Ion channel regulators for the treatment of cystic fibrosis

Abstract

Cystic fibrosis is a life-shortening hereditary disease caused by mutations in the cystic fibrosis transmembrane conductance regulator gene. The main clinical manifestations are chronic infections of the airways, malabsorption due to pancreatic insufficiency, male infertility and salt loss syndromes. The cystic fibrosis transmembrane conductance regulator protein functions as a chloride channel in the apical cell membrane and is thought to inhibit the epithelial sodium channel. In the lung, absence or dysfunction of the cystic fibrosis transmembrane conductance regulator protein leads to dehydration of the airway surface liquid and disturbed mucociliary clearance. After decades of symptomatic therapy to combat the relentless disease progression, there is now hope that interference with the apical ion channel functions will bring a major improvement in the disease course. We discuss the ion channel regulators currently under clinical evaluation in cystic fibrosis, as well as some of the challenges associated with finding disease-modifying therapies. In this article we give a brief description of the clinical and epidemiological aspects of the disease cystic fibrosis. We discuss the pathophysiology of cystic fibrosis, the ion channel regulators under clinical development as potential disease-modifying therapies and some of the challenges associated with developing groundbreaking therapies for this orphan disease.