Safety, Tolerability, and Pharmacokinetics of Lumateperone in Pediatric Patients With Schizophrenia or Schizoaffective Disorder

Main Inclusion Criteria: * Male or female patients between 13 and 17 years of age, inclusive * Clinical diagnosis of schizophrenia or schizoaffective disorder according to Diagnostic and Statistical Manual of Mental Disorders (DSM-5) * Free from acute exacerbation of their psychosis for at least 3 months prior to Screening * Clinical Global Impression - Severity (CGI-S) score ≤ 4 * Body mass index (BMI) within 2 standard deviations of, age- and gender-specific body measurements (based on CDC Clinical Growth Chart, 2000) * Ability to swallow capsules Main Exclusion Criteria: * Has a primary psychiatric diagnosis other than schizophrenia or schizoaffective disorder * Reports having experienced suicidal ideation within 6 months prior to Screening, any suicidal behavior within 2 years prior to Screening based on the Columbia-Suicide Severity Rating Scale (C-SSRS), and/or the investigator assesses the patient to be a safety risk to him/herself or others * Clinically significant abnormality within 2 years of Screening that in the Investigator's opinion may place the patient at risk or interfere with study outcome variables * History of a clinically significant cardiac disorder and/or abnormal screening electrocardiogram (ECG) or a QT interval corrected for heart rate using Fridericia formula \> 450 msec in males or \> 470 msec in females