A new highly effective CFTR modulator, elexacaftor-tezacaftor-ivacaftor (ETI), is now available to up to 90% of the CF population and has been shown to increase BMI in adolescents and adults with CF by 0.9–1.1 kg/m2 in phase III clinical trials [43,44]. Here, CFTR is linked to cystic fibrosis.