A Clinical Study That Will Evaluate How Well SEP-363856 Works and How Safe it is in People With Schizophrenia That Switch to SEP-363856 From Their Current Antipsychotic Medication

Inclusion Criteria: This list is not all inclusive

• Participants meets Diagnostic and Statistical Manual of Mental Disorders, FifthEdition (DSM-5) criteria for a diagnosis of schizophrenia.

• Participants are judged to be clinically stable (ie, no evidence of an acuteexacerbation of schizophrenia) by the Investigator for at least 8 weeks prior toBaseline.

• Participants must be judged by the Investigator to be an appropriate candidate forswitching current antipsychotic medication due to safety or tolerability concernsand/or insufficient efficacy.

• Participants are taking an oral antipsychotic and the antipsychotic regimen has beenstable for at least 6 weeks prior to Screening.

Exclusion Criteria:This list is not all inclusive

• Participant has a current DSM-5 diagnosis or presence of symptoms consistent with amajor psychiatric disorder, other than schizophrenia, that is the primary focus oftreatment.

• Participants are at significant risk of harming self or others based oninvestigator's judgment.

• Participant has any clinically significant unstable medical condition or anyclinically significant chronic disease that in the opinion of the Investigator,would limit the participant's ability to complete and/or participate in the study.

• Female participant who is pregnant or lactating.

• Participant tests positive for drugs of abuse at Screening.