The efficacy of zotepine in schizophrenia: A meta-analysis of BPRS and improvement scale scores

Abstract

OBJECT: To assess the efficacy of the antipsychotic drug zotepine in the treatment of the global psychopathology of schizophrenia. METHOD: Fifteen randomized placebo- or antipsychotic comparator- controlled trials were analysed, using the Brief Psychiatric Rating Scale (BPRS) or other improvement scales. A meta-analysis of standardized treatment differences and a test for homogeneity were performed on four comparator groups: all placebo-controlled trials, all antipsychotic comparator-controlled trials, conventional antipsychotic comparator-controlled trials, and antipsychotic comparator-controlled trials excluding those in which the dosage for zotepine exceeded 75-300 mg/day (the recommended dose in the UK). The outcome measure used in the meta-analysis was the change in rating score. RESULTS: Meta-analysis of the placebo-controlled trials showed that a significantly greater reduction in BPRS occurred with zotepine therapy than with placebo therapy. The reduction in rating score was also greater with zotepine therapy than with antipsychotic comparators. Exclusion of the high-dose zotepine studies did not alter these conclusions. Only in one trial, in which zotepine was compared with the atypical antipsychotic clozapine, was there a greater reduction in rating score with the comparator than with zotepine (not statistically significant). All tests of homogeneity failed to reach significance, demonstrating that the data were not influenced by inter-study heterogeneity. CONCLUSION: Zotepine is at least as effective against all psychopathological symptoms of schizophrenia as conventional antipsychotics. (Int J Psych Clin Pract 2000; 4:19-27)