Cost-Effectiveness Analysis of Omalizumab Combined With Standard of Care in Treating Moderate to Severe Asthma Children in China

Abstract

Objectives: It has been recognized that adding omalizumab to standard of care (SOC) is a promising treatment for pediatric moderate to severe asthma patients in the Chinese setting, as shown by a previous multicenter retrospective study. Nevertheless, there is as yet no concrete evidence of its economic advantages. Several international studies conducted in different countries have shown varying results. The study is designed to better demonstrate the economic impact of omalizumab for Chinese children with asthma. Methods: Based on consultation with physicians, a three-state Markov model was developed. The progress of asthma is modeling using the states “no symptoms,” “secondary control, no asthmatic attack” and “asthmatic attack.” To better reflect clinical treatment, exacerbation state was further divided into “exacerbation with outpatient service” and “exacerbation with hospitalization.” To understand the effects of treatment, the response rate of omalizumab was also modeled. The modeling cycle length was set at 1 week over a 5-year time horizon. Clinical effect and transition probabilities were sourced from published literature, while cost data were primarily obtained from local databases. Cost-effectiveness analysis was assessed from the health system perspective. One-way sensitivity analyses and scenario analysis were performed to ensure the robustness of the results. The willingness-to-pay (WTP) threshold was set at 1 GDP/capital, as recommended by the national guidelines. Results: It was shown that adding omalizumab to SOC treatment would increase both the total cost and quality-adjusted life years (QALYs) over 5 years, with an incremental cost-effectiveness ratio (ICER) of CNY 111,644.77/QALY, which is higher than the WTP threshold. Among the parameter variations, the two factors that altered the results were the proportion of hospitalizations in SOC therapy during asthma exacerbation and the weekly cost of omalizumab with full dose, which were both negatively correlated with the ICER. Scenario analysis, simulating the Medicare reimbursement conditions, reduced the ICER to an acceptable level. Conclusions: Adding omalizumab to SOC treatment in pediatric moderate to severe asthma patients would be a cost-effective choice under the current medical insurance reimbursement policy in China.