Sitagliptin demonstrated both renal and glycemic benefits when used as add-on therapy in adolescents with type 1 diabetes mellitus (T1DM) and diabetic nephropathy. A randomized controlled trial presented at the 51st Annual Conference of the International Society for Pediatric and Adolescent Diabetes (ISPAD) evaluated the impact of dipeptidyl peptidase-4 (DPP-4) inhibition in combination with AHCL therapy.

The study enrolled 46 adolescents with T1DM and nephropathy who were randomized to receive sitagliptin 50 mg daily for 3 months in addition to AHCL therapy or AHCL therapy alone. Baseline clinical characteristics, laboratory parameters, and system settings were comparable between groups (p > 0.05). Serum SDF-1 levels were significantly higher in all T1DM participants compared with healthy controls (p < 0.001).

After 3 months, sitagliptin significantly reduced SDF-1 levels from 3.58 ± 0.73 to 1.99 ± 0.76 ng/mL (p < 0.001) and improved UACR from 7.27 ± 2.41 to 1.32 ± 0.31 mg/mmol (p < 0.001). Sitagliptin also reduced postprandial glucose, sensor glucose, coefficient of variation, and total daily insulin dose. TIR 70–180 mg/dL and insulin-to-carbohydrate ratio increased significantly. No severe hypoglycemia or DKA was reported.

These findings indicate that adding sitagliptin to AHCL therapy improves renal markers and glycemic stability without safety concerns.