Efficacy and safety of aripiprazole in Chinese Han schizophrenia subjects: a randomized, double-blind, active parallel-controlled, multicenter clinical trial.

OBJECTIVE: Antipsychotics, such as aripiprazole and risperidone, are often used to treat individuals with schizophrenia. The efficacy as well as safety of aripiprazole in Western populations has been described. The objective of this study is to investigate the efficacy, safety, and tolerability of aripiprazole and risperidone in Chinese Han schizophrenia subjects in mainland China.

METHOD: The 6-week, double-blind, randomized, parallel study was conducted in 5 medical centers in mainland China from November 2007 to March 2011. A total of 279 subjects with a primary DSM-IV diagnosis of schizophrenia were randomly assigned (with a randomization ratio of 1:1) to aripiprazole (n=139) or risperidone (n=140). Efficacy measurements included the Positive and Negative Syndrome Scale (PANSS) total, positive, negative and general psychopathology subscale scores, and Clinical Global Impressions-Severity of Illness (CGI-S), and Improvement scale scores. Extrapyramidal symptoms (EPS), weight gain, serum prolactin level, QTc interval, and self-reported adverse events were also assessed as measures of safety and tolerability.

RESULTS: Both the aripiprazole and risperidone groups showed statistically significant improvement of PANSS total, positive, negative, general psychopathology subscale scores, and CGI-S scores from baseline to the endpoint (all p<0.01). Significant improvement was noted in the first week for both treatment groups. There were no significant differences in efficacy measurements between the two treatment groups. Mean change of PANSS total scores from baseline to the endpoint was -26.8±18.1 for aripiprazole and -30.0±17.7 for risperidone, (p=0.1475). The responder rate was 71% (n=99) and 76% (n=107) for aripiprazole and risperidone, respectively, (p=0.323). The incidences of EPS were similar in the aripiprazole (25%, n=35) and risperidone groups (24%, n=34), respectively (p=0.757). No clinically meaningful effects on QTc interval, QRS duration, or PR interval were observed in either treatment groups. However, the incidence of clinically significant weight gain (p=0.0118) and hyperprolactinemia (p<0.001) in the aripiprazole group was significantly lower than in the risperidone group.

CONCLUSION: The study demonstrated that aripiprazole, as well as risperidone, had rapid and persistent efficacy for psychotic symptoms from the first week of therapy. There may be poor efficacy for aripiprazole compared with risperidone for overall improvement, but there were no significant differences in this study. Aripiprazole showed good tolerability with less weight gain and hyperprolactinemia compared with risperidone. The overall efficacy and safety of aripiprazole in Chinese Han schizophrenia subjects were similar to that reported in Western populations.