Efficacy of switching from dipeptidyl peptidase-4 inhibitors to dulaglutide in patients with type 2 diabetes

Background: Several reports showed that the effects of daily Glucagon-like peptidase-1 (GLP-1) receptor agonists for lowering plasma glucose and body weight are superior to those of dipeptidyl peptidase-4 (DPP-4) inhibitors, while the superiority of weekly GLP-1 receptor agonists, dulaglutide, is still unclear. The aim of this study was to evaluate the efficacy of dulaglutide therapy switching from DPP-4 inhibitors in patients with type 2 diabetes. Methods: We retrospectively evaluated the 79 Japanese patients with type 2 diabetes at the Diabetes Outpatient Clinic in Tomakomai City Hospital whose treatment was switched from DPP-4 inhibitors to dulaglutide. We investigated the change of hemoglobin A1c (HbA1c), casual plasma glucose (CPG) levels and body weight 4 weeks, 8 weeks and 12 weeks after switching from DPP-4 inhibitors to dulaglutide. In addition, we defined the group in which HbA1c was improved more than 1% as “improved group” (n = 37) and the group in which HbA1c was improved less than 1% as “non-improved group” (n = 42), and compared the patients’ background in both the groups. The subtraction of HbA1c at each weeks and baseline HbA1c was defined as ⊿HbA1c. Results: After switching to dulaglutide, HbA1c showed a significant decrease from 4 weeks later, and the effect was maintained even after 12 weeks. The “improved group” had lower estimated glomerular filtration rate (eGFR) and higher baseline HbA1c than the “non-improved group”. In the “improved group”, ⊿HbA1c showed a significant correlation with eGFR and baseline HbA1c. Conclusion: Switching from DPP-4 inhibitors to dulaglutide could improve HbA1c, especially in cases with low eGFR and high HbA1c.