Repaglinide is more efficient than glimepiride on insulin secretion and post-prandial glucose excursions in patients with type 2 diabetes. A short term study

Objectives: To compare the effect of Repaglinide (R) vs Glimepiride (G) on glucose- and meal-induced insulin secretion and on meal-test induced postprandial glucose excursions. Methods: After 2 weeks washout period, a 3-month randomised, cross-over parallel group trial of R (1 mg x 2/die) vs G (2 mg/die) in 14 patients with type 2 diabetes "naive" in diet treatment was made. Results: Both R and G significantly but similarly lowered fasting glucose levels and improved fasting plasma insulin levels vs baseline. Hyperglycemic clamp showed that both 1(st) (129.15 +/- 23.6 vs 106.90 +/- 18.6 pmol/L; p = 0.01) and 2(nd) phase (189.42 +/- 34.4 vs 144.21 +/- 37.3 pmol/L; p = 0.003) P-cell response to glucose as well as area under the curve (52.07 +/- 10.86 vs 39.54 +/- 10.27 mumol/L x 120'; p = 0.005) were greater in R than G groups. Insulin action (4.0 +/- 1.1 vs 3.2 +/- 0.9 mg x Kg x 60'/muU/mL; p = 0.046) was also improved by R than G administration. In the meal test, R therapy produced a more rapid induction of insulin secretion during the first part. In fact, the mean rise in insulin secretion peaked at 45 min in R (p = 0.001 vs G) and at 60 min in G (p = 0.001 vs R). Consequently, glucose spike at 60 min was higher in G group compared to glucose spike at 45 min in R group (p = 0.002). Conclusions: Our study demonstrates that R is more efficient that G on improving glucose- and meal-induced insulin secretion as well as on controlling for postprandial glucose excursion.