Comparison of vildagliptin and metformin monotherapy in elderly patients with type 2 diabetes: a 24-week, double-blind, randomized trial

Aims: The study evaluated the efficacy and tolerability of the dipeptidyl peptidase‐4 inhibitor, vildagliptin, and metformin in drug‐naïve elderly patients with type 2 diabetes. The primary objective was to demonstrate non‐inferiority of vildagliptin vs. metformin in glycated haemoglobin (HbA_1c) reduction. Methods: This was a double‐blind, randomized, multicentre, active‐controlled, parallel‐group study of 24‐week treatment with vildagliptin (100 mg daily, n = 169) or metformin (titrated to 1500 mg daily, n = 166) in drug‐naïve patients with type 2 diabetes aged ≥65 years (baseline HbA_1c 7–9%). Results: Participants had a mean age of 71 years, known duration of diabetes of 3 years and mean baseline HbA_1c of 7.7%. At end‐point, vildagliptin was as effective as metformin, improving HbA_1c by ?0.64 ± 0.07% and ?0.75 ± 0.07%, respectively, meeting the predefined statistical criterion for non‐inferiority (upper limit of 95% confidence interval for between‐treatment difference ≤0.3%). Body weight changes were ?0.45 ± 0.20 kg in vildagliptin‐treated patients (p = 0.02) and ?1.25 ± 0.19 kg in metformin‐treated patients (p < 0.001; p = 0.004 vs. vildagliptin). The proportion of patients experiencing an adverse event (AE) was 44.3 vs. 50.3% in patients receiving vildagliptin and metformin respectively. Gastrointestinal (GI) AEs were significantly more frequent with metformin (24.8%) than with vildagliptin (15.0%, p = 0.028), mainly driven by a 4.4‐fold higher incidence of diarrhoea. A low incidence of hypoglycaemia was observed in both treatment groups (0% with vildagliptin and 1.2% with metformin). Conclusions: Vildagliptin is an effective and well‐tolerated treatment option in elderly patients with type 2 diabetes, demonstrating similar improvement in glycaemic control as metformin, with superior GI tolerability.