A Study to Assess the Electrophysiology, Safety, Tolerability, and Pharmacokinetics of SAGE-718 Using a Ketamine Challenge in Healthy Subjects

Inclusion Criteria:

1. Subject has a body weight ≥50 kg and body mass index ≥18.0 and ≤30.0 kg/m2 at
screening.

2. If female, subject is post-menopausal (at least 12 months of spontaneous amenorrhea
with confirmatory follicle stimulating hormone >40 mIU/mL), or surgically sterile
(bilateral tubal ligation, bilateral oophorectomy, and/or hysterectomy).

3. Subject is healthy with no history or evidence of clinically relevant medical
disorders as determined by the Investigator.

Exclusion Criteria:

1. Subject has a history or presence of any psychiatric disease or condition including
suicidal ideation or behavior, has answered YES to any question on the C-SSRS at
screening or admission, or is currently at risk of suicide in the opinion of the
Investigator.

2. Subject has a history or presence of a neurologic disease or condition, including but
not limited to epilepsy, closed head trauma with clinically significant sequelae, or a
prior seizure.

3. Subject has a family history of epilepsy.

4. Subject has obstructed venous access and/or has skin disease, rash, acne, or abrasion
at venous access site that may affect the ability to obtain a PK sample or affect the
ability to receive the ketamine infusions.

5. Subject has had previous exposure to or is known to be allergic to ketamine or any of
its excipients.