Randomized, controlled, double-blind multicenter comparison of the efficacy and tolerability of ziprasidone and olanzapine in acutely ill inpatients with schizophrenia or schizoaffective disorder

Abstract

Objective: Limited randomized, controlled trial data exist on possible differences between atypical antipsychotics in efficacy, overall tolerability, and important indices of health status. The authors compared the efficacy and tolerability of ziprasidone and olanzapine in the treatment of acutely ill inpatients with schizophrenia or schizoaffective disorder.

Method: In this 6-week, multicenter, double-blind, parallel-design, flexible-dose trial, patients were randomly assigned to receive ziprasidone (N=136) or olanzapine (N=133). Primary efficacy measures were improvement in Brief Psychiatric Rating Scale and Clinical Global Impression (CGI) severity scale scores; secondary measures were scores on the CGI improvement scale, Positive and Negative Syndrome Scale, and Calgary Depression Scale for Schizophrenia. Tolerability assessments included fasting lipid profiles, fasting glucose and insulin measurements, electrocardiography, and monitoring of vital signs and body weight.

Results: The overall mean daily doses were 129.9 mg (SD=27.3) for ziprasidone and 11.3 mg (SD=2.8) for olanzapine. Both antipsychotics were efficacious in improving symptoms and global illness severity. The two treatment groups did not differ significantly in primary or secondary efficacy measures at endpoint or in by-visit analysis. Both agents were well tolerated. Body weight, total cholesterol, triglycerides, and low-density lipoprotein cholesterol significantly increased with olanzapine but not with ziprasidone; all between-group comparisons of these variables were significant and favored ziprasidone. Olanzapine, but not ziprasidone, was associated with significant increases in fasting insulin level. No patient in either group exhibited a corrected QT interval >/=500 msec.

Conclusions: During 6 weeks' treatment, ziprasidone and olanzapine demonstrated comparable antipsychotic efficacy. Differences favoring ziprasidone were observed in metabolic parameters.