Subjects were patients with schizophrenia or schizoaffective disorder enrolled in extension studies (Study A and Study B) after participating in 12-week studies of long-acting injectable risperidone [Kane, J.M., Eerdekens, M., Lindenmayer, J.-P., Keith, S.J., Lesem, M., Karcher, K., 2003. Long-acting injectable risperidone: efficacy and safety of the first long-acting atypical antipsychotic. Am. J. Psychiatry 160, 1125-1132; Lindenmayer, J.-P., Eerdekens, L., Berry, S., Eerdekens, M., 2004. Safety and efficacy of long-acting risperidone in schizophrenia: a 12-week, multicenter, open-label study in stable patients switched from typical and atypical oral antipsychotics. J. Clin. Psychiatry 65, 1084-1089]. Twelve months of treatment were completed by 55% of Study A patients and 52% of Study B patients. The median modal dose of long-acting injectable risperidone was 50 mg/14 days in both studies. Most frequent adverse events were psychosis, headache, insomnia, agitation, and rhinitis. EPS-related adverse events were reported in 33% of patients in Study A and 22% in Study B. Patients with Clinical Global Impressions ratings of "not ill" and "mild" increased from 14% at baseline to 54% at endpoint in Study A and from 42% to 65% in Study B. It is concluded that treatment with long-acting injectable risperidone for 1 year or longer appeared to be safe and well tolerated in patients with schizophrenia or schizoaffective disorder.