Atypical antipsychotics have been found not only to be beneficial in the treatment of psychotic disorders, but even for depressive symptoms in patients with schizophrenia. Remarkably, preliminary data suggest that the atypical antipsychotic quetiapine has antidepressive properties. Until now, there is limited knowledge concerning the efficacy of quetiapine in major depressive illness and especially in psychotic depression. In our own clinical practice, several patients with psychotic depression were successfully treated with quetiapine as add-on therapy or as monotherapy. On the background of that, the convincing effects of quetiapine in bipolar depression, single-case reports and pilot studies concerning its effectiveness in depressive mood states in psychotic disorders as well as our clinical experiences, it is to assume that a treatment with quetiapine over a 6 weeks period show similar effects in major depressive episode with psychotic features, i.e. psychotic depression. In this pilot study we plan to investigate 20 patients with psychotic features of depression under treatment with quetiapine.

Inclusion Criteria:

• provision of written informed consent
• diagnosis of depression with psychotic features by DSM-IV (296.23, 296.33)
• females and males aged 18 to 65 years
• female patients of childbearing potential must be using a reliable method of contraception and have a negative pregnancy test at enrollment
• patients must be able to understand and comply with the requirements of the study
• MADRS score above 20 points

Exclusion Criteria:

• pregnancy or lactation
• any DSM-IV Axis I disorder not defined in the inclusion criteria or not in full remission
• 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, as judged by the investigator
• use of any cytochrome P450 3A4 inhibitors in the 14 days preceding enrollment
• use of any cytochrome P450 inducers in the 14 days preceding enrollment
• thyroid-stimulating hormone (TSH) concentration more than 10% above the upper limit of the normal range at enrollment
• administration of a depot antipsychotic injection within one dosing interval before randomisation
• substance or alcohol dependence at enrollment, as defined by DSM-IV
• 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
• risk of transmitting human immunodeficiency virus (HIV) or hepatitis B via blood or other body fluids
• unstable or inadequately treated medical illness, as judged by the investigator
• patients with diabetes mellitus (DM)
• an absolute neutrophil count (ANC) < 1.5x10E9 per liter
• history of idiopathic orthostatic hypotension, or condition that would predispose to
• ECG considered to show clinically significant abnormalities at enrollment as determined by a cardiologist
• involvement in the planning and conduct of the study
• previous enrollment or randomisation of treatment in the present study
• any serious and unstable somatic illness that, in the opinion of the investigator, would be negatively affects by the study medication
• participation in another drug trial within 4 weeks prior to enrollment into this study
• patients with unsufficient knowledge of the German language