A Study of the Long-term Safety and Tolerability of an Investigational Drug in People With Schizophrenia.

This is a 52-week, multicenter, randomized, double-blind, parallel-group, flexible-dose study designed to evaluate the long-term safety and tolerability of SEP-363856 (50 to 100 mg/day) compared with quetiapine XR (400 to 800 mg/day) in clinically stable adult participants with schizophrenia. This study is projected to randomize a least 300 participants to two treatment groups (SEP-363856 50 to 100 mg/day or quetiapine XR 400 to 800 mg/day) in a 2:1 ratio. Study drug will be taken once a day and may be taken without food or with a light meal. Sumitomo Pharma America Inc. was the former Sponsor and conducted this study. Sumitomo was responsible for analysis and clinical study report (CSR) completion. Otsuka took over study after IND was transferred and is concluding activities with registry postings.