Background: Little is known about the combination of different medications in chronic obstructive pulmonary disease (COPD). This study determined the cost effectiveness of adding salmeterol (S) or fluticasone/salmeterol (FS) to tiotropium (T) for COPD.
Methods: This concurrent, prospective economic analysis was based on costs and health outcomes from a 52 week randomized study comparing: 1: T 18 μg once daily + placebo twice daily (TP group), 2: T 18 μg once daily + S 25 μg/puff, 2 puffs twice daily (TS group), and 3: T 18 μg once daily + FS 250/25 μg/puff, 2 puffs twice daily (TFS group). The incremental cost effectiveness ratios (ICERs) were defined as incremental cost per exacerbation avoided, and per additional quality adjusted life year (QALY) between treatments. A combination of imputation and bootstrapping was used to quantify uncertainty and extensive sensitivity analyses were performed.
Results: The average patient in the TP group generated $2,678 in direct medical costs, compared to $2,801 (TS) and $4,042 (TFS). The TS strategy was dominated by TP and TFS. Compared with TP, the TFS strategy resulted in ICERs of $6,510 per exacerbation avoided, and $243,180 per QALY gained. In those with severe COPD, TS resulted in equal exacerbation rates and slightly lower costs when compared to TP.
Conclusions: TFS had significantly better quality of life and fewer hospitalizations than patients treated with TP, however, these improvements in health outcomes were associated with increased costs. Neither TFS nor TS are economically attractive alternatives compared with monotherapy with T.