The triple combination CFTR modulator of elexacaftor, tezacaftor, ivacaftor (ETI, marketed as TrikaftaR or KaftrioR) has produced significant health improvements in people with CF that have one or two copies of the Phe508del variant (Heijerman et al., 2019; Middleton et al., 2019). The gene discussed is CFTR; the disease is cystic fibrosis.