INS and cystic fibrosis-related diabetes: Lumacaftor/Ivacaftor imrpoved glucose tolerance in a significant proportion of CF patients. The improvement in glucose metabolism was not associated with increased insulin secretion, suggesting an indirect effect rather than a direct impact on pancreatic β-cell function. The beneficial metabolic effects may be related to improvements in overall nutritional and respiratory status rather than a direct action on CFTR function in β-cells. Larger and randomized trials are needed to further investigate the role of CTFR modulators in glucose metabolism and CFRD prevention.