LONDON – In chronic obstructive pulmonary disease (COPD), the advantage of a long-acting beta agonist (LABA) plus a long-acting muscarinic antagonist (LAMA) over a LABA plus an inhaled corticosteroid (ICS) was observed in every subgroup in the FLAME trial evaluated, according to post hoc analyses presented at the annual congress of the European Respiratory Society.
“We thought that we might not see the difference in the COPD patients with more severe disease, but the advantage was consistent even among those who entered the trial on triple therapy,” reported Jadwiga A. Wedzicha, MD, professor of respiratory medicine at the National Heart and Lung Institute, Imperial College, London.
FLAME, the recently published study that compared LABA/LAMA to LABA/ICS, was planned as a noninferiority study with the underlying hypothesis that LABA/LAMA would perform as well as LABA/ICS for the primary outcome of annual rate of COPD exacerbations (N Engl J Med. 2016;374:2222-34). Instead, the 11% lower rate of exacerbations for LABA/LAMA proved statistically significant (P = .003).
Six post hoc FLAME analyses were presented at the 2016 ERS Congress to further explore this result. All supported the main result. In addition to evaluating those who entered the trial on a LABA/LAMA/ICS triple-therapy combination, the analyses covered a broad array of subgroups defined by age, smoking history, and COPD severity as defined by Global Initiative for Chronic Obstructive Lung Disease (GOLD) classifications.
In FLAME, 3,362 COPD patients who had at least one exacerbation in the preceding year were randomized to the LABA indacaterol (110 mcg) plus the LAMA glycopyrronium (50 mcg) once daily or the combination of the LABA salmeterol (50 mcg) and the ICS fluticasone (500 mcg) twice daily. In addition to the relative advantage on the primary outcome of any exacerbation, the LABA/LAMA combination also significantly reduced the rate of moderate to severe exacerbations (P less than .001), and it extended the times to the first moderate to severe exacerbation (P less than .001) and the first severe exacerbation (P = .046), according to the published data.
In the post hoc analyses, the advantage of LABA/LAMA relative to LAMA/ICS was remarkably consistent. For example, in stratifications made for age (less than 55 years, 55 to less than 65 years, 65-75 years, and greater than or equal to 75 years) at least a numerical advantage of LABA/LAMA was seen in all age groups for prevention of any exacerbation, and the difference reached statistical significance for those in the age group 55 to greater than 65 years. For prevention of moderate to severe exacerbations, the treatments were found to be equivalent for individuals younger than 55 years, but LABA/LAMA was statistically superior for the other three age categories.
For ex-smokers, unlike current smokers, the numerical advantage of LABA/LAMA over LABA/ICS for reduction in the rate ratio of all exacerbations did not reach statistical significance, but the LABA/LAMA combination did provide a statistically significant advantage for both ex-smokers and current smokers for moderate to severe exacerbations.
For patients with two or more exacerbations in the year prior to enrollment in FLAME, the relative degree of protection was of magnitude similar to that of patients with only one exacerbation even though the relative advantage in those with multiple prior exacerbations did not reach statistical significance. However, the lack of significance was likely due to the relatively small number of patients in this subpopulation, according to Dr. Wedzicha.
Similarly, the LABA/LAMA combination was at least numerically superior to LABA/ICS for all exacerbations and for moderate to severe exacerbations across GOLD classifications with one exception. When compared for relative protection against moderate to severe exacerbations, there was a slight and nonsignificant disadvantage for LABA/LAMA, but, again, Dr. Wedzicha reported, “the number of patients in this subgroup was quite small.”
In another FLAME post hoc analysis, the odds ratio (OR) for exacerbations among the 1,893 patients (56.3%) who were on ICS at study entry was found to be almost identical to the OR among those who were not. Specifically, the ORs for all exacerbations and moderate to severe exacerbations were 0.88 (P = .008) and 0.86 (P = .018), respectively, for those previously treated with ICS and 0.88 (P = .021) and 0.78 (P = .002), respectively, for those who had not been treated with ICS.
The LABA/LAMA combination was also superior to LABA/ICS for improvements in quality of life, which was measured via the St. George’s Respiratory Questionnaire. With an improvement of at least four units on the St. George’s Respiratory Questionnaire defined as clinically meaningful, 49.5% of LABA/LAMA patients versus 43.8% of LABA/ICS patients (P less than .024) benefited on this measure.