54135419SUI3001: A Study to Evaluate the Efficacy and Safety of Intranasal Esketamine in Addition to Comprehensive Standard of Care for the Rapid Reduction of the Symptoms of Major Depressive Disorder, Including Suicidal Ideation, in Adult Participants Assessed to be at Imminent Risk for Suicide

Change From Baseline in Clinical Global Impression of Severity of Suicidality- Revised (CGI-SS-R) Score at 24 Hours After the First Dose (Day 2) (LOCF Data) During Double-blind Phase

CGI-SS-R was derived from the Clinical Global Impression Severity Scale (CGI-S), a global rating scale that gives an overall measure of the severity of a participants illness. The CGI-SS-R rating is scored on a 7-point scale from 0 (normal, not at all suicidal) to 6 (among the most extremely suicidal participants). A higher score indicates a more severe condition and a reduction in score indicates improvement (that is, lower severity of suicidality).

Time frame: Baseline (Day 1, predose) and 24 hours first post dose (Day 2)

Number of Participants Who Achieved Remission (MADRS Total Score Less Than or Equal to [<=] 12) Through the Double-blind Phase

Participants who had a MADRS total score of \<=12 were considered remitters. MADRS is clinician-rated scale designed to measure depression severity, and to detect changes due to antidepressant treatment. Scale consists of 10 items (apparent sadness, reported sadness, inner tension, sleep, appetite, concentration, lassitude, interest level, pessimistic thoughts, and suicidal thoughts), each of which is scored from 0 (item is not present or is normal) to 6 (severe or continuous presence of symptoms), summed for a total possible score of 0 to 60. Higher scores represent more severe condition and a negative change in score indicates improvement.

Time frame: Days 1 (4 hours postdose), 2, 4, 8, 11, 15, 18, 22 and Day 25 (predose and 4 hours postdose)

Change From Baseline in Montgomery Asberg Depression Rating Scale Total Score at Days 1, 2, 4, 8, 11, 15, 18, 22 and 25 During Double-blind Phase

MADRS is clinician-rated scale designed to measure depression severity, and to detect changes due to antidepressant treatment. Scale consists of 10 items (apparent sadness, reported sadness, inner tension, sleep, appetite, concentration, lassitude, interest level, pessimistic thoughts, and suicidal thoughts), each of which is scored from 0 (item is not present or is normal) to 6 (severe or continuous presence of symptoms), summed for a total possible score of 0 to 60. Higher scores represent more severe condition and a negative change in score indicates improvement.

Time frame: Baseline and Days 1, 2, 4, 8, 11, 15, 18, 22 and 25 (predose and 4 hours postdose)

Change From Baseline in Clinical Global Impression- Severity of Suicidality-Revised (CGI-SS-R) at Days 1, 2, 4, 8, 11, 15, 18, 22 and 25 During Double-blind Phase

CGI-SS-R was derived from the Clinical Global Impression Severity Scale (CGI-S), a global rating scale that gives an overall measure of the severity of a participants illness. The CGI-SS-R rating is scored on a 7-point scale from 0 (normal, not at all suicidal) to 6 (among the most extremely suicidal participants). A higher score indicates a more severe condition. Negative change in score indicates improvement.

Time frame: Baseline and Days 1, 2, 4, 8, 11, 15, 18, 22 and 25

Number of Participants Who Achieved Resolution of Suicidality (CGI-SS-R Score of 0 or 1) Through Double-blind Phase

CGI-SS-R was derived from the Clinical Global Impression Severity Scale (CGI-S), a global rating scale that gives an overall measure of the severity of a participants illness. The CGI-SS-R rating is scored on a 7-point scale from 0 (normal, not at all suicidal) to 6 (among the most extremely suicidal participants). A higher score indicates a more severe condition. Negative change in score indicates improvement. A participant was considered to achieve resolution of suicidality at a given time point if the CGI-SS-R score was 0 (normal, not at all suicidal) or 1 (questionably suicidal).

Time frame: Days 1, 2, 4, 8, 11, 15, 18, 22 and 25

Change From Baseline in Clinical Global Impression of Imminent Suicide Risk (CGI-SR-I) Scale Total Score at Days 1, 2, 4, 8, 11, 15, 18, 22 and 25 During Double-blind Phase

The CGI-SR-I is a scale summarizing the clinician's best assessment of the likelihood that the participant will attempt suicide in the next 7 days. The CGI-SR-I rating is scored on a 7-point scale: where' 0 (no imminent suicide risk); 1 (minimal imminent suicide risk), 2 (mild imminent suicide risk), 3 (moderate imminent suicide risk), 4 (marked imminent suicide risk), 5 (severely imminent suicide risk), 6 (extreme imminent suicide risk). Higher score indicates a more severe condition. Negative change in score indicates improvement.

