Glucagon-Like Peptide-1 Receptor Agonists: Their Therapeutic Potential in Cystic Fibrosis

Cystic fibrosis (CF) is a monogenic disorder leading to pulmonary disease, pancreatic insufficiency and cystic fibrosis-related diabetes (CFRD). Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are now being investigated in people with cystic fibrosis (pwCF) and CFRD. To date, their therapeutic potential has been almost exclusively studied in case reports or case series. These agents improved glycated haemoglobin (HbA_1c) and continuous glucose monitoring (CGM) parameters. Benefits were also observed in weight reduction, particularly for subjects on cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapy elexacaftor/tezacaftor/ivacaftor (ETI). However, discordant results have also been reported. Moreover, GLP-1RAs have improved pulmonary function, even following lung transplantation. Importantly, the dual glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptor agonist tirzepatide has also yielded favourable outcomes. Finally, preliminary evidence suggests potential inhibition of bone resorption, pointing to a therapeutic perspective in cystic fibrosis-related bone disease (CFBD). However, potential adverse events should not be ignored. These include risk of acute pancreatitis, nausea/vomiting, nutritional depletion, bowel dysmotility and distal intestinal obstruction syndrome, as well as others. Adverse events should be addressed with caution, and dose adjustments may be useful. Large prospective multicentre studies are now required to validate these outcomes and to suggest implications for clinical practice.