The latest combination of elexacaftor, tezacaftor, and ivacaftor (ETI or TRIKAFTA) combines 2 correctors (ET) and a potentiator (I), producing remarkable improvements in lung function in many, but not all, CF patients carrying at least one copy of the most common CFTR mutation, F508del (2–4). This evidence concerns the gene CFTR and cystic fibrosis.