Effectiveness of blonanserin for patients with drug treatment-resistant schizophrenia and dopamine supersensitivity: A retrospective analysis.

OBJECTIVE: Dopamine supersensitivity psychosis (DSP) is one of the key factors contributing to the development of antipsychotic treatment-resistant schizophrenia (TRS). We investigated the efficacy of blonanserin, an atypical antipsychotic, for patients with TRS and DSP.

METHODS: In this 12-month retrospective follow-up study, we investigated the cases of eight consecutive patients with unstable TRS and DSP treated with blonanserin as an add-on therapy. We examined changes in scores for the Brief Psychiatric Rating Scale (BPRS), Clinical Global Impression-Severity of Illness (CGI-S) scale and the Global Assessment of Functioning scale (GAF) during the 12 months after the administration of blonanserin.

RESULTS: The patients' total scores on the BPRS and GAF scores were significantly improved by 3 months at the latest. Positive BPRS and CGI-S scores were also improved by 6 months at the latest. The total chlorpromazine-equivalent doses of antipsychotics were significantly reduced from 1462.3±499.6mg to 794.1±642.8mg (p=0.001) after 12 months of blonanserin treatment, with a favorable safety and tolerability profile.

CONCLUSIONS: Blonanserin may be a promising antipsychotic for the treatment of TRS and DSP.