Background: An important proportion of asthma patients remain uncontrolled despite using inhaled corticosteroids and long-acting beta-agonists. Clinical guidelines recommend, in these patients, using add-on long-acting muscarinic antagonists (triple therapy) to treatment with high doses of inhaled corticosteroids-long-acting beta2-agonist (dual therapy). The purpose of this study was to assess the cost-effectiveness of triple therapy versus dual therapy for patients with severe asthma.

Methods: A probabilistic Markov model was created to estimate the cost and quality-adjusted life-years (QALYs) of patients with severe asthma in Colombia. Total costs and QALYS of dual and triple therapy were calculated over a lifetime horizon. Multiple sensitivity analyses were conducted. Cost-effectiveness was evaluated at a willingness-to-pay value of $19,000.

Results: The model suggests a potential gain of 1.55 QALYs per patient per year on triple therapy with respect to dual therapy. We observed a difference of US$304 in discounted cost per person-year on triple therapy with respect to dual therapy. The incremental cost-effectiveness ratio was US$196 in the probabilistic model. In the sensitivity analysis, our base-case results were robust to variations in all assumptions and parameters.

Conclusion: In conclusion, triple therapy in patients with moderate-severe asthma was cost-effective. Using triple therapy emerges with our results as an alternative before using oral corticosteroids or biologics, especially in resource-limited settings.

Keywords: Cost-effectiveness analysis; Decision analysis; Markov model; Tiotropium; Uncontrolled asthma.