Cost‑effectiveness of tiotropium versus omalizumab for uncontrolled allergic asthma
Methods: A probabilistic Markov model was created to estimate the cost and quality-adjusted life years (QALYs) of patients with uncontrolled allergic asthma in Colombia. Total costs and QALYs of three interventions including standard therapy (ICS + LABA), add-on therapy with tiotropium, and add-on therapy with omalizumab, were calculated over a 10-year time horizon. Multiple sensitivity analyses were conducted. Cost-effectiveness was evaluated at a willingness-to-pay value of $19,000.
Results: The model showed that tiotropium was associated with lower cost than standard therapy and omalizumab (US$5590 vs. US$5693 vs. U$18,154 average annual cost per patient), and higher QALYs (11.8 vs. 11.3 vs. 11.9) average per patient), showing dominance respect to standard therapy. The probability that tiotropium provides a more cost-effective use of resources compared with standard therapy exceeds 99% for willingness-to-pay threshold.
Conclusion: Add-on therapy with tiotropium was a cost-effective alternative to omalizumab and standard therapy for uncontrolled allergic asthma. Our study provides evidence that should be used by decision-makers to improve clinical practice guidelines and should be replicated to validate their results in other middle-income countries.
Keywords: Markov model; Omalizumab; cost-effectiveness analysis; decision analysis; uncontrolled asthma.