A Study to Evaluate SAGE-217 in Adult Subjects With Major Depressive Disorder

Inclusion Criteria:

1. Subject has a diagnosis of MDD as diagnosed by SCID-5-CT, with symptoms that have been
present for at least a 4-week period.

2. Subject is in good physical health and has no clinically significant findings, as
determined by the Investigator, on physical examination, 12-lead ECG, or clinical
laboratory tests.

Exclusion Criteria:

1. Subject has attempted suicide associated with the current episode of MDD.

2. Subject has a medical history of bipolar disorder, schizophrenia, and/or
schizoaffective disorder.

3. Subject has had vagus nerve stimulation, electroconvulsive therapy, or has taken
ketamine within the current major depressive episode.