CFDB - Cystic Fibrosis DataBase

primary studies published RCT

Effect of Sitagliptin on Islet Function in Pancreatic Insufficient Cystic Fibrosis With Abnormal Glucose Tolerance.

Study design (if review, criteria of inclusion for studies)

Randomized double-blind trial


Twenty-six adults from Children's Hospital of Philadelphia and University of Pennsylvania CF Center with PI-CF and AGT (defined by oral glucose tolerance test glucose [mg/dL]: early glucose intolerance [1-hour ≥155 & 2-hour <140], impaired glucose tolerance [2-hour ≥140 and <200 mg/dl], or diabetes [2-hour ≥200]). 24 completed the trial (n=12 sitagliptin; n=12 placebo).


Patients were randomized to a 6-month double-blind trial of DPP-4 inhibitor sitagliptin 100 mg daily or matched-placebo

Outcome measures

Main outcome measures were mixed-meal tolerance test (MMTT) responses for intact GLP-1 and GIP, insulin secretory rates (ISR), glucagon suppression, and glycemia and glucose-potentiated arginine (GPA) test-derived measures of β- and α-cell function.

Main results

Following 6-months of sitagliptin vs. placebo, MMTT intact GLP-1 and GIP responses increased (P <0.001), ISR dynamics improved (P <0.05), and glucagon suppression was modestly enhanced (P <0.05) while GPA test responses for glucagon were lower. No improvements in glucose tolerance or β-cell sensitivity to glucose, including for second-phase insulin response were found.

Authors' conclusions

In glucose intolerant PI-CF, sitagliptin intervention augmented meal-related incretin responses with improved early insulin secretion and glucagon suppression without affecting post-prandial glycemia.

Keywords: Sitagliptin; Hypoglycemic Agents; pharmacological_intervention; Diabetes Mellitus; Pancreatic Diseases; Gastrointestinal Diseases;