CFTR and cystic fibrosis: To overcome this problem, combination of modulators (correctors and potentiators) of this channel, which may be considered as pharmacoperone drugs, have been succesfully administered to patients with cystic fibrosis bearing the ΔF508 CFTR mutation (25, 27, 30, 240–246), resulting in a significant improvement on some primary and secondary end points (30, 242).