This is an explorative controlled study with Oxcarbazepine (OXC) as an adjunct in the acute treatment of schizophrenia. The study will be performed in subjects between 18 and 50 years of age with an acute schizophrenic or schizophreniform disorder according to DSM-IV. The study will be performed according to Guidelines for Good Clinical Practice (GCP).
The primary hypothesis of this study is that adjunctive treatment with OXC yields at least comparable efficacy regarding antipsychotic actions with lower doses of neuroleptics and consequently substantially fewer adverse events.
A randomised controlled, double blind study is intended. During a 6 weeks treatment trial two groups of patients will be basically treated with olanzapine (starting with 5 mg after one week with an optional, BPRS-controlled step by step increase of about 2,5 mg each following week). Patients will receive a placebo controlled adjunctive therapy with OXC (1800 mg/day). After the initial lead-in of OXC within 7 days (allowing lorazepam as comedication), treatment with olanzapine will be started. Based on biometric calculations, a drop out adjusted sample size of 222 inpatients will be necessary