The Quietude Study: Quetiapine Use for Agitated Depression

Inclusion Criteria: * Male or female * Age 18 to 65 * Outpatient at enrolment * A diagnosis of major depressive disorder * Baseline HAMD-17 score \> 20 and HAMD Item1 score \> 2 both at enrolment and baseline * Significant agitation * CGI-S score \> 4 at screening and baseline * Negative serum pregnancy test at enrolment and use of a reliable method of birth control during the study * Able to understand and comply with the requirements of the study * Able and willing to give meaningful informed written consent Exclusion Criteria: * Another Axis I diagnosis of primary focus within 6 months of enrolment * Axis II disorder causing impact on current diagnosis * Current depressive episode \<4 weeks, or \>12 months * Substance or alcohol abuse or dependency as defined by DSM IV within 6 months of enrolment * Any pervasive developmental disorder or dementing disorder * Treatment with other antipsychotics, mood stabilizer or other psychoactive drugs less than 7 days prior to randomization * Treatment with fluoxetine less than 28 days prior to baseline * Treatment with MAO inhibitors, anxiolytic drugs in excess of 2 mg lorazepam equivalents/day. * Insufficient response to more than two antidepressants during the index episode prior to study involvement * Known lack of antidepressant response to quetiapine at a dose of at least 50 mg/day x 4 weeks * Known lack of antidepressant response to escitalopram at a dose of at least 10 mg/day * Known intolerance or hypersensitivity to quetiapine or escitalopram * Treatment with Electroconvulsive therapy within 90 days prior to baseline * Use of Potent P450 3A4 inhibitors or inducers within 14 days of baseline * AST \& ALT ≥ 3X ULN * TSH ≥ 10% ULN * Unstable medical condition * Medical condition the would affect absorption, distribution, metabolism or excretion of study treatment * Significant ECG abnormalities * Pregnancy or lactation * Patients with increased suicidal risks, HAM-D item 3 ≥3 or have made a suicide attempt within the past 6 months. * Patients who, in the investigators opinion, will require psychotherapy (other than supportive psychotherapy) during the study period, unless psychotherapy has been ongoing for a minimum of 3 months prior to randomisation * A patient with Diabetes Mellitus (DM) fulfilling one of the following criteria: * Unstable DM defined as enrolment glycosylated haemoglobin (HbA1c) \>8.5%. * Admitted to hospital for treatment of DM or DM related illness in past 12 weeks. * Not under physician care for DM. * Physician responsible for patient's DM care has not indicated that patient's DM is controlled. * Physician responsible for patient's DM care has not approved patient's participation in the study * Has not been on the same dose of oral hypoglycaemic drug(s) and/or diet for the 4 weeks prior to randomisation. For thiazolidinediones (glitazones) this period should not be less than 8 weeks. * Taking insulin whose daily dose on one occasion in the past 4 weeks has been more than 10% above or below their mean dose in the preceding 4 weeks Note: If a diabetic patient meets one of these criteria, the patient is to be excluded even if the treating physician believes that the patient is stable and can participate in the study * Clinically significant deviation from the reference range in clinical laboratory test results * An absolute neutrophil count (ANC) of 1.5 x 109 per liter * Those who are involved in the planning and/or conduct of the study cannot be enrolled as subjects * Previous enrolment or randomization in the present study * Participation in another medication trial within 4 weeks prior to enrolment into the study herein