Although currently marketed antipsychotic drugs are useful in the treatment of schizophrenia, efficacy and safety profiles need to be improved. Forty to eighty percent of patients either fail to respond or only partially respond to conventional antipsychotic agents. Secondary symptoms may be unimproved even in patients who respond to treatment. A variety of adverse events occur in patients receiving currently available agents. The severity of these events contributes to the poor compliance that is observed in this patient population. Olanzapine is a novel antipsychotic agent with a reduced incidence of extrapyramidal symptoms. Other side effects are minimal.

Primary Hypothesis: To determine if olanzapine is more cost effective than haloperidol for the treatment of schizophrenia.

Secondary Hypothesis: Secondary objectives include evaluation of clinical efficacy, safety, social and vocational functioning, family burden, compliance and satisfaction for olanzapine relative to haloperidol.

Intervention: Olanzapine (5 mg to 20 mg/day), haloperidol (5 mg to 20 mg/day).

Primary Outcomes: Total inpatient hospital care costs are the primary outcome. Other major outcomes are total social costs (cost of VA health care, non-VA services and other specified social costs), efficacy measures (PANNS, BPRS, CGI Severity, and neurocognitive battery scores) and safety measures (adverse events, ECG?s).

Study Abstract: Although currently marketed antipsychotic drugs are useful in the treatment of schizophrenia, efficacy and safety profiles need to be improved. Forty to eighty percent of patients either fail to respond or only partially respond to conventional antipsychotic agents. Secondary symptoms may be unimproved even in patients who respond to treatment. A variety of adverse events occur in patients receiving currently available agents. The severity of these events contributes to the poor compliance that is observed in this patient population. Olanzapine is a novel antipsychotic agent with a reduced incidence of extrapyramidal symptoms. Other side effects are minimal.

Approximately 327 patients with schizophrenia or schizoaffective disorder were randomly assigned to one of two treatment groups. One treatment group was prescribed olanzapine with daily dosage ranging from 5 mg/day to 20 mg/day. The other treatment group was prescribed haloperidol with daily dosage also ranging from 5 mg/day to 20 mg/day. A semi-structured psychosocial case management treatment program is provided for all study patients. Patients were recruited from 18 VA medical centers over a 24-month period and were followed for one year. 18 patients were enrolled at one site that had its research program terminated during the study. Because of questions regarding the circumstances that led to the termination, these 18 patients will not be included in study analyses. The major objective of the study is to determine if olanzapine is more cost effective than haloperidol. Secondary objectives include evaluation of clinical efficacy, safety, social and vocational functioning, family burden, compliance and satisfaction for olanzapine relative to haloperidol.

MANUSCRIPT: Primary manuscript published in JAMA, November 2003.

Patients with schizophrenia or schizoaffective disorder.