The development of radically new treatments for cystic fibrosis (CF) proceeds apace. In February 2018 Archivist reported on trials of double-modulator therapies (tezacaftor-ivacaftor) that produced modest benefits (doi:10.1136/archdischild-2017–3 14 602). Adding a third agent could, in theory, further enhance the intracellular functioning of the defective CFTR protein by binding to different sites on the molecule, particularly in those with the most common Phe508del mutation. Two such agents which showed promise in vitro were used in ….... To read the full article, log in using your NHS OpenAthens details.