Time-to-first exacerbation, adherence, and medical costs among US patients receiving umeclidinium/vilanterol or tiotropium as initial maintenance therapy for chronic obstructive pulmonary disease: a retrospective cohort study

Background Adherence to chronic obstructive pulmonary disease (COPD) maintenance medication is important for managing symptoms and exacerbation risk, and is associated with reduced mortality, hospitalizations, and costs. This study compared on-treatment exacerbations, medical costs, and medication adherence in patients with COPD initiating treatment with umeclidinium/vilanterol (UMEC/VI) or tiotropium (TIO). Methods This retrospective matched cohort study selected patients from Optum’s de-identified Clinformatics Data Mart database who initiated maintenance treatment with UMEC/VI or TIO between 01/01/2014 and 12/31/2017 (index date defined as the first dispensing). Eligible patients were ≥ 40 years of age and had ≥ 12 months continuous health plan coverage pre- and post-index; ≥ 1 medical claim for COPD pre-index or on the index date; no moderate/severe COPD-related exacerbations on the index date; no asthma diagnosis pre- or post-index; no maintenance medication fills containing inhaled corticosteroids, long-acting β2-agonists, or long-acting muscarinic antagonists pre-index or on the index date; and no fills for both UMEC/VI and TIO on the index date. Outcomes included time-to-first (Kaplan–Meier analysis) and rates of on-treatment COPD-related moderate/severe exacerbations, medication adherence (proportion of days covered [PDC] and proportion of adherent patients [PDC ≥ 0.8]), and COPD-related medical costs per patient per month (PPPM). Propensity score matching was used to adjust for potential confounders. Results Each cohort included 3929 matched patients. Kaplan–Meier rates of on-treatment COPD-related exacerbations were similar between cohorts (hazard ratio at 12 months; overall: 0.93, moderate: 0.92, severe: 1.07; all p > 0.05). UMEC/VI versus TIO initiators had significantly higher adherence (mean PDC: 0.44 vs 0.37; p < 0.001; proportion with PDC ≥ 0.8: 22.0% vs 16.4%; p< 0.001) and significantly lower mean on-treatment COPD-related total medical costs ($867 vs $1095 PPPM; p = 0.028), driven by lower outpatient visit costs. Conclusions These findings provide valuable information for physicians considering UMEC/VI or TIO as initial maintenance therapy options for patients with COPD.