A Placebo Controlled Study Evaluating Efficacy, Safety and Tolerability of Medication in Patients with Major Depressive Disorder (MDD)

Inclusion Criteria:

• Diagnosis of Major Depressive Disorder (MDD)
• Duration of current depressive episode 12 weeks - 24 months
• Patients can read and write at a level sufficient to provide a signed consent
• If female, patients must be practicing an acceptable method of birth control

Exclusion Criteria:

• Patients have other psychiatric disorders that would affect patient's response to treatment
• Patients have not responded to two or more adequate courses of antidepressant therapy
• Patients cannot be currently abusing illicit drugs or alcohol
• Patients are not currently receiving psychotherapy
• Patients have received electroconvulsive therapy within 6 months prior to screening
• Patients are pregnant or lactating