[Efficacy and safety of glimepiride plus metformin in a single presentation, as combined therapy, in patients with type 2 diabetes mellitus and secondary failure to glibenclamide, as monotherapy]

Abstract

Objective: To evaluate the efficacy and safety of glimepiride plus metformin in a single presentation, as combined therapy, in patients with type 2 diabetes mellitus (DM2) with secondary failure to glibenclamide.

Material and methods: A randomized, double-blind, multicentric trial was carried out in 104 obese patients with DM2, fasting glucose > 140 mg/dL and glycated hemoglobin A1c (A1C) > 8%, in spite of treatment with glibenclamide at maximum doses and medical nutrition therapy for at least the 3 months previous to the study. After randomization, the patients received in titrated way during 3 months one of the following treatments: up to 4 mg of glimepiride, 2 g of metformin or 4 mg of glimepiride plus 2 g of metformin in a single presentation. Efficacy criteria were either a decrease in A1C of 1% or more, or a reduction in A1C of 7% or less. Adverse events were carefully monitored during the study.

Results: At the end of the study, the decrease in A1C concentration was -0.9 +/- 1.6% (CI 95%: -0.2 to -1.5) in the glimepiride group, -0.7 +/- 2.1% (CI 95%: 0.2 to -1.6) in the metformin group, and -1.3 +/- 1.8 mg/dL (CI 95%: -0.6 to -1.9) in the combined therapy group. The percentage of patients that showed a decrease in AIC of 1% or higher was 35.1, 21.2 and 47.0% in the glimepiride, in the metformin and in the combined therapy groups, respectively (p < 0.001). The percentage of patients with decreased AIC of 7% or less was 18.9, 9.0 and 23.5% in the glimepiride, in the metformin and in the combined therapy groups, respectively (p = 0.01). The frequency of adverse events was similar for all the groups.

Conclusion: The combined use of glimepiride plus metformin in a single presentation for 3 months showed to be efficacious and safe in patients with DM2 and secondary failure to glibenclamide.