Major Depressive Disorder Study In Adults

Inclusion Criteria:

• Patient must have primary diagnosis of Major Depressive Disorder (MDD).

• Discontinued a selective serotonin reuptake inhibitor (SSRI)orserotonin-norepinephrine reuptake inhibitor (SNRI) regimen due to intolerability.

• Minimum time frame between last dose of previous antidepressant and initiation ofstudy drug is one week.

• Maximum time frame between last dose of prior antidepressant and initiation of studydrug is 2 months.

Exclusion Criteria:

• Patient has previously been treated with the study drug.

• Is experiencing an adverse event attributed to previous SSRI/SNRI use that has notbeen resolved at least one week prior to Baseline Visit.

• Has a history of seizure disorder.

• Has met criteria for substance abuse or dependence within 6 months prior to BaselineVisit.

• Currently using an antidepressant.

• Currently pregnant.