The aim of this study is to evaluate the long-term safety and tolerability of lurasidone in the treatment of schizophrenia. Clinically stable adult outpatients with schizophrenia were randomized in a 2 : 1 ratio to 12 months of double-blind treatment with once-daily, flexibly-dosed lurasidone (40–120 mg) or risperidone (2–6 mg). Outcome measures included adverse events (AEs), vital signs, ECG, and laboratory tests. Secondary assessments included measures of psychopathology. A total of 427 patients were randomized to treatment with lurasidone and 202 with risperidone. The three most frequent AEs in the lurasidone group (vs. risperidone) were nausea (16.7 vs. 10.9%), insomnia (15.8 vs. 13.4%), and sedation (14.6 vs. 13.9%); the three most frequent AEs in the risperidone group (vs. lurasidone) were increased weight (19.8 vs. 9.3%), somnolence (17.8 vs. 13.6%), and headache (14.9 vs. 10.0%). A higher proportion of patients receiving risperidone had at least a 7% endpoint increase in weight (14 vs. 7%). The median endpoint change in prolactin was significantly higher for risperidone (P<0.001). A comparable improvement in efficacy measures was observed with both agents and the rates of relapse were similar. All-cause discontinuation rates were higher for lurasidone versus risperidone. Long-term treatment with lurasidone was generally well tolerated in this study, with minimal effects on weight and metabolic outcomes.