AN OPEN COMPARISON OF CLOZAPINE AND RISPERIDONE IN TREATMENT-RESISTANT SCHIZOPHRENIA

Background: Clozapine and risperidone are used in treatment-resistant schizophrenia. At present, there are few reported comparisons of these drugs in this population. We report on a consecutive series of treatm ent-resistant schizophrenics given either clozapine or risperidone in open clinical trials. Method: Subjects were treated with clozapine (n= 57) or risperidone (n=29). Pretreatment GAF, CGI, and PANSS scores did not differ between the groups, nor did demographic variables includin g age, age at first hospitalization, years ill, number of previous hos pitalizations, or gender. The mean treatment trial was 12.1 weeks, wit h mean doses of clozapine 420 mg, and risperidone 7.75 mg. The length of the trial did not differ significantly between the groups. Response was taken to be a 20% decrease in the PANSS score. Results: Using rep eated measures ANOVA, PANSS total scores (F=5.3, p=0.02) and positive subscore (F=7.4, p=0.008) showed greater improvement in the clozapine group than the risperidone group, while other PANSS subscores showed a trend toward greater improvement with clozapine. The PANSS-derived fa ctors of excitement (F=6.7, p=0.01), psychosocial withdrawal (F=3.8, p =0.05), and psychomotor retardation (F=3.9, p=0.05) improved more in t he group treated with clozapine. The GAF (F=10.9, p=0.0014), CGI (F=11 .5, p=0.0011), and CGI improvement (p=0.0001) scores also improved mor e in the clozapine group. Of the clozapine group, 25 (44%) responded, while 8 (28%) of the risperidone group responded to treatment. Discuss ion: Clozapine had better efficacy in subjects with treatment-resistan t schizophrenia compared to risperidone, although risperidone appears to yield better response rates than those previously reported for typi cal antipsychotics. Double-blind, controlled trials of risperidone are needed to establish its efficacy in treatment-resistant schizophrenia .