Genes, Intermediate Phenotypes and Response to Quetiapine RX

Inclusion Criteria:

• Provision of written informed consent
• Diagnosis of schizophrenia using the Structured Clinical Interview for Diagnosis for the Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition
• Male or female patients aged between 18 and 65 years
• Female patients of childbearing potential must be using a reliable method of contraception and have a negative urine human chorionic gonadotropin test at enrollment
• Able to understand and comply with the requirements of the study
• Patients with a cut off value for PANSS more than 75

Exclusion Criteria:

• Pregnancy or lactation
• Any DSM-IV Axis I disorder not defined in the inclusion criteria
• Patients who, in the opinion of the investigator, pose an imminent risk of suicide or a danger to self or others
• Known intolerance or lack of response to quetiapine fumarate, as judged by the investigator
• Use of any of the following cytochrome P450 3A4 inhibitors in the 14 days preceding enrollment including but not limited to: ketoconazole, itraconazole, fluconazole, erythromycin, clarithromycin, troleandomycin, indinavir, nelfinavir, ritonavir, fluvoxamine and saquinavir
• Use of any of the following cytochrome P450 inducers in the 14 days preceding enrollment including but not limited to: phenytoin, carbamazepine, barbiturates, rifampin, St. John's Wort, and glucocorticoids
• Administration of a depot antipsychotic injection within one dosing interval before randomization
• Patients treated with clozapine within 28 days before the enrollment
• Substance or alcohol dependence at enrollment (except dependence in full remission, and except for caffeine or nicotine dependence)
• Opiates, amphetamine, barbiturate, cocaine, cannabis, or hallucinogen abuse by DSM-IV criteria within 4 weeks prior to enrollment
• Medical conditions that would affect absorption, distribution, metabolism, or excretion of study treatment
• Unstable or inadequately treated medical illness (e.g. diabetes, angina pectoris, hypertension) as judged by the investigator
• Involvement in the planning and conduct of the study
• Previous enrollment or randomization of treatment in the present study
• Participation in another drug trial within 4 weeks prior to enrollment into this study or longer in accordance with local requirements
• A patient with Diabetes Mellitus
• An absolute neutrophil count of ¬1.5 x 109 per liter
• Pre-existing Organic Mental Disorder or Mental Retardation.