Aims: To evaluate the efficacy and safety of two dosage strengths of a single-tablet metformin-glibenclamide (glyburide) combination, compared with the respective monotherapies, in patients with Type 2 diabetes mellitus (DM) inadequately controlled by metformin monotherapy.
Methods: In this 16-week, double-blind, multicentre, parallel-group trial, 411 patients were randomized to receive metformin 500 mg, glibenclamide 5 mg, metformin-glibenclamide 500 mg/2.5 mg or metformin-glibenclamide 500 mg/5 mg, titrated with the intention to achieve fasting plasma glucose (FPG) < or = 7 mmol/l.
Results: Decreases in glycated haemoglobin (HbA1c) and FPG were greater (P < 0.05) for metformin-glibenclamide 500 mg/2.5 mg (-1.20% and -2.62 mmol/l) and 500 mg/5 mg (-0.91% and -2.34 mmol/l), compared with metformin (-0.19% and -0.57 mmol/l) or glibenclamide (-0.33% and -0.73 mmol/l). HbA1c < 7% was achieved by 75% and 64% of patients receiving metformin-glibenclamide 500 mg/2.5 mg and 500 mg/5 mg, respectively, compared with 42% for glibenclamide and 38% for metformin (P = 0.001). These benefits were achieved at lower mean doses of metformin or glibenclamide with metformin-glibenclamide 500 mg/2.5 mg and 500 mg/5 mg (1225 mg/6.1 mg and 1170 mg/11.7 mg) than with glibenclamide (13.4 mg) or metformin (1660 mg). Treatment-related serious adverse events occurred in two patients receiving glibenclamide. Plasma lipid profiles were unaffected and mean changes in body weight were < or = 1.0 kg.
Conclusions: Intensive management of Type 2 DM with a new metformin-glibenclamide combination tablet improved glycaemic control and facilitated the attainment of glycaemic targets at lower doses of metformin or glibenclamide compared with the respective monotherapies, without compromising tolerability.