Oral olanzapine versus oral haloperidol in the maintenance treatment of schizophrenia and related psychoses.

BACKGROUND: Three studies compared olanzapine and haloperidol given orally in maintenance therapy for schizophrenia and related psychoses. METHOD: Data were from double-blind extensions of acute studies. The subjects met criteria for schizophrenia, schizophreniform disorder or schizoaffective disorder. Subjects had responded to acute therapy (Brief Psychiatric Rating Scale total score decreased > or = 40% from baseline (Studies 1, 2, and 3) or was < or = 18 (Studies 1 and 2)) and were out-patients at their last acute phase visit. Relapse was defined as hospitalisation for psychopathology. Subjects treated with olanzapine in the three studies were pooled to form the olanzapine group and subjects treated with haloperidol were pooled to form the haloperidol group. RESULTS: Olanzapine-treated subjects experienced less relapse (P = 0.034). The Kaplan-Meier estimated one-year risk of relapse was 19.7% with olanzapine and 28% with haloperidol. CONCLUSION: Olanzapine was superior to haloperidol in the maintenance therapy of schizophrenia and related psychoses. DECLARATION OF INTEREST: This work was sponsored by Eli Lilly and Company.

Standard olanzapine versus placebo and ineffective-dose olanzapine in the maintenance treatment of schizophrenia.

OBJECTIVE: Two studies compared the efficacy of standard-dose oral olanzapine (5 to 15 mg a day) with placebo and with ineffective-dose olanzapine (1 mg a day) in maintenance therapy of schizophrenia. METHODS: The studies were 46-week double-blind extensions of multicenter studies that assessed the efficacy of olanzapine in the acute treatment of schizophrenia. Subjects were 120 adults who met DSM-III-R criteria for schizophrenia with an acute exacerbation and who had a minimum score of 24 on the Brief Psychiatric Rating Scale, who had responded to acute therapy (defined as at least a 40 percent reduction in the BPRS score from baseline or a score of 18 or less during up to six weeks of treatment), and who were outpatients at their last acute-phase visit. Relapse was defined as hospitalization for psychopathology. Relapse risk was analyzed using Kaplan-Meier survival analysis and life table analysis. Patients who relapsed were discontinued from the studies. RESULTS: In the first study (N = 58), patients in the standard-dose olanzapine group experienced a significantly lower relapse risk (p = .002) over one year than patients treated with placebo. The estimated one-year risk of relapse with olanzapine was 28.6 percent, compared with 69.9 percent with placebo. Results were similar in the second study (N = 62); patients treated with standard-dose olanzapine had a significantly reduced risk of relapse (p = .018) over one year compared with patients treated with ineffective-dose olanzapine. The estimated one-year risks of relapse were 19.6 percent for standard-dose olanzapine and 45.5 percent for ineffective-dose olanzapine. CONCLUSIONS: Olanzapine is superior to placebo and ineffective-dose olanzapine in the maintenance therapy of schizophrenia.