A Clinical Study to Learn if SEP-363856 Has Physical Dependence in Adults With Schizophrenia

This is a double-blind, placebo-controlled, randomized withdrawal study comparing abrupt discontinuation of SEP-363856 (SEP-363856 switched to placebo) to continuous SEP-363856 treatment in male and female adult subjects with schizophrenia.

Inclusion criteria

(this list is not all inclusive)

• Male or female subject between 18 and 65 years of age (inclusive) at the time of informed consent.
• Subject meets Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria for a primary diagnosis of schizophrenia as established by clinical interview (using the DSM-5 as a reference and confirmed using the Structured Clinical Interview for DSM-5, Clinical Trials Version [SCID-CT]).
• Subject must have a Clinical Global Impression-Severity Scale (CGI-S) score ≤ 4 (normal to moderately ill) at Screening and Day 1.
• Subject must have a PANSS total score ≤ 80 at Screening and a score of ≤ 4 on the following PANSS items at Screening: P7 (hostility) and G8 (uncooperativeness).
• Subject has been taking an antipsychotic for at least 6 weeks prior to Screening and has had no change in antipsychotic medication(s) (minor dose adjustments for tolerability purposes may be permitted) for at least 6 weeks prior to Screening.

Exclusion criteria

(this list is not all inclusive)

• Subject has a DSM-5 diagnosis or presence of symptoms consistent with a current DSM-5 diagnosis other than schizophrenia.
• Subject has attempted suicide within 6 months prior to Screening.
• Subject answers "yes" to "Suicidal Ideation" Item 4 (active suicidal ideation with some intent to act, without specific plan) or Item 5 (active suicidal ideation with specific plan and intent) on the Columbia Suicide Severity Rating Scale (C-SSRS) at Screening (ie, in the past 1 month) or at any subsequent C-SSRS assessment prior to dosing (ie, since last visit).
• Subject is at significant risk of harming him/herself or others (passive or active) according to the Investigator's judgment.