Impact of single-inhaler triple therapy on COPD treatment in the period from 2016–2022: A nationwide Danish cohort study

<bold>Background:</bold> In July 2017, the first single-inhaler triple therapy (SITT) with combined inhaled corticosteroid (ICS), long-acting beta-2-agonist (LABA), and long-acting muscarinic receptor antagonist (LAMA) for treatment of chronic obstructive pulmonary disease (COPD) was introduced. This study investigated the impact of SITT by assessing patient characteristics, prescription patterns, prescriber segment and adherence among patients with COPD in the general population. <bold>Methods:</bold> We included 30,442 patients aged ≥40 years with a diagnosis of COPD recorded in the national Danish Patient Register. We compared SITT and multiple-inhaler triple therapy (MITT) and analysed changes in incidence, prescription patterns over time and adherence in the two groups. <bold>Results:</bold> The incidence of MITT declined from 43% to 12% between 2016-2022, while SITT has increased to 47%. The prevalence of triple treatment overall was constant over the period 46.5±1.5%. Among those initiating SITT, 36% came from no treatment, 30% from dual, 28% from MITT, and 6% from mono treatment. SITT showed greater adherence: 85% of patients on SITT had high adherence (>80% of days covered) vs. 56% on MITT, while low adherence (<50%) was more common in MITT: 23% for MITT vs. only 4% for SITT. <bold>Conclusion:</bold> The introduction of SITT for COPD has led to a decline in MITT use and an increase in SITT prescriptions over time, with better adherence observed in patients on SITT compared to MITT. These findings suggest that fixed triple therapy optimises patient adherence and enhances COPD management.