Sun, X. et al. Sci. Transl. Med. 11, eaau7531 (2019)

Although evidence suggests that cystic fibrosis (CF) — a multiorgan disease caused by mutations in the gene encoding cystic fibrosis transmembrane conductance regulator (CFTR) — starts in utero, the long-term effects of in utero abnormalities on the pathology of CF remain unclear. VX-770 (ivacaftor) is a CFTR potentiator that rescues channel gating in dysfunctional CTFR proteins from patients carrying a CFTRG551D mutation. The results of a new study showing that in utero administration of VX-770 in CFTRG551D ferrets protects the animals from developmental abnormalities and neonatal mortalilty associated with CF suggest that early interventions could improve the treatment of CF. The study also offers a new model to understand the role of CFTR in CF pathophysiology and inform future therapies.