Switching Antipsychotics to Blonanserin in Patients with Schizophrenia: An Open-label, Prospective, Multicenter Study

Objective: This study was performed to investigate the efficacy and tolerability of blonanserin in schizophrenic patients who were previously treated with other antipsychotics but, due to insufficient response, were switched to blonanserin. Methods: A total of 52 patients with schizophrenia who were unresponsive to treatment with antipsychotic monotherapy or combination therapy were recruited into this 12-week, open-label, prospective, multicenter study. Patients were switched to blonanserin from their existing antipsychotics over a maximum 2-week tapering-off period. Efficacy was primarily evaluated using the 18-item Brief Psychiatric Rating Scale (BPRS). Assessments were performed at baseline, and at weeks 1, 2, 4, 8, and 12. Results: Switching to blonanserin resulted in a significant decrease in the mean total score on the BPRS from baseline (56.8 ± 9.4) to week 12 (42.1 ± 13.8, p ＜ 0.001). The most common adverse events were extrapyramidal symptoms (n = 12, 23.1%), insomnia (n = 10, 19.2%), and emotional arousal (n = 6, 11.5%). Overweight or obese patients (body mass index ≥ 23 kg/m², n = 33) who switched to blonanserin exhibited significant weight loss from 75.2 ± 9.3 kg at baseline to 73.5 ± 9.2 kg at week 12 ( p = 0.006). The total cholesterol (baseline, 236.1 ± 47.6 mg/dl; endpoint [week 12], 209.9 ± 28.0 mg/dl; p = 0.005) and prolactin levels (baseline, 80.0 ± 85.2 ng/ml; endpoint [week 12], 63.2 ± 88.9 ng/ml; p = 0.003) were also significantly improved in patients with hypercholesterolemia or hyperprolactinemia. Conclusion: The results of the present study suggest that switching to blonanserin may be an effective strategy for schizo-phrenic patients unresponsive to other antipsychotic treatments.