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

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

The purpose of this study is to evaluate the efficacy of intranasal esketamine 84 milligram (mg) compared with intranasal placebo along with standard care treatment, in reducing the symptoms of major depressive disorder (MDD) (an affective disorder manifested by either a dysphoric mood or loss of interest or pleasure in usual activities, the mood disturbance is prominent and relatively persistent), including the risk for suicide as assessed by the Investigator, in participants who will be assessed to be at imminent risk for suicide.

This is a randomized (study medication assigned to participants by chance), double-blind (neither physician nor participant knows assigned study treatment), placebo-controlled (participants are randomly assigned to a test treatment or to an identical-appearing treatment that does not contain the test drug), and multicenter (when more than one hospital or medical school team works on a medical research study), study of esketamine in participants with major depressive disorder (MDD) in participants who will be assessed to be at imminent risk for suicide, as measured by the change from Baseline on the Montgomery-Asberg Depression Rating Scale (MADRS) total score at 4 hours postdose on Day 1. The duration of study will be approximately 81 days per participant. The study consists of 3 parts: Screening (that is, with in 1 day before study commences on Day 1) and double-blind Treatment (from Day 1-25) and Follow-up (from Day 26 up to Day 81). All the eligible participants will be provided standard care treatment and will be randomly assigned to either esketmaine or placebo treatment. Esketamine/placebo will be administered by intranasal route (delivery of medications through the nasal mucosa) two times per week for 4 weeks. Efficacy of the participants will be primarily evaluated through MADRS. Participants' safety will be monitored throughout the study.

Inclusion Criteria:

• Participants must meet Diagnostic and Statistical Manual of Mental Disorders, fourth edition (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 psychiatric hospitalization due to imminent risk of suicide
• Participant has a Montgomery Asberg Depression Rating Scale (MADRS) total score of greater than or equal to (>=) 22 predose on Day 1
• As part of standard of care treatment, participant agrees to be hospitalized voluntarily for a recommended period of 5 days after randomization (that is, through Day 5), and take prescribed non-investigational antidepressant therapy(ies) for at least 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, borderline personality disorder, antisocial personality disorder, histrionic personality disorder, and narcissistic personality disorder)
• Participant meets DSM-IV criteria for borderline personality disorder, based on clinical interview
• Participant has a current or prior diagnosis of a psychotic disorder, major depressive disorder (MDD) with psychosis, or obsessive compulsive disorder
• Participant with a history or current signs and symptoms of liver or renal insufficiency; 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) despite diet, exercise or a stable dose of an allowed anti-hypertensive treatment at Screening; or any past history of hypertensive crisis