OBJECTIVE: The present observational cohort study documented the safety of agomelatine in current medical practice in out-patients suffering from major depressive disorder. METHOD: The 6-month evolution of agomelatine-treated patients was assessed with a focus on safety (emergent adverse events, liver acceptability), severity of depression using the Clinical Global Impression Severity (CGI-S) score, and functioning measured by the Sheehan Disability Scale (SDS). RESULTS: A total of 8453 depressed patients from 761 centres in 6 countries were analysed (female: 67.7%; mean age: 49.1 ± 14.8 years). Adverse events reported were in accordance with the known safety profile of agomelatine. Cutaneous events were reported in 1.7% of the patients and increased hepatic transaminases values were reported in 0.9 % of the patients. The incidence of events related to suicide/self-injury was 1.0%. Two completed suicides, not related to the study drug, were reported. CGI-S total scores and SDS sub-scores improved and numbers of days lost or underproductive decreased over the treatment period. CONCLUSIONS: In standard medical practice, agomelatine treatment was associated with a low incidence of side effects. No unexpected events were reported. A decrease in the severity of the depressive episode and improved functioning were observed. TRIAL REGISTRATION NAME: Observational cohort study to evaluate the safety of agomelatine in standard medical practice in depressed patients. A prospective, observational (non-interventional), international, multicentre cohort study. TRIAL REGISTRATION NUMBER: ISRCTN53570733.Read less <