CFTR and gallstones: A potential mechanism by which ELX/TEV/IVA (or other CFTR modulators) may trigger biliary colic was hypothesized by Safirstein et al. [53]; restoring CFTR function in the biliary epithelium will cause changes in the fluidity and acidity of bile fluids, which may result in mobilization of existing gallstones and precipitation of biliary colic.