A Double-blind Study to Assess the Efficacy and Safety of Intranasal Esketamine for the Rapid Reduction of the Symptoms of Major Depressive Disorder, Including Suicidal Ideation, in Participants Who Are Assessed to be at Imminent Risk for Suicide

Inclusion Criteria:

• Participants must meet Diagnostic and Statistical Manual of Mental Disorders, fourthedition (DSM-IV) diagnostic criteria for major depressive disorder

• Participants must have current suicidal ideation with intent

• In the Investigator's opinion, participant must be in need of acute psychiatrichospitalization due to imminent risk of suicide

• Participant has a Montgomery Asberg Depression Rating Scale (MADRS) total score ofgreater than or equal to (>=) 22 predose on Day 1

• As part of standard of care treatment, participant agrees to be hospitalizedvoluntarily for a recommended period of 5 days after randomization (that is, throughDay 5), and take prescribed non-investigational antidepressant therapy(ies) for atleast the duration of the double-blind treatment phase (Day 25)

Exclusion Criteria:

• Participant has a current clinical diagnosis of bipolar or related disorders,intellectual disability, or cluster b personality disorder (example, borderlinepersonality disorder, antisocial personality disorder, histrionic personalitydisorder, and narcissistic personality disorder)

• Participant meets DSM-IV criteria for borderline personality disorder, based onclinical interview

• Participant has a current or prior diagnosis of a psychotic disorder, majordepressive disorder (MDD) with psychosis, or obsessive compulsive disorder

• Participant with a history or current signs and symptoms of liver or renalinsufficiency; significant cardiac, vascular, pulmonary, gastrointestinal,endocrine, neurologic, hematologic, rheumatologic, or metabolic disturbances

• Participant has uncontrolled hypertension (systolic blood pressure greater than [>] 160 millimeter of mercury [mmHg] or diastolic blood pressure > 90 mmHg) despitediet, exercise or a stable dose of an allowed anti-hypertensive treatment atScreening; or any past history of hypertensive crisis