Effect of blonanserin on cognitive function in antipsychotic-naïve first-episode schizophrenia.

The purpose of this study was to evaluate the effects of blonanserin, a novel antipsychotic, on cognitive function in first-episode schizophrenia. Twenty-four antipsychotic-naïve patients with first-episode schizophrenia participated in the study. Blonanserin was given in an open-label design for 8 weeks. The Brief Assessment of Cognition in Schizophrenia-Japanese language version (BACS-J) was administered as the primary outcome measure at baseline and 8 weeks. Clinical evaluation included the Positive and Negative Syndrome Scale (PANSS), the Schizophrenia Quality of Life Scale-Japanese language version (SQLS-J), and the Clinical Global Impression-Severity of Illness Scale (CGI-S). To exclude the possibility of retest effects on the BACS-J, 10 age-matched patients with chronic schizophrenia treated with blonanserin were tested at baseline and after an 8-week interval. Twenty first-episode patients completed the study. Repeated measures analysis of covariance revealed a significant group-by-time interaction effect on the letter fluency task due to better performance in the first-episode group, but not in the control group. Main effect of time or group-by-time interaction effect on the Tower of London task was not significant; however, the first-episode group, but not the control group, showed substantial improvement with a moderate effect size. All items on the PANSS, SQLS-J, and CGI-S significantly improved after 8 weeks of treatment. These results suggest that blonanserin improves some types of cognitive function associated with prefrontal cortical function.