This study modelled the cost-effectiveness of 11 oral antipsychotics for relapse prevention among patients with remitted schizophrenia in Singapore. A network meta-analysis determined the relative efficacy and tolerability of 11 oral antipsychotics (amisulpride, aripiprazole, chlorpromazine, haloperidol, olanzapine, paliperidone, quetiapine, risperidone, sulpiride, trifluoperazine and ziprasidone). The clinical estimates were applied in a Markov model to estimate lifetime costs and quality-adjusted life-years gained. Quality-of-life data were obtained from published literature. Resource utilization and cost data were retrieved from local hospital databases. The annual direct cost of healthcare services for a patient experiencing a relapse episode was three-fold that of a patient not in relapse of schizophrenia. The most favourable pharmacological treatment for relapse prevention was olanzapine with an annual probability of relapse of 0.24 (0.13-0.38) with placebo as a reference of 0.75 (0.73-0.78). Olanzapine emerged as the dominant treatment with the highest quality-adjusted life-years gained and lowest lifetime costs. Ziprasidone, aripiprazole and paliperidone incurred higher lifetime costs compared with no treatment. Probability and cost of relapse were key drivers of cost-effectiveness in sensitivity analyses. The data can help prescribers in choosing appropriate treatment and payers in allocating resources for the clinical management of this serious psychiatric disorder.

Agomelatine, escitalopram and mirtazapine had favourable balance between efficacy and tolerability. In addition, mirtazapine was a cost-effective option in the Singapore healthcare system.

BackgroundFor treatment of patients diagnosed with schizophrenia, comparative long-term effectiveness of antipsychotic drugs to reduce relapses when minimising adverse effects is of clinical interest, hence prompting this review.AimsTo evaluate the comparative long-term effectiveness of antipsychotic drugs.MethodWe systematically searched electronic databases for reports of randomised controlled trials (RCTs) of antipsychotic monotherapy aimed at reducing relapse risks in schizophrenia. We conducted network meta-analysis of 18 antipsychotics and placebo.ResultsStudies of 10 177 patients in 56 reports were included; treatment duration averaged 48 weeks (range 4–156). Olanzapine was significantly more effective than chlorpromazine (odds ratio (OR) 0.35, 95% CI 0.14–0.88) or haloperidol (OR=0.50, 95% CI 0.30–0.82); and fluphenazine decanoate was more effective than chlorpromazine (OR=0.31, 95% CI 0.11–0.88) in relapse reduction. Fluphenazine decanoate, haloperidol, haloperidol decanoate and trifluoperazine produced more extrapyramidal adverse effects than olanzapine or quetiapine; and olanzapine was associated with more weight gain than other agents.ConclusionsExcept for apparent superiority of olanzapine and fluphenazine decanoate over chlorpromazine, most agents showed intermediate efficacy for relapse prevention and differences among them were minor. Typical antipsychotics yielded adverse neurological effects, and olanzapine was associated with weight gain. The findings may contribute to evidence-based treatment selection for patients with chronic psychotic disorders.Declaration of interestR.J.B. received grants from the Bruce J. Anderson Foundation and the McLean Private Donors Psychopharmacology Research Fund.Copyright and usage© The Royal College of Psychiatrists 2016. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) licence.