This study is testing a new medicine called NMRA-335140 for people with Major Depressive Disorder (MDD). MDD is a condition when someone feels very sad, hopeless, or loses interest in things they usually enjoy for a long period. This study will compare the effects of NMRA-335140 with a placebo. A placebo looks like medicine but doesn't have any active ingredients. The study is randomized (participants are chosen by chance), double-blind (neither doctors nor participants know who gets the real medicine), and placebo-controlled (some get the real medicine, some get the placebo).
The study has two parts: a Screening Period of up to 28 days to check if you qualify and a 6-week Treatment Period. During the Treatment Period, you will receive either NMRA-335140 or placebo. If you complete the study and meet certain conditions, you might be able to join an extension study for more treatment.
- Duration: Screening (up to 28 days) + 6-week Treatment Period.
- Visits: Regular check-ins with the study team.
- Potential Risks: Some participants may receive a placebo instead of the actual medication.