Evaluation of the Impact of Elexacaftor/Tezacaftor/Ivacaftor on Aerobic Capacity in Children With Cystic Fibrosis Aged 6-11 Years: Actual Observations and Clinical Perspectives.

Abstract

Background: Cystic fibrosis causes exercise limitation due to impaired lung function and other complications, which in turn increases the chance of mortality. CFTR modulators, particularly the elexacaftor/tezacaftor/ivacaftor (ETI) combination, improve lung function in children older than 6 years in real-life studies.

Objective: This study aimed to assess the impact of ETI on aerobic capacity in children with CF aged 6-11 years under real-life conditions and to evaluate whether prior CFTR modulator treatment affects these outcomes.

Methods: A multicenter, prospective cohort study was conducted with pediatric CF patients. Participants underwent evaluations 6-8 months before ETI (T1), at the start of ETI (T2), and 6-8 months post-treatment (T3). Primary outcomes included cardiorespiratory fitness assessed via peak oxygen consumption (VO₂peak) during a cardiopulmonary exercise test (CPET), and secondary outcomes encompassed lung function, quality of life, physical activity, and functional mobility.

Results: Of the 28 patients (mean age 9.02±1.59 years), 19 were ETI-naive, and 9 had prior CFTR modulator treatment. Significant improvements were observed in FEV₁ (p<0.001), and several functional mobility tests (30CST, Stair Climb Test, 10MWT). However, VO₂peak showed no significant changes between T1 and T3. Quality of life scores improved notably in emotional, eating, and respiratory domains, and a slight improvement was noted in physical activity levels (p=0.037).

Conclusions: ETI treatment significantly enhances lung function and certain aspects of quality of life and physical fitness in pediatric CF patients. However, it does not significantly alter aerobic capacity (VO₂peak) within the observed period.