Efficacy and safety of olanzapine, an atypical antipsychotic, in patients with schizophrenia: Results of an open‐label multicenter study in Japan

Abstract

This first clinical study of olanzapine in Japanese patients with schizophrenia was conducted to investigate the efficacy and safety of olanzapine. Eighty-one patients were included in the analysis set. Mean modal dose for those patients were 9.4 +/- 3.6 mg/day. For the primary efficacy measure (Final Global Improvement Rating score), 14.8% of patients had remarkable improvement, 59.3% of patients had moderate improvement or better, and 86.4% of patients had slight improvement or better. Results from the Brief Psychiatric Rating Scale showed improvement from baseline in all clusters including positive psychotic symptoms (thought disturbance) but also against negative symptoms (anergia). The most commonly reported treatment-emergent signs and symptoms with > or =10% incidence, were insomnia, weight increase, excitement, sleepiness, and anxiety. There was a low incidence of extrapyramidal treatment-emergent signs and symptoms, and events reported were tremor (6.2%), muscle rigidity (3.7%), and akathisia (2.5%). The most commonly reported treatment-emergent laboratory changes, with > or = 20% of incidence, were prolactin elevations (24.3%) followed by increases in triglycerides (20.4%). However, mean prolactin values tended to be normalized during the study. This study result suggests that olanzapine is an "atypical" antipsychotic.