapses. This reduction is of interest in the treatment of alcohol dependence, as acamprosate (ACP) modulates NMDA receptors, resulting in an inhibition of glutamatergic transmission. Furthermore, OXC has revealed a mood-stabilizing effect in bipolar affective disorders. We have compared OXC with ACP in relapse prevention in recently withdrawn alcohol-dependent patients.

We investigated the efficacy and safety of OXC (vs ACP) by conducting a 24-week randomized, parallel-group, open-label, clinical trial on 30 acutely detoxified alcoholic patients. Survival analyses (Kaplan-Meier) were performed to look for evidence of a longer "survival" of patients receiving OXC. We assessed time to first severe relapse and additional secondary endpoints.

After withdrawal, time to severe relapse and time to first consumption of any ethanol by OXC patients were not longer than for ACP patients. Abstinent patients in both study groups showed a significantly lower obsessive compulsive drinking scale-German version (OCDS-G) than relapsed patients. No undesired effects occurred when OXC patients consumed alcohol.

Our findings indicate that it could be worthwhile to test relapse prevention using OXC in an adequate sample. While the current sample size clearly limits further conclusions from this pilot study, it is noteworthy that OXC is well tolerated, even when alcohol is on board. Thus, in medication-based relapse prevention, OXC could be a promising alternative for alcoholic patients unable to benefit from ACP or naltrexone or those who have affective liability. OXC certainly merits a larger placebo-controlled trial.