North Bay Village

Researchers are evaluating the effect of seltorexant as an add-on treatment to antidepressants in adults and elderly people with major depressive disorder who also have insomnia symptoms and have not responded well to their current antidepressant therapy with SSRIs or SNRIs. This Phase 3 study aims to understand how well seltorexant works, its safety, and its ability to maintain improvement compared with a placebo. Participants in part 1 of the study will receive either seltorexant or a matching placebo once daily for 6 weeks, alongside their usual SSRI or SNRI antidepressant. Those who complete part 1 and meet criteria for part 2, plus new participants entering directly into part 2, will receive seltorexant during an open-label induction and stabilization phase. Participants who respond well will then enter a double-blind maintenance phase, receiving either seltorexant or placebo daily, continuing their baseline antidepressant throughout. During the study, participants will be monitored through rating scales measuring depression severity, sleep disturbance, and patient health questionnaires at baseline and specified days up to two years and ten months. Researchers will assess changes in depression symptoms and time to relapse, along with safety and tolerability. Participants will be followed through treatment phases and post-treatment periods to evaluate the maintenance of effects and overall safety.