Clinical and economic outcomes of olanzapine compared with haloperidol forschizophrenia - Results from a randomised clinical trial

Objective: The purpose of this study was to compare, from the payor perspec tive, the clinical and economic outcomes of olanzapine to those of haloperi dol for the treatment of schizophrenia. Design and setting: Clinical, quality-of-life and resource utilisation data were prospectively collected for US-residing patients with schizophrenia w ho were participating in a multicentre, randomised, double-blind clinical t rial comparing olanzapine and haloperidol. Direct medical costs were estima ted by assigning standardised prices (1995 values) to the resource utilisat ion data. Patients and participants: X17 patients with schizophrenia who had a baseli ne Brief Psychiatric Rating Scale score (BPRS) greater than or equal to 18 (items scored 0 to 6) and/or were no longer tolerating current antipsychoti c therapy. Interventions: Olanzapine 5 to 20 mg/day (n = 551) or haloperidol 5 to 20 m g/day (n = 266) for 6 weeks. Patients showing a predefined level of clinica l response entered a 46-week maintenance phase. Main outcome measures and results: After acute treatment, BPRS-based clinic al improvements were seen in 38 and 27% of olanzapine and haloperidol patie nts, respectively (p = 0.002). Clinically important improvements on the Qua lity of Life Scale were achieved during acute treatment in 33% of olanzapin e recipients and 25% of haloperidol recipients (p = 0.094). Olanzapine trea tment in the acute phase led to significantly lower inpatient ($US5125 vs $ US5795, p = 0.038) and outpatient ($US663 vs $US692, p = 0.001) costs, resu lting in a significant overall reduction in mean total medical costs of $US 388 (p = 0.033). This significant reduction in total costs was found despit e olanzapine mean medication costs being significantly greater than haloper idol medication costs ($US326 vs $US15, p < 0.001). No significant differen ces in clinical improvement were observed in the maintenance phase. Mainten ance phase olanzapine mean total medical costs were $US636 lower than halop eridol total costs (p = 0.128). Although olanzapine medication costs were s ignificantly higher than haloperidol medication costs ($US3461 vs $US95, p < 0.001), this difference was offset by significantly lower inpatient ($US8 322 vs $US10662, p = 0.014) and outpatient ($US3810 vs $US5473, p = 0.038) costs. Conclusions: In this study, olanzapine treatment was more effective than ha loperidol in producing clinical response in the acute phase. In addition, o lanzapine treatment led to reductions in inpatient and outpatient costs tha t more than offset olanzapine's higher medication costs relative to haloper idol.