Introduction: Chronic Obstructive Pulmonary Disease (COPD) is a chronic, progressive disease that is not curable. However, there are effective treatments available. In the UK, long-acting bronchodilators are first-line treatments for COPD patients requiring maintenance therapy, and there are several options available. The aim of this study is to establish, from the UK National Health Service (NHS) perspective, the cost-effectiveness profile of indacaterol, the first once-daily long-acting beta2-agonist (LABA), compared with tiotropium and salmeterol, in patients with moderate to severe COPD. In assessing the cost-effectiveness of COPD therapies, this study has the advantage of using real world evidence on the resource use associated with COPD management across the spectrum of the disease.
Methods: A Markov model was developed with four health states following the GOLD classification for severity of airflow limitation. The model time horizon was 3 years, and the cycle length was 3 months. From each state, patients could experience a severe or non-severe exacerbation, move to a different COPD state, remain in the current state or die. Transition probabilities were based on data from the indacaterol clinical trials. The majority of the resource use data was taken from the Optimum Patient Care Research Database (OPCRD), which contains data from over 20,000 COPD patients in England and Scotland. Cost data were taken from UK-based sources and published literature and presented for the cost year 2011. Health-related quality of life was the main outcome of interest and utility data for the COPD states were based on data from the indacaterol clinical trials and disutility due to exacerbations were taken from the literature. Both one way and probabilistic sensitivity analyses were performed to test the robustness of the results.
Results: Indacaterol dominated in the comparison with salmeterol producing an incremental QALY gain of 0.008 and cost savings of £110 per patient over a 3-year time horizon. In the comparison with tiotropium over the same time horizon, indacaterol remained the dominant strategy, producing an incremental QALY gain of 0.008 and cost savings of £248 per patient. The one-way sensitivity analysis indicates that the proportion of patients in each of the COPD stages and the mortality rate associated with Very Severe COPD are the variables with the largest impact on the results. The probabilistic sensitivity analyses showed that over 72 % and 89 % of the iterations when compared with salmeterol and tiotropium, respectively, produced dominant results for indacaterol.
Conclusion: The analyses demonstrate that indacaterol dominates both tiotropium and salmeterol in the base case and is likely to remain cost-effective under a range of assumptions.