Comparative effectiveness of inhaled fluticasone propionate/salmeterol and budesonide/formoterol fixed-dose...

Asthma affects over 260 million people globally, with significant health impacts. The Global Initiative for Asthma (GINA) 2024 report recommends inhaled corticosteroid/long-acting β₂-agonist (ICS/LABA) combinations, including fluticasone propionate/salmeterol (FP/SAL) and budesonide/formoterol (BUD/FOR), for maintenance treatment. Both combinations have demonstrated clinical benefits, with previous clinical trials and real-world studies showing comparable asthma control with FP/SAL and BUD/FOR. This United States (US)-based study compares the real-world effectiveness of FP/SAL and BUD/FOR on asthma control and treatment adherence.

This retrospective cohort study analyzed data from the US Optum's Market Clarity database (July 1, 2010, to December 31, 2019), with integrated medical, pharmacy claims, and clinical electronic health records. Patients aged ≥18 years with asthma at GINA Steps 3-4, and ≥1 pharmacy claim for FP/SAL or BUD/FOR (index) were included. Patients on other ICS/LABA therapy ≥12 months prior to index were excluded. Inverse probability of treatment weighting adjusted for confounders. Outcomes were stratified by asthma severity.

A total of 57,000 patients were included (FP/SAL: 28,639; BUD/FOR: 28,361). Baseline characteristics were balanced post-weighting. Asthma control was similar between cohorts, with no significant differences in Asthma Control Test scores or short-acting β₂-agonist fills during the 12-month period following the index. Treatment adherence, assessed using proportion of days covered (≥0.8), was higher in the FP/SAL cohort (5.4 %) versus the BUD/FOR cohort (4.4 %; p < 0.001).

FP/SAL and BUD/FOR were similarly effective for asthma control in real-world settings, while FP/SAL was generally associated with greater medication adherence, a key factor for long-term control.