Introduction: Management of post-transplant diabetes mellitus is challenging; there is a lack of prospective randomized controlled trials for safety and efficacy of antidiabetic medications in solid organ recipients. Glucagon-like peptide 1 receptor agonists (GLP-1RA) are a relatively new class of medications used to manage type 2 diabetes in the general population. They have several benefits besides glycemic control, including weight loss and improved cardiovascular risk. However, they have not been studied extensively in the post-transplant population for safety and efficacy.

Methods: We conducted a retrospective study of patients who had received kidney, liver, or heart transplant, had diabetes either pre- or post-transplant, and were treated with GLP-1RA. We identified seven kidney, seven liver, and five heart transplant recipients who had received GLP-1RA. We assessed changes in immunosuppressant levels, rejection episodes, changes in hemoglobin A1c (HbA1c), weight, and body mass index (BMI) while on the GLP-1RA. We also looked at changes in insulin dose, other diabetes medications, heart rate, blood pressure, and renal function.

Results: After a mean follow-up period of 12 months, there were no significant changes in tacrolimus (FK506) levels and renal function for the period of GLP-1RA use. At the end of 12 months, the mean drop in weight was 4.86 kg [95% CI - 7.79, - 1.93]. The BMI decreased by a mean of 1.63 kg/m² at the end of 12 months [95% CI - 2.53, - 0.73]. HbA1c decreased from baseline by 1.08% [95% CI - 1.65, - 0.51], 0.96% [95% CI - 1.68, - 0.25], and 0.75% [95% CI - 1.55, 0.05] at 3, 6, and 12 months, respectively.

Conclusions: Our data suggest that GLP-1RA do not affect tacrolimus levels or transplant outcomes in solid organ transplant (SOT) recipients in the short term. GLP-1RA also seem to be as effective in SOT recipients for glycemic control and weight loss as in the non-transplant population with diabetes.