Risperidone maintenance treatment in schizophrenia: a randomized, controlled trial

Prevention of relapse is the crucial task in the maintenance treatment of schizophrenia. The investigators in this study sought to determine the duration of maintenance treatment needed with the initial therapeutic dose, in contrast to a reduced dose.

In a multicenter open-label, randomized, controlled study, patients with schizophrenia who were clinically stabilized following an acute episode were randomly assigned to a no-dose-reduction group (initial optimal therapeutic dose continued throughout the study), a 4-week group (initial optimal therapeutic dose continued for 4 weeks, followed by a 50% dose reduction that was maintained until the end of the study), or a 26-week group (initial optimal therapeutic dose continued for 26 weeks, followed by a 50% dose reduction until the end of the study). All patients continued until the last recruited patient completed the 1-year follow-up.

Of the 404 patients who met the entry criteria and were randomly assigned, 374 completed the study. The estimated mean time from entry to relapse was 571 days in the 4-week group, 615 days in the 26-week group, and 683 days in the no-dose-reduction group, with estimated relapse rates of 30.5%, 19.5%, and 9.4%, respectively. Patients in the no-dose-reduction group experienced greater reduction in the severity of psychotic symptoms.

Patients who continued to receive the full risperidone dose used for their acute episode had fewer relapses than those who had dose reductions after 4 weeks or 26 weeks during the maintenance period. There was negligible difference in side effects among the three groups.