Safety and Efficacy of Switching Patients With Type 2 Diabetes From Glucagon-Like Peptide-1 Receptor Agonists to Tirzepatide: A Case Series.

Tirzepatide is a novel glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist (RA) that is approved for the treatment of type 2 diabetes mellitus (T2D). Despite its similarities to GLP-1 RA, there is a lack of data on how to switch between GLP-1 RA and GIP/GLP-1 RA. The objective of this study is to evaluate the efficacy and safety of switching from GLP-1 RA to tirzepatide in patients with T2D and provide guidance for switching between the two classes. This was a retrospective case series of patients with T2D who met protocol criteria for switching between the two classes. Hemoglobin A1C (A1C) and weight data were evaluated at 3 and 6 months. A total of 10 patients were included. Mean change from baseline in A1C was -0.7 ± 0.9% at 3 months (N = 8) compared to -1.4 ± 0.7% at 6 months (N = 4). Percentage of patients who achieved their goal A1C was 25% (2/8) at 3 months post switch compared to 50% (2/4) at 6 months. Mean change from baseline in weight was -3.6 ± 2.3 kg at 3 months and -6 ± 3.4 kg at 6 months. Percentage of patients who achieved weight loss from baseline of ≥10% was 0 at 3 months versus 33.3% (1/3) at 6 months. Few adverse events were reported after switching. Switching can be considered for patients with T2D that require further A1C and weight reduction to reach their target goals despite being on GLP-1 RA.