Impact of elexacaftor/tezacaftor/ivacaftor on the small airways in cystic fibrosis.

Objective: To evaluate the impact of the elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) combination on the small airways in adults with cystic fibrosis (CF), a genetic disorder that primarily affects the respiratory system, leading to progressive lung disease. In CF, the small airways play a critical role, contributing to chronic symptoms such as cough, sputum production, and dyspnea.

Methods: This was a single-center, retrospective observational study of adults with CF treated with ELX/TEZ/IVA for 12 months. We compared the patients who were homozygous for the F508del mutation of the CF transmembrane conductance regulator (CFTR) gene with those who were heterozygous for that mutation, in terms of lung function outcomes (FEV1, FEF25-75%, and the RV/TLC ratio) and the extent of non-homogeneous ground-glass opacity. Among the patients within the cohort, the same parameters were evaluated separately in those who had advanced lung disease and in those who had previously undergone CFTR modulator therapy.

Results: There was a significant post-treatment improvement in lung function, with a median increase of 0.42 L/s in the FEF25-75% (p < 0.001) and a 5% reduction in the mean RV/TLC ratio (p < 0.001). There was a trend toward a higher improvement the F508del homozygous patients. A significant reduction in non-homogeneous ground-glass opacity was observed in 79.5% of the patients. Among the patients with advanced lung disease, there were notable post-treatment improvements in all of the parameters assessed.

Conclusions: Our results highlight the positive impact that ELX/TEZ/IVA treatment can have on small airway function in patients with CF, with potential benefits even for those with advanced lung disease. Further research is needed in order to evaluate the long-term effects of this treatment and its relationship with patient-reported outcomes.