Discovery heralds new approach to the treatment of cystic fibrosis.

C fibrosis (CF) is a lethal obstructive airways disease that afflicts more than 80 000 patients worldwide. The cause of CF was elucidated in 1989 by the cloning of the gene for the CF transmembrane conductance regulator (CFTR), which controls chloride and bicarbonate transport across epithelial membranes in multiple organs such as the lung and GI tract. There are over 1900 known mutations in the CFTR gene, which compromise its function and lead to a buildup of mucus, airway obstruction, and the growth of pathogenic bacteria. In this issue, a team from Vertex reports the discovery of the first small molecule potentiator for one of the mutant CFTRs, heralding a new era in the treatment of CF. When CF was first comprehensively described as a disease in the late 1930s, life expectancy was only a year or two for CF patients. The introduction of antibiotics following World War II, and especially Gram negative antibiotics in the 1960s, saw this increase into the teens (Figure 1). When the CF gene was