HAM-D17 is a standardized, clinician-administered rating scale that assesses 17 items characteristically associated with major depression. Items are scored on either a 3-point (0 to 2) or a 5-point scale (0 to 4) with 0=none/absent and 4=most severe, for a maximum total score of 50. Higher scores indicate greater severity. FOT evaluation is defined as the last "on-therapy" evaluation, regardless of the number of days on therapy. Analysis on Observed cases (non-missing data) and Last observation carried forward (LOCF); LOCF method of imputation for any missing value at any visit.

Intent to treat (ITT): all enrolled participants who received at least 1 dose of study treatment in Extension Study and at least 1 available post-baseline evaluation for any endpoint; (n)=number of participants with analyzable data at observation.

CGI-I is a 7-point clinician rated scale ranging from 1 (very much improved) to 7 (very much worse). Improvement is defined as a score of 1 (very much improved), 2 (much improved), or 3 (minimally improved) on the scale. Higher score = more affected.

ITT; LOCF. Improvement measured against CGI-I baseline (Day -1) data in Core study (NCT00798707 [3151A1-3359 / B2061003]).

CGI-S is a 7-point clinician rated scale to assess severity of current illness state. Range is 1 (normal - not ill at all) to 7 (among the most extremely ill). Higher score = more affected.

ITT; LOCF and Observed cases (non-missing data); (n)=number of participants with analyzable data at observation.

Any untoward medical occurrence in a participant who received study treatment was considered an AE without regard to possibility of causal relationship. An AE resulting in any of the following outcomes, or deemed to be significant for any other reason, was considered to be an SAE: death; initial or prolonged inpatient hospitalization; a life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; or congenital anomaly.

Safety population: all enrolled participants who received at least 1 dose of study treatment in this extension study.