Comparative Cost-Effectiveness of Amisulpride and Olanzapine in the Treatment of Schizophrenia in China.

Background: Both amisulpride and olanzapine are leading treatments for schizophrenia in China. This study aimed to investigate the long-term cost-effectiveness of amisulpride and olanzapine in the treatment of schizophrenia in China.Methods: A decision-analytic Markov model was developed to simulate the lifetime clinical and economic outcomes of schizophrenia treatment from the healthcare payer perspective. The long-term costs and QALYs were estimated. Sensitivity analyses were performed to explore the impact of variance of parameters on the results.Results: Treatment with amisulpride provided an effectiveness gain of 16.59 QALYs at an average cost of USD 25,884 whereas olanzapine resulted in 16.38 QALYs at a cost of USD 34,839 over a lifetime horizon. One-way sensitivity analysis suggested that the most sensitive variable was the unit cost of olanzapine. In a probabilistic sensitivity analysis based on a Monte Carlo simulation with a lifetime horizon, the probability of amisulpride being cost-effective was 99.8% at a willingness-to-pay threshold of USD 9,322, the GDP per capita in China 2018. A scenario analysis with updated olanzapine unit cost suggested an ICER of 7,857 USD/QALY.Conclusions: Amisulpride is likely to be a cost-effective option with increased effectiveness compared with olanzapine in the treatment of schizophrenia patients in China.