Introduction
depressive disorder, human abuse, MDD, disability, chronic disease
CHRONIC DISEASE
Major depressive disorder (MDD) is the second leading cause of disability and chronic disease burden in the United States, among all medical conditions [Esmethadone (REL-1017) is the opioid-inactive dextro-isomer of methadone and a low affinity, low potency uncompetitive NMDAR antagonist [Phase 1 and Phase 2 results with esmethadone provided safety, tolerability, and pharmacokinetic (PK) results across a range of doses sufficient to inform the design and conduct of the human abuse potential (HAP) studies [