Cost-effectiveness of tiotropium in elderly patients with severe asthma
Published online: May 1, 2021
An inhaled corticosteroid (ICS) and long-acting beta-agonist (LABA) combination therapy is recommended as the gold standard for asthma. However, it shows a significant therapeutic effect in controlling asthma symptoms in only about 70% of asthma patients. This unmet need in asthma treatments can be addressed by adding long-acting muscarinic antagonists (LAMA) treatment, the traditional gold standard for chronic obstructive pulmonary disease. Adding tiotropium, a kind of LAMA, to ICS/LABA for asthma patients has been shown to lead to significant improvements in pulmonary function and exacerbation rates. Consequently, it is currently considered a preferred add-on controller to ICS/LABA for patients not controlled ICS/LABA. As the mode of action of tiotropium is expected to relieve the symptoms that are attributable to anatomical aging in the elderly’s lungs, several reports have mentioned its potential value in the treatment of elderly patients with severe asthma. However, few studies have focused on specific treatments for elderly asthmatic patients.
In an article recently published in The Journal of Allergy and Immunology: In Practice, Hong and colleagues estimated the cost-effectiveness of adding tiotropium to ICS/LABA in patients with severe asthma using real-world data. They conducted a two-phase study. Phase I was a retrospective cohort study using the National Health Insurance claims data to measure clinical and economic outcomes. In phase II, they constructed a Markov model that included two health states (Asthma controlled and death) and an asthma exacerbation event to evaluate cost-effectiveness from the Korean healthcare system perspective. The results of phase I was used as input variables for the Markov model. The authors estimated cost given in 2018 US dollars, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER). Subgroup analyses for poorly controlled asthma patients (frequent short-acting beta-agonist (SABA) users and frequent exacerbators) were performed.
In elderly patients with severe asthma, the incremental cost and effectiveness in the tiotropium group compared to the ICS/LABA group were $2,281 and 0.038 QALYs, respectively. The ICER was $60,074/QALY, indicating that the addition of tiotropium is not a cost-effective alternative. Meanwhile, two subgroups with poorly controlled asthma showed that adding tiotropium is a cost-effective alternative (frequent SABA users $4,078/QALY, frequent exacerbators $8,332/QALY). Therefore, tiotropium shows a higher cost-effectiveness profile when applied to elderly patients with uncontrolled symptoms. These results using real-world evidence provide information beyond the clinical outcomes reported by randomized clinical trials, providing a complementary basis for establishing the reimbursement criteria of tiotropium for elderly patients with severe asthma.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.