Time frame: Baseline and Days 1, 2, 4, 8, 11, 15, 18, 22 and 25

Change From Baseline in Beck Hopelessness Scale (BHS) Total Score at Days 8 and 25 During Double-blind Phase

BHS is a self-reported measure to assess one's level of negative expectations or pessimism regarding future. It consists of 20 true-false items that examine respondent's attitude over past week by either endorsing a pessimistic statement or denying an optimistic statement; 9 are keyed false and 11 are keyed true. For every statement, each response was assigned score of 0 or 1. Total BHS score is sum of item responses, ranged from 0-20, where higher score represented higher level of hopelessness.

Time frame: Baseline, Days 8 and 25

Change From Baseline in EuroQol-5 Dimension-5 Level (EQ-5D-5L) at Days 2, 11 and 25 During Double-blind Phase: Health Status Index

EQ-5D-5L measures health outcome. It consists of EQ-5D-5L descriptive system and EQ visual analogue scale (EQ-VAS). EQ-5D-5L system comprises following 5 dimensions: mobility, self-care, usual activities, pain/discomfort and anxiety/depression. Each of 5 dimensions is divided into 5 levels of perceived problems (Level 1-no problem, Level 2-slight problems, Level 3-moderate problems, Level 4-severe problems, Level 5-extreme problems). Participant selects answer for each of 5 dimensions considering response that best matches his/her health "today". Responses were used to generate a health status index (HSI). Health Status Index ranges from 0.148 - 0.949, anchored at 0 (dead) and 1 (full health). Positive change in score indicates improvement.

Time frame: Baseline and Days 2, 11 and 25

Change From Baseline in EuroQol-5 Dimension-5 Level (EQ-5D-5L) at Days 2, 11 and 25 During Double-blind Phase: EQ-Visual Analogue Scale (EQ-VAS)

EQ-5D-5L measures health outcome. It consists of EQ-5D-5L descriptive system and the EQ visual analogue scale (EQ-VAS). EQ-VAS score from 0 (worst health) to 100 (best health), positive change in score indicates improvement.

Time frame: Baseline, Days 2, 11 and 25

Change From Baseline in EuroQol-5 Dimension-5 Level (EQ-5D-5L) at Days 2, 11 and 25 During Double-blind Phase: Sum Score

EQ-5D-5L measures health outcome. It consists of EQ-5D-5L system and EQ-VAS. EQ-5D-5L system comprises following 5 dimensions: mobility, self-care, usual activities, pain/discomfort and anxiety/depression. Each of 5 dimensions is divided into 5 levels of perceived problems (Level 1-no problem, Level 2-slight problems, Level 3-moderate problems, Level 4-severe problems, and Level 5-extreme problems). Participant selects answer for each of 5 dimensions considering response that best matches his/her health "today". Responses were used to generate a health status index (HSI). Health Status Index ranges from 0.148 - 0.949, anchored at 0 (dead) and 1 (full health), a lower score indicates worse health. Sum score=(sum of the scores from the 5 dimensions minus 5)\*5. Sum score ranges from 0-100. Higher score indicates a more severe problem. Negative change in score indicates improvement.

Time frame: Baseline, Days 2, 11 and 25

Change From Baseline in Quality of Life in Depression Scale (QLDS) Total Score at Days 2, 11 and 25 During Double-blind Phase

The QLDS is a disease specific patient-reported outcome designed to assess health related quality of life in participants with major depressive disorder (MDD). The instrument has a recall period of "at the moment", contains 34-items with "true"/"not true" response options and takes approximately 5-10 minutes to complete. The total score range is from 0 (good quality of life) to 34 (very poor quality of life). A higher score indicates a more severe condition. Negative change indicates improvement.

Time frame: Baseline and Days 2, 11 and 25

Treatment Satisfaction Questionnaire for Medication (TSQM-9) Total Score at Days 15 and 25 During Double-blind Phase

The TSQM-9 is a 9-item generic patient-reported outcome instrument to assess participants' satisfaction with medication. It covers domains of effectiveness, convenience, and global satisfaction. The TSQM-9 domain scores were calculated as recommended by the instrument authors. (i) Effectiveness = \[(item 1 + item 2 + item 3) - 3\]/18\*100, (ii) Convenience = \[(item 4 + item 5 + item 6) - 3\]/18\*100 and (iii) Global satisfaction = \[(item 7 + item 8 + item 9) - 3\]/14\*100. Each domain score can be calculated only if all the three items considered in the calculation of that score are not missing. The TSQM-9 domain score ranges from 0 to 100, with higher scores representing higher satisfaction.

