Please select the eligibility criteria that correspond to the clinical trial below.
Title: A Randomized, Double-blind, Multicenter, Active-controlled Study to Evaluate the Efficacy, Safety, and Tolerability of Flexible Doses of Intranasal Esketamine Plus an Oral Antidepressant in Adult Subjects With Treatment-resistant Depression
Brief Summary: The purpose of this study is to compare the efficacy and safety of switching treatment-resistant depression (TRD) subjects from a prior antidepressant treatment (to which they have not responded) to either intranasal esketamine plus a new oral antidepressant or switching to a new oral antidepressant plus intranasal placebo.


Options:
A: Inclusion Criteria:

* Aged 18-55 years
* Fulfilled the DSM-IV criteria of major depressive disorder
* Had a 17-item Hamilton Rating Scale for Depression (HAMD-17)\>or= 18
* No DSM-IV diagnosis of substance abuse or dependence (including alcohol) within the past 6 months
* Had been drug free for \> 3 months
* Physically healthy and had all laboratory parameters within normal limits.
* Agree to participate in the study and provide informed consent

Exclusion Criteria:

* Had history of epilepsy, head trauma or other major neurological or medical diseases
* Had psychotic depression, bipolar I/II disorder, schizophrenia or any other psychotic disorder
* Moderate-severe suicidal risks
* Severe cognitive impairment
* Female subjects who were pregnant, or at risk of pregnancy or lactation
* Initiating or stopping formal psychotherapy within six weeks prior to enrollment
* Had a history of poor response to SSRIs or previously received electroconvulsive therapy
* Had a history of severe adverse reaction to SSRIs.
B: Inclusion Criteria:

1. Male or female patients, 21-65 years;
2. Women of childbearing potential must agree to use a medically accepted means of contraception for the duration of the study;
3. Primary diagnosis of major depressive disorder as assessed by the SCID-P;
4. Current depressive episode;
5. History of a failure to respond to at least one (1) adequate pharmacotherapy trials in the current major depressive episode;
6. Subjects must have scored ≥ 30 on the IDS-C30 at Screening ≥ 24 at Treatment Day #1 and #2;
7. Each subject must have a level of understanding sufficient to agree to all tests and examinations required by the protocol and must sign an informed consent document;
8. Subjects must be able to identify a family member, physician, or friend who will participate in the Treatment Contract and serve as an emergency contact.

Exclusion Criteria:

1. Women who plan to become pregnant, are pregnant or are breast-feeding;
2. Any unstable medical illness including hepatic, renal, gastroenterologic, respiratory, cardiovascular, endocrinologic, neurologic, immunologic, or hematologic disease;
3. Clinically significant abnormal findings of laboratory parameters, physical examination, or ECG;
4. Lifetime history of schizophrenia, schizoaffective disorder, bipolar disorder, OCD, mental retardation, pervasive developmental disorders, or Tourette's syndrome;
5. Drug or alcohol abuse or dependence within the preceding 6 months;
6. Lifetime abuse or dependence on ketamine or phencyclidine;
7. Patients judged by study investigator to be at high risk for suicide.
8. Previous participation in a ketamine study at Mount Sinai
C: Inclusion Criteria:

* At the time of signing the informed consent form (ICF), participant must be a man or woman 18 (or older if the minimum legal age of consent in the country in which the study is taking place is greater than \[\>\]18) to 64 years of age, inclusive
* At the start of the screening/prospective observational phase, participant must meet the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) diagnostic criteria for single-episode major depressive disorder (MDD) (if single-episode MDD, the duration must be greater than or equal to \[\>=\] 2 years) or recurrent MDD, without psychotic features, based upon clinical assessment and confirmed by the Mini-International Neuropsychiatric Interview (MINI)
* At the start of the screening/prospective observational phase, participant must have an Inventory of Depressive Symptomatology-Clinician rated ( IDS-C30) total score of greater than or equal to (\>=) 34
* At the start of the screening/prospective observational phase, participant must have had non-response (greater than or equal to \[\<=25\] percent \[%\] improvement) to ≥1 but less than or equal to (\<=) 5 (if current episode is \>2 years, upper limit is applicable to only the last 2 years) oral antidepressant treatments in the current episode of depression, assessed using the Massachusetts General Hospital - Antidepressant Treatment Response Questionnaire (MGH-ATRQ) and documented by medical history and pharmacy/prescription records, for the current episode of depression. In addition, the participant is taking a different oral antidepressant treatment (on the MGH-ATRQ) for at least the previous 2 weeks at or above the minimum therapeutic dose
* The participant's current major depressive episode, depression symptom severity (Week 1 MADRS total score \>=28 required), and antidepressant treatment response in the current depressive episode, must be confirmed using a Site Independent Qualification Assessment

Exclusion Criteria:

* Participants who have previously demonstrated nonresponse of depressive symptoms to esketamine or ketamine in the current major depressive episode, to all 4 of the oral antidepressant treatment options available for the double-blind induction phase (ie, duloxetine, escitalopram, sertraline, and venlafaxine extended release \[XR\]) in the current major depressive episode (based on MGH-ATRQ), or an adequate course of treatment with electroconvulsive therapy (ECT) in the current major depressive episode, defined as at least 7 treatments with unilateral/bilateral ECT
* Participant has received vagal nerve stimulation (VNS) or has received deep brain stimulation (DBS) in the current episode of depression
* Participant has a current or prior DSM-5 diagnosis of a psychotic disorder or MDD with psychosis, bipolar or related disorders (confirmed by the MINI), comorbid obsessive compulsive disorder, intellectual disability (DSM-5 diagnostic codes 317, 318.0, 318.1, 318.2, 315.8, and 319), borderline personality disorder, antisocial personality disorder, histrionic personality disorder, or narcissistic personality disorder
* Participant has homicidal ideation/intent, per the investigator's clinical judgment, or has suicidal ideation with some intent to act within 6 months prior to the start of the screening/prospective observational phase, per the investigator's clinical judgment or based on the Columbia Suicide Severity Rating Scale (C-SSRS)
* Participants with history of moderate or severe substance or alcohol use disorder according to DSM-5 criteria
D: Inclusion Criteria:

* Patients with a diagnosis of Major Depressive Disorder, currently depressed without psychotic features
* Females must be of non-childbearing potential.

Exclusion Criteria:

* Treatment with Clozapine or ECT within 3 months prior to study
* Current or past history of psychotic features or a diagnosis of schizophrenia or any other psychotic disorder as defined in the DSM-IV

Answer: C