This is an open-label, long-term study of a flexible dose of a long-acting injectable formulation of risperidone (risperidone LAI) injected into the muscle at 2 week intervals for at least 12 months in patients diagnosed with schizophrenia. It is an extension of an open label study of patients with schizophrenia (RIS-USA-259) switching from treatment with an oral antipsychotic medication to long-acting injectable risperidone. Safety evaluations include incidence of adverse events, physical examinations, clinical laboratory tests (biochemistry, hematology, and urinalysis), electrocardiograms (ECGs), and Extrapyramidal Symptom Rating Scale (ESRS), a scale for assessing muscle tone, gait, and abnormal movements. Efficacy assessments include measurements using the Positive and Negative Syndrome Scale for Schizophrenia (PANSS) and the Clinical Global Impression-Severity of Illness scale (CGI-S). Risperidone (25-50milligrams [mg]) injections, long-acting formulation, every 2 weeks for at least 1 year. Dosages may be increased (50 mgs maximum) or decreased at discretion of the investigator. Supplementary risperidone tablets (1mg) may be administered.
The purpose of this study is to document the long term safety of a long-acting injectable formulation of risperidone in the treatment of patients with schizophrenia who have previously been treated with long-acting risperidone. Efficacy will also be evaluated.