A Study Of New Medicine (GSK 372475) For The Treatment Of Depression

Inclusion Criteria: * Major depressive episode (MDE) associated with Major Depressive Disorder (DSM-IV-TR criteria) * Duration of current episode is at least 12 weeks duration and less than 2 years * Symptoms of decreased energy, pleasure, and interest * Female subjects who agree to use acceptable methods of birth control throughout the study Exclusion criteria: * Current diagnosis of Panic Disorder, or symptoms of generalized anxiety or panic attacks that could interfere with their ability to complete the trial * Symptoms of MDE better accounted for by another diagnosis * Diagnosis of Bipolar, schizophrenia, other psychotic disorder(s), borderline or antisocial personality disorder, or dementia. * Started psychotherapy within 3 months prior to the Screening * Received electroconvulsive therapy or transcranial magnetic stimulation within 6 months prior to screening * Received psychoactive drugs within 4 weeks of randomization * Positive urine drug screen or positive blood alcohol * Suicidal risk or has had any previous suicide attempt, a family history of suicide attempt * Positive pregnancy test * History of seizure disorder, myocardial infarction (\< 1yr), or unstable medical condition * Failed to respond to an adequate course of pharmacotherapy of at least 2 different antidepressants