A Study to Evaluate Safety and Efficacy of SAGE-547 in Participants With Moderate Postpartum Depression (547-PPD-202C)

Key Inclusion Criteria: * Participant either must have ceased lactating at screening; or if still lactating or actively breastfeeding at screening, agreed to temporarily cease giving breastmilk to their infant(s). * Participant had a major depressive episode that began no earlier than the third trimester and no later than the first 4 weeks following delivery, as diagnosed by Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I). * Participant had a HAM-D total score of ≥20 and ≤25 at screening and Day 1 (prior to dosing). * Participant was ≤ six months postpartum. * Participant was amenable to intravenous therapy. Key Exclusion Criteria: * Active psychosis. * Attempted suicide associated with index case of postpartum depression. * Medical history of bipolar disorder. Note: Other protocol-defined inclusion/exclusion criteria applied.