A Study in Prevention of Re-emergence of Depression Symptoms

Inclusion Criteria:

• Outpatients with clinical diagnosis of Major Depressive Disorder (MDD)

• Using a reliable method of birth control

• Are taking a selective serotonin reuptake inhibitor (SSRI) approved for MDD treatmentwithin the participant's country and the SSRI prescribed, including dose, should beconsistent with labeling guidelines within the participating country

• Have a partial response to SSRI treatment

• Meet inclusion scores on pre-defined psychiatric scales to assess diagnosis ofdepression, disease severity, and response to SSRI treatment

• Reliable and able to keep all scheduled appointments

• Have had at least 1 previous episode of MDD prior to the current episode within thepast 5 years

Exclusion Criteria:

• Have had or currently have any additional ongoing Diagnostic and Statistical Manual ofMental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) Axis 1 condition otherthan major depression within 1 year of screening

• Have a current or any previous diagnosis of a bipolar disorder, schizophrenia, orother psychotic disorder

• Have a history of substance abuse and/or dependence within the past 1 year (drugcategories defined by DSM-IV-TR), not including caffeine and nicotine.

• Have a DSM-IV-TR Axis II disorder that, in the judgment of the investigator, wouldinterfere with compliance with protocol

• Have any diagnosed medical condition which could be exacerbated by noradrenergicagents, including unstable hypertension, unstable heart disease, tachycardia,tachyarrhythmia, narrow-angle glaucoma, or history of urinary hesitation or retention

• Have initiated or discontinued hormone therapy (including birth control or thyroidhormone) within the previous 3 months prior to enrollment

• Have a lifetime history of vagal nerve stimulation (VNS), transcranial magneticstimulation (TMS), or psychosurgery

• Have received electroconvulsive therapy (ECT) in the past year

• Have a serious or unstable medical condition

• Have a history of seizure disorders

• Have initiated psychotherapy, change in intensity of psychotherapy or other nondrugtherapies (such as acupuncture or hypnosis) within 6 weeks prior to enrollment or anytime during the study

• Participants who, in the opinion of the investigator, are judged to be at serious riskfor harm to self or others

• Are pregnant or breastfeeding

• Meet criteria for treatment-resistant depression