A Study of Seltorexant as Adjunctive Therapy to Antidepressants in Adult and Elderly Participants With Major Depressive Disorder With Insomnia Symptoms Who Have Responded Inadequately to Antidepressant and Long-term Safety Extension Treatment With Seltorexant

Major depressive disorder (MDD) is a common, serious, recurrent disorder. Seltorexant (JNJ-42847922) is a potent and selective antagonist of the human orexin-2 receptor (OX2R) that is being developed for adjunctive treatment of major depressive disorder with insomnia symptoms (MDDIS). The hypothesis for this study is that adjunctive treatment with seltorexant is superior to placebo in treating depressive symptoms, as measured by change in Montgomery Asberg Depression Rating Scale (MADRS) total score from baseline to Day 43 in adult and elderly participants with MDDIS who have had an inadequate response to treatment with a SSRI/SNRI. The study will be conducted in 4 phases: a screening phase (up to 30 days), a double-blind (DB) treatment phase (43 days), open label (OL) treatment phase (1-year), and a post treatment follow-up phase (7 to 14 days after end of treatment). The total study duration for each participant will be up to 64 weeks. Efficacy, safety, pharmacokinetics, and biomarkers will be assessed at specified time points during this study.