- Patients have a diagnosis of 1) treatment-resistant schizophrenia or; 2) schizophrenia, chronic (all types) and in a residual phase or in remission, or schizoaffective disorder according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria and are judged to be at chronic risk for reexperiencing suicidal behavior based on history and recent clinical state. In addition, all patients must have a total score on the PANSS of 90 or less.