The study evaluated the long-term safety of Desvenlafaxine Succinate (DVS) Slow Release (SR) during open-label treatment in adult outpatients who had a primary diagnosis of major depressive disorder (MDD). The study also evaluated the long-term response of subjects receiving DVS SR for clinical global evaluation, functionality, general well-being, pain, and absence of depressive symptoms (remission).

Inclusion Criteria:

• Outpatients who have completed double-blind therapy in a phase 3 DVS-233 SR short-term study for the indication of MDD, including scheduled evaluations, with no major protocol violations and no study events that, in the opinion of the investigator, would preclude the subject's entry into the long-term, open-label study.
• Sexually active individuals participating in the study must use a medically acceptable form of contraception during the trial and for at least 15 days after the last dose of study drug.

Exclusion Criteria:

• Clinically important abnormalities on baseline physical examination, or any unresolved clinically significant abnormalities on ECG, laboratory test results, or vital signs recorded in a previous phase 3 DVS-233 SR short-term study for the indication of MDD. Any exception must be discussed with and granted by the sponsor.
• Significant risk of suicide based on clinical judgment, including common suicidal thoughts, and suicide being considered as a possible solution, even without specific plans or intention.
• Presence of clinically important hepatic or renal disease or other medical disease that might compromise the study or be detrimental to the subject (eg, clinically important cardiac arrhythmia, uncontrolled diabetes, uncontrolled hypertension, seizure disorder, myocardial infarction, neurologic disorder, acute illness, neoplastic disorder).