A 28-Week Comparison of Ziprasidone and Haloperidol in Outpatients With Stable Schizophrenia

Background: Ziprasidone is a novel antipsychotic with a unique pharmacologic profile. This study compared ziprasidone with the conventional antipsychotic haloperidol in outpatients with stable schizophrenia.

Method: Three hundred one outpatients with stable chronic or subchronic schizophrenia (DSM-III-R) were randomized and participated in this double-blind, multicenter, parallel-group clinical study comparing flexible-dose oral ziprasidone, 80-160 mg/day (N=148), with haloperidol, 5-15 mg/day (N=153), over 28 weeks. Patients were assessed using the Positive and Negative Syndrome Scale (PANSS), the Clinical Global Impressions-Severity of Illness scale, the Montgomery-Asberg Depression Rating Scale, the Simpson-Angus Scale, the Barnes Akathisia Scale, and the Abnormal Involuntary Movement Scale.

Results: Modal doses at endpoint were 80 mg/day for ziprasidone and 5 mg/day for haloperidol. Improvements in all mean efficacy variables with both ziprasidone and haloperidol were observed. Significantly more patients were categorized as negative symptom responders (20% reduction in PANSS negative subscale score) in the ziprasidone group (48%) compared with the haloperidol group (33%) (p<.05). Ziprasidone had clear advantages over haloperidol in all evaluations of movement disorders. Changes in body weight were negligible with both treatments. No pattern of laboratory or cardiovascular changes was observed.

Conclusion: Ziprasidone and haloperidol were both effective in reducing overall psychopathology; ziprasidone demonstrated effective treatment of negative symptoms and was better tolerated than haloperidol. Ziprasidone appears to offer an effective alternative to haloperidol in the long-term treatment of stable outpatients with schizophrenia.