Six-month, blinded, multicenter continuation study of ziprasidone versus olanzapine in schizophrenia.

Objective: The authors' goal was to compare the efficacy and tolerability of 6 months' treatment with flexible-dose ziprasidone and olanzapine in patients with schizophrenia or schizoaffective disorder.

Method: Brief Psychiatric Rating Scale (BPRS) scores and Clinical Global Impression (CGI) severity scores were obtained for 126 responders to a 6-week acute study of olanzapine and ziprasidone during a blinded 6-month continuation study and optional extension study.

Results: Comparable improvements in BPRS and CGI severity scores were seen with both drugs. Olanzapine produced significant increases from acute-study baseline values in weight and body mass index and within-group increases in total cholesterol, low-density lipoprotein cholesterol, and fasting insulin. Between-group differences were not significant for lipids and insulin. Mean QTc values at endpoint were 407.1 msec (baseline mean=406.0 msec) and 394.4 msec (baseline mean=399.7 msec) for ziprasidone and olanzapine, respectively. No patient had a QTc interval > or =500 msec.

Conclusions: Ziprasidone and olanzapine had comparable long-term efficacy; olanzapine was associated with significant weight gain and metabolic alterations.