Study to Evaluate Efficacy and Safety of 20 mg Seltorexant as Add-On Treatment in Adults and Elderly With Major Depressive Disorder and Insomnia Symptoms

What this Trial Is About

Researchers are evaluating how well seltorexant works and its safety when used alongside antidepressants in adults and elderly people with major depressive disorder and insomnia symptoms. This study focuses on participants who have not had adequate improvement from their current antidepressant treatment with selective serotonin reuptake inhibitors SSRIs or serotonin-norepinephrine reuptake inhibitors SNRIs. The trial aims to understand both the initial effects and the longer-term maintenance of seltorexant compared to placebo in this population. Participants in the study will receive either seltorexant or a matching placebo orally once daily for six weeks during the first double-blind treatment phase, while continuing their baseline SSRI or SNRI antidepressant. Those who complete Part 1 and meet criteria will enter Part 2, which includes an open-label phase where all receive seltorexant alongside their antidepressant. Participants achieving stable response may then continue with seltorexant or placebo during the double-blind maintenance phase. Throughout, all continue their original antidepressant treatment. During the study, participants will undergo assessments including depression rating scales such as the Montgomery-Asberg Depression Rating Scale MADRS and sleep disturbance questionnaires like the PROMIS-SD. The main outcomes include changes in depression scores after 43 days and time to relapse during maintenance, which may last up to nearly three years. Safety and tolerability will be closely monitored, and participants who do not continue to Part 2 will have a post-treatment follow-up after Part 1. Total participation may extend over several months or years depending on the study phase.

Phase 3 Study of Adjunctive Treatment With Seltorexant in Adult and Elderly Participants With Major Depressive Disorder and Insomnia Symptoms