Janssen Research & Development, LLC
The purpose of this study is to evaluate how well JNJ-54135419 works (efficacy) in addition to comprehensive standard of care (SoC) in rapidly reducing the symptoms of major depressive disorder (MDD, a mental disorder characterized by a persistent feeling of sadness and loss of interest in activities) as compared with psychoactive placebo (does not contain JNJ-54135419) plus SoC in adolescent participants with acute suicidal ideation or behavior.
Inclusion Criteria: * Must meet diagnostic and statistical manual of mental disorders (5th edition) (DSM-5) diagnostic criteria for major depressive disorder (MDD) based upon clinical assessment and confirmed by the mini-international neuropsychiatric interview for children and adolescents (MINI-KID) * Must have a clinical global impression - severity of suicidality - revised (CGI-SS-R) score of "Markedly" or greater (that is, greater than or equal to \[\>=\] 4) at both screening and baseline (predose) visits * Must have a children's depression rating scale - revised (CDRS-R) total score \>=…
Esketamine will be administered as intranasal solution.
Midazolam will be administered as oral solution.
Placebo will be administered as oral solution.
Intranasal placebo will be administered as nasal solution.