Conclusion
The extent of structural damage to the lungs of CF patients is correlated with the response in ppFEV1 on ivacaftor, however this correlation was not demonstrable in patients starting on lumacaftor/ivacaftor. It would take a larger drug effect size and/or larger sample size to see if this correlation also stands after correction for baseline ppFEV1. Brody score derived from chest CT in CF patients correlates with ppFEV1 before the start of CFTR modulating treatment.