Cystic fibrosis transmembrane conductance regulator modulators for cystic fibrosis: a new dawn?

Abstract

Cystic fibrosis (CF) is the most common life-limiting inherited condition in Caucasians. It is a multisystem autosomal recessive disorder caused by variants in the gene for cystic fibrosis transmembrane conductance regulator (CFTR) protein, a cell-surface localised chloride channel that regulates absorption and secretion of salt and water across epithelia. Until recently, the treatment for CF was predicated on ameliorating and preventing the downstream symptoms of CFTR dysfunction, primarily recurrent respiratory infections and pancreatic exocrine failure. But a new class of therapy—the CFTR modulators, which treat the basic defect and decrease the complications of CF, leads to significantly improved pulmonary function, decreased respiratory infections and improved nutrition. The newest agent, a combination of elexacaftor, tezacaftor and ivacaftor, will be suitable for approximately 90% of all people with CF and is likely to decrease the morbidity and significantly increase the life expectancy for most people with CF. The major barrier to their widespread introduction has been their cost, with many countries unwilling or unable to fund them. Nevertheless, such is their therapeutic efficacy and their likely potent effect on life expectancy that their advent has wider societal implications for the care of children and adults with CF.