Study to Assess the Effects of Oral NMRA-335140 in Participants With Major Depressive Disorder

This randomized, double-blind, placebo-controlled, multicenter study will evaluate the effects of NMRA-335140 (formerly BTRX-335140) on symptoms of depression in participants with Major Depressive Disorder (MDD). The study design consists of a Screening Period (up to 35 days), and a 6-week Treatment Period (during which participants will receive either NMRA-335140 or placebo). At the completion of the 6-week Treatment Period, participants who complete the study, provide informed consent, and meet the eligibility criteria may enter an open-label extension study (NMRA-335140-501).