A Four-week Clinical Trial Investigating Efficacy and Safety of Cannabidiol As a Treatment for Acutely Ill Schizophrenic Patients

Inclusion Criteria: * Informed consent given by the subject * DSM-IV-TR diagnosis of schizophrenic psychosis (295.10, 295.20, 295.30, 295.90 (American Psychiatric Association) * Patients must be within the first three years of illness, i.e. first diagnosis of schizophrenia is no older than three years. * Age 18 to 65 years, male or female * Minimal initial PANSS score of 75 at baseline * Female patients of childbearing potential need to utilize a proper method of contraception. * Body Mass Index between 18 and 40 Exclusion Criteria: * Lack of accountability (assessed by an independent psychiatrist) * History of treatment-resistant schizophrenia, defined as no response to at least two antipsychotics given for a minimum of 6 weeks each in an adequate dosage * Positive urine drug-screening for illicit drugs at screening (except cannabinoids and benzodiazepines) * Serious suicidal risk at screening visit (Subject to investigator's and independent psychiatrist's judgement: Poses a serious suicidal or homicidal risk at screening visit or has made a serious suicide attempt within the last 12 months prior to screening visit, or has exhibited homicidal behaviour at anytime during her/his lifetime) * Known intolerance or allergy to olanzapine or cannabidiol * Other relevant interferences of axis 1 (e.g. serious depression) according to diagnostic evaluation (MINI) including residual forms of schizophrenia * Pregnancy, as determined through a β-HCG pregnancy test, or lactation