Progress in therapies for cystic fibrosis.

Standard follow-up and symptomatic treatment have allowed most patients with cystic fibrosis to live to young adulthood. However, many patients still die prematurely from respiratory insufficiency. Hence, further investigations to improve these therapies are important and might have relevance for other diseases-eg, exploring how to increase airway hydration, how to safely downscale the increased inflammatory response in the lung, and how to better combat lung infections associated with cystic fibrosis. In parallel, development of modulators that target the underlying dysfunction in the cystic fibrosis transmembrane conductance regulator (CFTR) is fast moving forward. Existing treatments are specific to certain mutations, or mutation class, in CFTR. An effective, although not yet entirely corrective, treatment is available for patients with class III mutations, and a treatment with modest effectiveness is available for patients who are homozygous for Phe508del, albeit at a very high cost. Corrective treatments that are non-specific to mutation class and thus applicable to all patients-eg, gene therapy, cell-based therapies, and activation of alternative ion channels that bypass CFTR-are being explored, but they are still in early stages of development. In view of the large number of patients with very rare mutations, a plan to advance personalised biomarkers to predict treatment effect is also being investigated and validated.