OLANZAPINE IN TREATMENT-REFRACTORY SCHIZOPHRENIA - RESULTS OF AN OPEN-LABEL STUDY

Background: Clozapine is currently the treatment of choice for neurole ptic-resistant schizophrenia. Olanzapine is a new antipsychotic drug t hat has shown efficacy against positive and negative symptoms of schiz ophrenia, with minimal extrapyramidal side effects. However, the effec tiveness of olanzapine has not yet been reported among treatment-refra ctory schizophrenic patients, Method: A total of 25 schizophrenic pati ents (DSM-IV criteria) with documented lack of response to two convent ional antipsychotic drugs entered this 6-week prospective, open-label treatment trial with olanzapine 15 to 25 mg/day. An optional extension up to 6 months was provided, Results: As a group, the olanzapine-trea ted patients showed statistically significant improvement (p < .05) in both positive and negative symptoms by the end of 6 weeks of therapy. Overall, 9 of the patients (36%) met the a priori criteria for treatm ent-response (greater than or equal to 35% decrease in Brief Psychiatr ic Rating Scale [BPRS] total score, plus posttreatment Clinical Global Impression-Severity less than or equal to 3 or BPRS total < 18), Only one patient discontinued treatment because of an adverse event during the study, Despite the relatively high dosages of olanzapine used, me re were no reports of parkinsonism, akathisia, or dystonia, and no pat ients required anticholinergic medication. Conclusion: This open study suggests that olanzapine may be effective and well tolerated fur a su bstantial number of neuroleptic-resistant schizophrenic patients, Furt her blinded, controlled trials are needed to confirm our results.