Objectives: Chronic rhinosinusitis is common among patients with cystic fibrosis (CF) and often significantly impacts their quality of life. The introduction of CFTR modulators, particularly the triple therapy of elexacaftor/tezacaftor/ivacaftor (ETI), appears to alleviate these symptoms. This study aims to evaluate the effect of this therapy on children and adolescents under 20 years of age with cystic fibrosis and concurrent chronic rhinosinusitis. Methods: A prospective single-institution study was conducted. Patients were evaluated before starting treatment with ETI and after a median period of 3 months of therapy. Nasal endoscopy findings were recorded using the modified Lund-Kennedy score. Additionally, the Sinonasal Outcome Test-22 (SNOT-22), validated for Greek patients, was administered. Results: A total of 15 patients participated in the study, with a median age of 18 years, ranging from 14 to 20 years. Seven patients (46.7%) were male, and 8 (53.3%) were female. Analysis of the SNOT-22 scores before and after treatment showed no statistically significant difference ( P = .325). However, the analysis of the modified Lund-Kennedy scores revealed a statistically significant improvement after a median period of 3 months of treatment ( P = .002). Conclusion: Patients with cystic fibrosis (CF) often suffer from chronic rhinosinusitis. The highly effective modulator therapy with ETI appears to result in a statistically significant improvement in sinonasal disease as assessed by nasal endoscopy. Conversely, this innovative therapy does not seem to improve the quality of life for CF patients experiencing rhinosinusitis symptoms, likely due to the few preexisting symptoms before initiation of the therapy.

Background: Highly effective CFTR modulator therapy has substantially changed the clinical course of cystic fibrosis (CF), but the magnitude of treatment response may vary according to baseline lung function. We evaluated the real-world effects of elexacaftor/tezacaftor/ivacaftor (ETI) in people with CF aged >6 years across a broad range of baseline lung function. Methods: In this observational study, 62 people with CF (23 male; age range 7.8–36.8 years) who were eligible for ETI according to genotype underwent assessment at treatment initiation and after 6 months. Assessments included spirometry, respiratory oscillometry, body composition and biochemical measurements. Results: Mean ppFEV1 increased from 94% at baseline to 108% after 6 months (p < 0.001), while mean FEF25–75 increased from 77% to 100% predicted (p < 0.001). Lower baseline ppFEV1 was associated with a greater ppFEV1 response (r = −0.596, p < 0.001), and baseline ppFEV1 remained the only significant factor associated with ppFEV1 change in multivariable analysis (β = −0.21, p = 0.006). Improvement was greater among participants with baseline ppFEV1 < 90%, although a measurable increase was also observed in those with ppFEV1 ≥ 90%. BMI increased significantly. HDL and LDL cholesterol increased (p = 0.007 and p = 0.011, respectively), whereas C-reactive protein decreased (p < 0.001). Changes in oscillometry were modest and provided limited additional information beyond spirometry in this cohort. Conclusions: ETI was associated with significant improvements in lung function in people with CF aged >6 years, including those with preserved baseline spirometry. The magnitude of ppFEV1 improvement was greatest in participants with lower baseline ppFEV1. These findings support measurable physiological benefit from ETI across a broad spectrum of baseline lung function, while highlighting the need for longer-term studies of outcomes in people with near-normal spirometry.