Study: NCT02418585

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Esketamine
Description: Participants will self-administer either 56 mg or 84 mg of esketamine, intranasally, twice per week as a flexible dose regimen in the Double-Blind Induction Phase.

Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: Placebo
Description: Participants will self-administer matching placebo, intranasally, twice per week for 4 weeks as a flexible dose regimen in the Double-Blind Induction Phase.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Duloxetine (Oral Antidepressant)
Description: Duloxetine could be selected as the oral antidepressant medication by the investigator based on review of Massachusetts General Hospital - Antidepressant Treatment Response Questionnaire (MGH-ATRQ) and relevant prior antidepressant medication information. The minimum therapeutic dose is 60 milligram per day (mg/day).

Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: Duloxetine (Oral Antidepressant)
Description: Duloxetine could be selected as the oral antidepressant medication by the investigator based on review of Massachusetts General Hospital - Antidepressant Treatment Response Questionnaire (MGH-ATRQ) and relevant prior antidepressant medication information. The minimum therapeutic dose is 60 milligram per day (mg/day).

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Escitalopram (Oral antidepressant)
Description: Escitalopram could be selected as the oral antidepressant medication by the investigator based on review of MGH-ATRQ and relevant prior antidepressant medication information. Escitalopram will be titrated upto a dose of 20 mg/day, but if not tolerated the dose can be reduced to the minimum therapeutic dose of 10 mg/day.

Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: Escitalopram (Oral antidepressant)
Description: Escitalopram could be selected as the oral antidepressant medication by the investigator based on review of MGH-ATRQ and relevant prior antidepressant medication information. Escitalopram will be titrated upto a dose of 20 mg/day, but if not tolerated the dose can be reduced to the minimum therapeutic dose of 10 mg/day.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Sertraline (Oral Antidepressant)
Description: Sertraline could be selected as the oral antidepressant medication by the investigator based on review of MGH-ATRQ and relevant prior antidepressant medication information. Sertraline will be titrated upto a dose of 150 mg/day, but if not tolerated the dose can be reduced to the minimum therapeutic dose of 50 mg/day.

Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: Sertraline (Oral Antidepressant)
Description: Sertraline could be selected as the oral antidepressant medication by the investigator based on review of MGH-ATRQ and relevant prior antidepressant medication information. Sertraline will be titrated upto a dose of 150 mg/day, but if not tolerated the dose can be reduced to the minimum therapeutic dose of 50 mg/day.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Venlafaxine Extended Release (XR) (Oral Antidepressant)
Description: Venlafaxine Extended Release could be selected as the oral antidepressant medication by the investigator based on review of MGH-ATRQ and relevant prior antidepressant medication information. Venlafaxine Extended Release will be titrated upto a dose of 225 mg/day, but if not tolerated the dose can be reduced to the minimum therapeutic dose of 150 mg/day.

Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: Venlafaxine Extended Release (XR) (Oral Antidepressant)
Description: Venlafaxine Extended Release could be selected as the oral antidepressant medication by the investigator based on review of MGH-ATRQ and relevant prior antidepressant medication information. Venlafaxine Extended Release will be titrated upto a dose of 225 mg/day, but if not tolerated the dose can be reduced to the minimum therapeutic dose of 150 mg/day.