Comparison between vildagliptin and metformin to sustain reductions in HbA1c over 1 year in drug-naïve patients with Type 2 diabetes

Abstract

Aims: To evaluate the ability of vildagliptin and metformin to sustain reductions in HbA1c over a 1-year treatment period in drug-naïve patients with Type 2 diabetes (Type 2 DM). Methods: Double-blind, randomized, multicentre, active-controlled, parallel-group study of 52-week treatment with vildagliptin (100 mg daily, n = 526) or metformin (titrated to 2000 mg daily, n = 254) in drug-naïve patients (baseline HbA1c = 7.5-11.0%). HbA1c was measured periodically over 1 year. Results: Vildagliptin and metformin each rapidly decreased HbA1c from an equal baseline of 8.7%. Most of the HbA1c reduction was attained by week 12, and the efficacy was sustained throughout 1-year treatment with both agents. At the study end, significant HbA1c reductions from baseline were seen with both vildagliptin (-1.0 ± 0.1%, P < 0.001) and metformin (-1.4 ± 0.1%, P < 0.001); however, statistical non-inferiority of 50 mg vildagliptin twice daily to 1000 mg metformin twice daily was not established. Body weight did not change during the 1-year treatment with vildagliptin (0.3 ± 0.2 kg, P = 0.17) and decreased in metformin-treated patients (-1.9 ± 0.3 kg, P < 0.001). The proportion of patients experiencing an adverse event was 70.1 vs. 75.4% in patients receiving vildagliptin and metformin, respectively. The proportion of patients experiencing a gastrointestinal adverse event was twofold higher in the metformin group, driven by a 3-4-fold greater incidence of diarrhoea, nausea and abdominal pain. The incidence of hypoglycaemia was similarly low in both groups (< 1%). Conclusions: A clinically meaningful decrease in HbA1c that was sustained throughout a 1-year treatment in drug-naïve patients with Type 2 DM was seen with both metformin and vildagliptin monotherapy. © 2007 Novartis.