Efficacy and tolerability of aripiprazole: a 26-week switching study from oral antipsychotics.

Objective: To determine if the maintenance effectiveness and tolerability of aripiprazole demonstrated in a 12-week study were maintained in an extension phase (up to 26 weeks).

Methods: This study was the extension of our switching study from other antipsychotics to aripiprazole in symptomatically stable patients with schizophrenia or schizoaffective disorder. All the patients were randomly assigned to the aripiprazole group or the non-aripiprazole group. The effectiveness analysis consisted of the comparison of the upper bound of the 95% confidence interval (CI) of the mean Clinical Global Impression-Improvement (CGI-I) score to 4 (no change) at the end of the study.

Results: At the baseline, the aripiprazole group (n=135) and the non-aripiprazole group (n=31) were comparable with respect to their mean ages, gender distribution, baseline Positive and Negative Syndrome Scale scores, and Clinical Global Impression-Severity (CGI-S) scores. The study showed that the mean CGI-I score was 2.92 (95% CI: 2.72-3.12) in the aripiprazole group and 2.81 (95% CI: 2.35-3.26) in the non-aripiprazole group at 26 weeks. In the aripiprazole group, the remission rates at 12 and 26 weeks were 74.8% and 72.6%, respectively, and 80.2% of the patients with remission at 12 weeks maintained their remission state until the end of the study. About one-fourth of the patients in the aripiprazole group reported one or more spontaneous treatment-emergent adverse events, such as insomnia, headache, and nausea.

Conclusion: This study suggested that most clinically stable outpatients with schizophrenia maintain their remission states after being switched to aripiprazole, without serious symptom aggravation and adverse events over a course of 26 weeks.