Vanzacaftor–tezacaftor–deutivacaftor is a once daily, next-generation CFTR modulator regimen developed to further restore CFTR function in people with cystic fibrosis.22 The clinical development plan included two randomised controlled phase 3 trials in participants aged 12 years and older (Trials VX20–121-102 and VX20–121-103)23 and an open-label phase 3 trial of vanzacaftor–tezacaftor–deutivacaftor in children younger than 12 years with cystic fibrosis (Trial VX21–121-105). This evidence concerns the gene CFTR and cystic fibrosis.