Restoring cystic fibrosis transmembrane conductance regulator function reduces airway bacteria and inflammation in people with cystic fibrosis and chronic lung infections

Ivacaftor is a cystic fibrosis transmembrane receptor (CFTR)-directed treatment for people with cystic fibrosis (CF) and a G551D mutation (approximately 5% of the CF population). Treatment results in significant clinical benefits; however, the effects on the pulmonary microbiome are less well understood. Hisert et al (Am J Respir Crit Care Med 2017;195:1617–28) prospectively studied 12 subjects as they were initiated on ivacaftor. Sputum was collected at multiple times in the first week of treatment and then regularly for over 2 years. Airway inflammatory profile, P. aeruginosa sputum counts, quantitative PCR and changes in the 16S microbiome were all investigated. Rapid and significant reductions in the sputum inflammatory cytokines interleukin (IL)-8, IL-1B and neutrophil elastase were observed during the first week of treatment and continued to decrease over the subsequent 24-month follow-up. P. aeruginosa counts showed a 10-fold reduction (−1.67 log₁₀ CFU/mL, 95% CI −2.39 to −0.96; …