A 24-week randomized study of olanzapine versus ziprasidone in the treatment of schizophrenia or schizoaffective disorder in patients with prominent depressive symptoms.

OBJECTIVE: The objective of this study is to compare olanzapine with ziprasidone therapy in patients with schizophrenia or schizoaffective disorder and experiencing depressive symptoms.

METHODS: This randomized, double-blind, 24-week, fixed-dose study compared olanzapine (n = 202) and ziprasidone (n = 192) for patients with schizophrenia or schizoaffective disorder and experiencing prominent depressive symptoms. Outcome measures included change in Calgary Depression Scale for Schizophrenia (CDSS) score from baseline to 8 weeks (primary outcome) and changes in CDSS, Montgomery-Asberg Depression Rating Scales, Positive and Negative Syndrome Scale, and Global Assessment of Functioning (GAF) scores for 24 weeks. Statistical analyses included mixed-effects model repeated measures (primary analysis) and change from baseline to last observation carried forward (LOCF).

RESULTS: At baseline, patients had moderate depressive symptoms (mean Montgomery-Asberg Depression Rating Scales total score, 27.3). For 8 weeks, patients treated with olanzapine or ziprasidone had significant improvements on CDSS. Treatment group differences were not statistically significant (P = 0.493, mixed-effects model repeated measures; P = 0.497, LOCF). For 24 weeks, olanzapine-treated patients showed significantly greater improvements in depressive symptoms (results varied by depression measure and statistical approach) and GAF (P < 0.017, LOCF). A significantly higher proportion of olanzapine-treated patients completed the study (44.6% vs 29.7%; P = 0.003) and remained longer on medication (median, 163 vs 73 days, P < 0.001), compared with ziprasidone-treated patients. Olanzapine-treated patients experienced significantly (P < 0.05) greater increases in triglycerides, HgbA1c, and weight.

CONCLUSIONS: For 24 weeks, olanzapine-treated patients had greater and more sustained participation in treatment, during which time significantly greater improvements were observed in depressive symptoms and GAF scores, along with increases in weight and certain metabolic parameters as compared with ziprasidone-treated patients.