Time frame: Days 15 and 25

Change From Baseline in Suicide Ideation and Behavior Assessment Tool (SIBAT) Module 5 (My Risk) Question 3 (Patient-reported FoST) Total Score at Days 1, 2, 4, 8, 11, 15, 18, 22 and 25 During Double-blind Phase

SIBAT is an assessment tool that captures suicidal ideation, behavior, and risk. It permits assessment of change in suicidal ideation and behavior and documents clinician assessment of severity of suicidality and suicide risk. SIBAT is organized into 8 modules divided into 2 major divisions: patient-reported section (Modules 1-5) and clinician-rated section (Modules 6-8). Patient-reported section has modules of demographics and suicide history, risk/protective factors, suicidal thinking, suicide behavior, and suicide risk. Question 3 from Module 5 asks participants to describe their thinking about suicide right now from 5 response options ranging from 0 (I have no suicidal thoughts) to 4 (I have suicidal thoughts all of time). SIBAT Module 5 (My Risk) Question 3 (Patient-reported FoST) total score ranges from 0 to 4; a higher score indicates a more severe condition. Negative change in score indicates improvement.

Time frame: Baseline, Days 1, 2, 4, 8, 11, 15, 18, 22 and 25

Change From Baseline in Suicide Ideation and Behavior Assessment Tool (SIBAT) Module 7 - Clinician-rated FoST Total Score at Days 1, 2, 4, 8, 11, 15, 18, 22 and 25 During Double-blind Phase

SIBAT is assessment tool that captures suicidal ideation, behavior, and risk. It permits assessment of change in suicidal ideation and behavior and documents clinician assessment of severity of suicidality and suicide risk. SIBAT has 8 modules divided into 2 major divisions: patient-reported section (Modules 1-5) and clinician-rated section (Modules 6-8). Clinician-rated section has modules for semi-structured interview, clinical global impressions of current severity of suicidality and imminent suicide risk, clinical global impression of long-term suicide risk, and clinical judgment of optimal suicide management. The score anchor point as in participant report frequency of suicidal thinking (FoST) that is, response options from never to all the time. Module 7-FoST score ranges from 0-5; higher score indicates more severe condition. Negative change in score indicates improvement.

Time frame: Baseline and Days 1, 2, 4, 8, 11, 15, 18, 22 and 25

Number of Participants With Treatment Emergent Adverse Events (TEAEs): DB Treatment Phase

An adverse event (AE) is any untoward medical occurrence in a clinical study participant administered a medicinal (investigational or non-investigational) product. An AE does not necessarily have a causal relationship with the treatment. An adverse event can therefore be any unfavorable and unintended sign (including an abnormal finding), symptom, or disease temporally associated with the use of a medicinal (investigational or non investigational) product, whether or not related to that medicinal (investigational or non-investigational) product. A TEAE is categorized as related if assessed by the investigator as possibly, probably, or very likely related to study agent.

Time frame: Up to Day 25

Number of Participants With Treatment Emergent Abnormal Laboratory Values: DB Treatment Phase

Low/high abnormal values are: Alanine aminotransferase (ALT)-high=200 Units per liter(U/L); ALP-high=250U/L; aspartate aminotransferase(AST)-high=250U/L; gamma glutamyl transferase(GGT)=300U/L; Albumin(low=24g/L,high=60 g/L); Bicarbonate(low=15.1, high=34.9mmol/L); Bilirubin(high=51.3micromol/L); calcium(low=1.5,high=3mmol/L);Chloride(low=94,high=112mmol/L); CK(High=990U/L); Creatinine(High=265.2micromol/L); Eosinophils(High=10%); Erythrocytes(low=3.0\*1012/L,high=6.4\*1012/L); Glucose(low=2.2,high=16.7mmol/L); Hemoglobin(low=80g/L,high=190g/L);Hematocrit(low=0.28, high=0.55 fraction); LD(high=500U/L); Leukocytes(low=2.5\*109/L,high=15.5\*109/L); Lymphocytes(low=10%,high=60%); Monocytes(high=20%); Neutrophils(low=30%,high=90%); Phosphate(low=0.7 mmol/L,high=2.6mmol/L); Platelet count(low=100\*109/L,high=600\*109/L\]; Potassium(low=3.0mmol/L,high=5.8 mmol/L\]; Protein(low=50 g/L); Sodium(low=125 mmol/L,high=155 mmol/L); Urate(low=89.2 micromol/L,high=594.8micromol/L); Urine(high=8.0 pH).

