Cost-Effectiveness of Mepolizumab Add-On in the Treatment of Severe Eosinophilic Asthma in Chile

Objective: Asthma is one of the 4 leading causes of death worldwide. Severe asthma is associated with poor quality of life, decreased life expectancy, and higher health resources consumption such as the use of oral corticosteroids (OCSs). This study aimed to assess the cost-effectiveness of mepolizumab as an add-on compared with the standard care of the Chilean public health system (combined inhaled corticosteroid therapy and a long-acting beta-agonist, short-acting beta-agonist, and OCS).Materials and Methods: A Markov model was adapted to represent the day-to-day of patients with severe asthma over a lifetime horizon. Deterministic and probabilistic sensitivity analyses were performed to account for the second-order uncertainty of the model. In addition, a risk subgroup analysis was conducted to evaluate the cost-effectiveness of mepolizumab across different risk populations. Results: Mepolizumab produces more benefits than standard of care alone (1 additional quality-adjusted life-year, a decrease of OCS usage, an approximated 11 avoided exacerbations) but it cannot be considered cost-effective in the light of the Chilean threshold (incremental cost-effectiveness ratio: US dollars [USD] 105 967/quality-adjusted life-year vs USD 14896). Despite this, cost-effectiveness increases in specific subgroups, with an incremental cost-effectiveness ratio of USD 44 819 in patients with eosinophil count $ 300 cell/mcL and exacerbation history of at least 4 exacerbations in the past year.Conclusion: Mepolizumab cannot be considered a cost-effective strategy for the Chilean health system. Nevertheless, price discount in specific subgroups improves its cost-effectiveness profile significantly and may offer opportunities for access to specific subgroups.