Cost effectiveness of tiotropium in patients with asthma poorly controlled on inhaled glucocorticosteroids and long-acting β-agonists.

BACKGROUND: A considerable proportion of patients with asthma remain uncontrolled or symptomatic despite treatment with a high dose of inhaled glucocorticosteroids (ICSs) and long-acting β2-agonists (LABAs). Tiotropium Respimat(®) added to usual care improves lung function, asthma control, and the frequency of non-severe and severe exacerbations, in a population of adult asthma patients who are uncontrolled despite treatment with ICS/LABA. OBJECTIVE: This study estimated the cost effectiveness of tiotropium therapy as add-on to usual care in asthma patients that are uncontrolled despite treatment with ICS/LABA combination from the perspective of the UK National Health Service (NHS). METHODS: A Markov model was developed which considers levels of asthma control and exacerbations. The model analysed cost and quality-adjusted life-years (QALYs); sensitivity and scenario analyses were also conducted to test the robustness of the base case outcomes. All costs are given at 2012 prices. RESULTS: The model found that in this category of asthma with unmet need, add-on tiotropium therapy generated an incremental 0.24 QALYs and £5,238 costs over a lifetime horizon, resulting in an incremental cost-effectiveness ratio of £21,906 per QALY gained. Sensitivity analysis suggested that findings were most dependent on the costs of managing uncontrolled asthma and the cost of treatment with tiotropium. CONCLUSION: In this modelled analysis of two clinical trials, tiotropium was found to be cost effective when added to usual care in patients who remain uncontrolled despite treatment with high-dose ICS/LABA. Further research should investigate the long-term treatment effectiveness of tiotropium.