Results
Of 1497 included patients who transitioned from budesonide/formoterol to fluticasone/salmeterol inhalers, 165 were randomly selected and 100 patients were included in this analysis. Of the 100 patients, 99 were male with a mean (SEM) age of 71 (0.69) years (range, 54-87) (Table).
The transition from budesonide/formoterol to fluticasone/salmeterol inhalers did not have a statistically significant impact on exacerbations (P = .56). Thirty patients had ≥ 1 exacerbation: 12 had an exacerbation before the transition, 10 had an exacerbation after the transition, and 8 had exacerbations before and after the transition. In the 6 months prior to the transition while on a budesonide/formoterol inhaler, there were 24 exacerbations among 20 patients. Five patients had > 1 exacerbation, accounting for 11 of the 24 exacerbations. There were 29 exacerbations among 19 patients while on a fluticasone/salmeterol inhaler in the 6 months after the transition. Four of these patients had > 1 exacerbation, accounting for 14 of 29 exacerbations (Figure).
Secondary endpoints showed 3 patients experienced an AE related to fluticasone/salmeterol, including thrush, coughing and throat irritation, and dyspnea. Eighteen fluticasone/salmeterol therapeutic failures were indicated by related prior authorization medication requests in the electronic health record. Twelve of 18 patients experienced no difference in exacerbations before vs after the transition to budesonide/formoterol. Twenty-three patients transitioned from fluticasone/salmeterol to a different ICS-LABA therapy; 20 of those 23 patients transitioned back to a budesonide/formoterol inhaler.
There were 48 documented active tobacco users in the study. There was no statistically significant correlation (P = .52) when comparing tobacco use at time of conversion and exacerbation frequency, although the coefficient showed a negative correlation of -0.387. In the 6 months prior to the transition, there were 17 prescriptions for systemic corticosteroids and 24 for antibiotics to treat COPD exacerbations. Following the transition, there were only 12 prescriptions for systemic corticosteroids and 23 for antibiotics. Fifty-two patients had an active prescription for a fluticasone/salmeterol inhaler at the time of the data review (November to December 2022); of the 48 patients who did not, 10 were no longer active due to patient death between the study period and data retrieval.
Discussion
Patients who transitioned from budesonide/formoterol to fluticasone/salmeterol inhalers did not show a significant difference in clinical COPD outcomes. While the total number of exacerbations increased after switching to the fluticasone/salmeterol inhaler, fewer patients had exacerbations during fluticasone/salmeterol therapy when compared with budesonide/fluticasone therapy. The number of patients receiving systemic corticosteroids and antibiotics to treat exacerbations before and after the transition were similar.
The frequency of treatment failures and AEs to the fluticasone/salmeterol inhaler could be due to the change of the inhaler delivery systems. Budesonide/formoterol is a metered dose inhaler (MDI). It is equipped with a pressurized canister that allows a spacer to be used to maximize benefit. Spacers can assist in preventing oral candidiasis by reducing the amount of medication that touches the back of the throat. Spacers are an option for patients, but not all use them for their MDIs, which can result in a less effective administered dose. Fluticasone/salmeterol is a dry powder inhaler, which requires a deep, fast breath to maximize the benefit, and spacers cannot be used with them. MDIs have been shown to be responsible for a negative impact on climate change, which can be reduced by switching to a dry powder inhaler.7
Tobacco cessation is very important in limiting the progression of COPD. As shown with the negative coefficient correlation, not being an active tobacco user at the time of transition correlated (although not significantly) with less frequent exacerbations. When comparing this study to similar research, such as the PATHOS study, several differences are observed.5 The PATHOS study compared long term treatment (> 1 year) of budesonide/formoterol or fluticasone/salmeterol, a longer period than this study. It regarded similar outcomes for the definition of an exacerbation, such as antibiotic/steroid use or hospital admission. While the current study showed no significant difference between the 2 inhalers and their effect on exacerbations, the PATHOS study found that those treated with a budesonide/formoterol inhaler were less likely to experience COPD-related exacerbations than those treated with the fluticasone/salmeterol inhaler. The PATHOS study had a larger mainly Scandinavian sample (N = 5500). This population could exhibit baseline differences from a study of US veterans.5 A similar Canadian matched cohort study of 2262 patients compared the 2 inhalers to assess their relative effectiveness. It found that COPD exacerbations did not differ between the 2 groups, but the budesonide/formoterol group was significantly less likely to have an emergency department visit compared to the fluticasone salmeterol group.8 Like the PATHOS study, the Canadian study had a larger sample size and longer timeframe than did our study.