- Adult, outpatient with primary diagnosis of Major Depressive Disorder (depressive
symptoms for at least 30 days prior to screening).
- Hamilton Psychiatric Rating Scale for Depression (HAM-D 17) total score of >= 20.
- Clinical Global Impressions Scale-Severity (CGI-S) score of >= 4.
- Clinical instability (25% or greater increase/decrease in HAM-D 17 total score from
screening to baseline).
- Significant risk of suicide as assessed by clinician judgment, HAM-D 17 and Columbia
Suicide-Severity Rating Scale scores Other eligibility criteria also apply.