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