Abstract

Background: Although adding insulin glargine to oral antidiabetic drugs (OADs) has demonstrated efficacy in patients with type 2 diabetes, evidence supporting specific regimens is lacking. The aim of this study was to compare the efficacy of combination therapy of insulin glargine with either sulfonylurea (SU) or metformin (Met) in patients with poorly controlled type 2 diabetes receiving ≥ 2 OADs.

Methods: This was a 48-week prospective, open-label, randomized, parallel trial. Patients with type 2 diabetes poorly controlled with ≥ 2 OADs were randomized to the insulin glargine with Met (Met-group) or insulin glargine with SU (SU-group).

Results: Mean glycosylated hemoglobin (A1C) reduction were significant in the Met-group and SUgroup (-1.42 ± 0.28% and -1.00 ± 0.28%, respectively), but no statistically significant difference between groups (-0.40 ± 0.3%, p = 0.234). There was no difference in the proportion of patients achieving A1C of < 7% (12.8% and 6.8%, respectively). Mean FPG reduced significantly in both groups (-120.3 ± 8.8 mg/dL and -90.2 ± 11.1 mg/dL, respectively), with greater reductions in the Met-group (-34.8 ± 10.0 mg/dL, p < 0.001). More proportions of patients in the Met-group achieved the FPG target of < 130 mg/dL (80.9% and 40.9%, respectively, p < 0.001). The percentages of patients experiencing episodes of symptomatic hypoglycemia (Met-group: 23.4%, SU-group: 19.6%) and the percentages of nocturnal hypoglycemia (Met-group: 8.5%, SU-group: 6.5%) were similar among the two groups.

Conclusion: In patients with type 2 diabetes poorly controlled on ≥ 2 OADs, glycemic control was comparable among the two regimens.