A Long-term, Safety and Efficacy Study of Intranasal Esketamine in Treatment-resistant Depression

Inclusion Criteria:

A). For Direct-Entry Participants

* 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)
* At the start of the screening 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 screening, participant must have a MADRS total score of \>=22
* At the start of the screening phase, participants must have had nonresponse to \>=2 oral antidepressant treatments in the current episode of depression, as assessed using the the MGHATRQ and confirmed by documented records (example medical/pharmacy/prescription records or a letter from treating a physician, etc,) B). For Transferred-entry Participants
* All participants who completed the double-blind induction phase of ESKETINTRD3005 study, regardless of their response status, will be eligible to participate in this study, if they meet the study specific eligibility criteria

Exclusion Criteria:

A). For Direct-Entry Participants

* Participant's depressive symptoms have previously not responded to: Esketamine or ketamine in the current major depressive episode per clinical judgment or All of the 4 oral antidepressant treatment options available in the respective country for the open-label induction phase (that is, duloxetine, escitalopram, sertraline, and venlafaxine XR) in the current major depressive episode (based on Massachusetts General Hospital - Antidepressant Treatment Response Questionnaire \[ MGH-ATRQ\])
* Participant has a current or prior DSM-5 diagnosis of a psychotic disorder or MDD with psychotic features, bipolar or related disorders (confirmed by the MINI), obsessive compulsive disorder (current only), intellectual disability (DSM-5 diagnostic codes 317, 318.0, 318.1, 318.2, 315.8, and 319), autism spectrum disorder, 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 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
* Participants who has a Mini Mental State Examination (MMSE) \<25; Has neurodegenerative disorder (example, Alzheimer's disease, vascular dementia, Parkinson's disease), or evidence of mild cognitive impairment (MCI) B). Transferred-Entry Participants
* Participant has taken any prohibited therapies that would not permit dosing on Day 1