Abnormal Glucose Tolerance

The investigators are conducting a pilot open-label pre/post interventional trial in adolescents and adults with cystic fibrosis (CF) and abnormal glucose tolerance or early CF-related diabetes mellitus (CFRD) to assess the safety and efficacy of verapamil on beta cell function and dysglycemia.

Diabetes is a major co-morbidity in pancreatic insufficient cystic fibrosis (PI-CF) and associated with worse outcomes. While reduced β-cell mass contributes to the insulin secretory defects that characterizes cystic fibrosis-related diabetes (CFRD), other modifiable determinants appear operative in the emergence and progression of abnormal glucose tolerance towards diabetes. Identifying interventions to preserve β-cell function are crucial for delaying and potentially preventing CFRD development. In this study, we hypothesize that weekly administration of the long-acting glucagon-like peptide-1 (GLP-1) agonist dulaglutide will improve defective early-phase insulin secretion and improve glucose tolerance during a mixed-meal tolerance test.