Time frame: Up to Day 25

Number of Participants With Abnormal Nasal Examinations at Day 25: DB Treatment Phase

Number of participants with abnormal nasal examination were reported. Nasal examination of visual inspection of the epistaxis, nasal crusts, nasal discharge, and nasal erythema was performed.

Time frame: At Day 25

Number of Participants With Treatment Emergent Abnormal Electrocardiogram (ECG) Values at Any Time: DB Treatment Phase

Number of participants with treatment emergent abnormal ECG values for variables including heart rate (abnormally low refers to less than or equal to \[\<=\] 50 beats per minute \[bpm\] , abnormally high refers greater than or equal to \[\>=\] 100 bpm), pulse rate (PR) interval (abnormally high refers to \>= 210 milliseconds \[msec\]), QRS interval (abnormally Low refers to \<= 50, abnormally high refers to \>= 120 msec) and QT interval (abnormally low refers to \<= 200, abnormally high \>= 500 msec) were reported.

Time frame: Up to Day 25

Number of Participants With Abnormal Arterial Oxygen Saturation (SpO2) Levels (Less Than [<] 93%) as Assessed by Pulse Oximetry at Any Time: DB Treatment Phase

Pulse oximetry was used to measure arterial SpO2 levels. On each dosing day, the device was attached to the finger, toe, or ear, and SpO2 was monitored and documented. If oxygen saturation levels were less than (\<) 93% at any time during the 1.5 hours postdose interval, pulse oximetry was recorded every 5 minutes until levels return to \>= 93% or until the participant is referred for appropriate medical care, if clinically indicated. Participants with at least 2 consecutive postdose oxygen saturation below 93% during the DB treatment phase were reported.

Time frame: Up to Day 25

Number of Participants With Treatment Emergent Vital Signs Abnormalities: DB Treatment Phase

Number of participants with treatment emergent vital signs abnormalities (pulse rate in bpm \[abnormally low = a decrease from baseline of \>= 15 to a value \<= 50; abnormally high = an increase from baseline of \>=15 to a value \>=100\] , systolic blood pressure \[SBP\] in mmHg \[abnormally low = a decrease from baseline of \>= 20 to a value \<= 90; abnormally high = an increase from baseline of \>= 20 to a value \>= 180\], and diastolic blood pressure \[DBP\] in mmHg \[abnormally low= a decrease from baseline of \>=15 to a value \<= 50; abnormally high = an increase from baseline of \>= 15 to a value \>= 105) were reported.

Time frame: Up to Day 25

Number of Sedated Participants as Assessed by Modified Observer's Assessment of Alertness/Sedation (MOAA/S) Score at Any Time: DB Treatment Phase

MOAA/S was used to measure treatment-emergent sedation with correlation to levels of sedation defined by the American society of anesthesiologists (ASA) continuum. The MOAA/S scores range from 0 to 5 where,0 = no response to painful stimulus; ASA continuum = general anesthesia, 1 = responds to trapezius squeeze; ASA continuum = deep sedation, 2 = purposeful response to mild prodding or mild shaking; ASA continuum = moderate sedation, 3 = responds after name called loudly or repeatedly; ASA continuum = moderate sedation, 4 = lethargic response to name spoken in normal tone; ASA continuum = moderate sedation and 5 = readily responds to name spoken in normal tone (awake); ASA continuum = minimal sedation.

Time frame: Up to Day 25

Number of Participants With an Increase in Clinician-administered Dissociative States Scale (CADSS) Total Score Over Time: DB Treatment Phase

The CADSS used to measure present-state dissociative symptoms, and to assess treatment-emergent dissociative symptoms. It comprises 23 subjective items divided into 3 components: depersonalization (with score range from 0 to 28), derealization (with score range from 0 to 52), and amnesia (with score range from 0 to 8). Participants responses are coded on a 5-point scale (0 = "Not at all", 1 = "Mild", 2 = "Moderate", 3 = 'Severe" and 4 = "Extreme"). The total score is sum of the 23 items and range from 0 to 92, where 0 (best) and 92 (worst). A higher score indicates a more severe condition. Number of participants with an increase in CADSS total score (increase based on maximum CADSS total score change from predose of \> 0) was reported.

Time frame: Days 1, 4, 8, 11, 15, 18, 22 and 25