OBJECTIVES: This study aims to assess the cost-effectiveness of reslizumab for patients with severe eosinophilic asthma uncontrolled with high-dose inhaled corticosteroids and long-acting β-agonists (ICS/LABA) in Korea.

METHODS: A Markov model with a limited societal perspective was used to compare the costs and quality-adjusted life years (QALYs) of add-on therapy of reslizumab with usual care (i.e., high-dose ICS/LABA) versus usual care alone. The model adopted a cycle length of four weeks with six health states over a lifetime horizon (60 years): controlled asthma, uncontrolled asthma, moderate exacerbation, severe exacerbation, all-cause death, and asthma-related death. The population was adult patients (≥18 years) with severe eosinophilic asthma (eosinophils ≥400 cells/μL) at Global Initiative for Asthma (GINA) steps 4/5 who had experienced at least three exacerbations in the preceding year. Model inputs were largely sourced from individual patient-level data from two 52-week randomized controlled trials of reslizumab (NCT01287039/NCT01285323). Cost data was mainly from National insurance statistical data and survey from asthma specialists in Korea. Utility values were derived from survey results from general population to capture the Korean-specific values. The model included discontinuation rules where patients uncontrolled with reslizumab add-on therapy were transitioned to the usual care arm. The outcome of interest was incremental cost-effectiveness ratio (ICER), expressed as cost per QALYs gained using 5% discount rate and 2018 currency value. Both deterministic and probabilistic sensitivity analyses were performed.

RESULTS: Add-on therapy of reslizumab with usual care was associated with both increased cost (US$114,110) and improved QALYs (5.17) compared with usual care alone, resulting in an ICER of US$22,060 per QALY gained. Body weight, time horizon, and discount rate were influential factors in the model.

CONCLUSIONS: The addition of reslizumab to high-dose ICS/LABA was found to be cost-effective in Korean with severe eosinophilic asthma uncontrolled with high-dose ICS/LABA, based on the threshold of 1 GDP in Korea.