Short term effects of liraglutide versus vildagliptin on insulin secretion and sensitivity in type 2 diabetes (Liravis study)

Abstract

Introduction : incretinomimetics are new type 2 diabetes mellitus drugs that have the ability to increase glucose-induced insulin production. This drug class has two subclasses: Exogenous Glucagon-Like Peptide analogs (GLP1a) such as Liraglutide, and the inhibitors of Dipeptidyl peptidase IV (DPP4i) that prolong the half-life of endogenous GLP1 such as vildagliptin.We aimed to evaluate the short term metabolic effects of a GLP-1a, liraglutide versus a DPP-4i, vildagliptin on type 2 diabetes patients. Methods : we conducted a randomized controlled single blind clinical trial on 14 uncontrolled type 2 diabetes patients (HbA1c ≥ 53mmol/mol). Participants were randomly allocated in 2 groups. Anthropometric measurements, hyperinsulinemic-euglycemic clamp at 80mU/m 2 /min and a mixed meal tolerance test (to assess insulin sensitivity/secretion) were carried out before and after the different interventions. In group 1, 0.6mg/day of liraglutide was administered subcutaneously and increased to 1.2mg the 2nd week whereas, 100mg/day of oral vildagliptin was administered in group 2 for 2 weeks. Results : after the intervention insulin sensitivity remained unchanged: liraglutide (6.6 [4.2-7.9] to 6.9 [4.3-10.8] mg/kg/min; p=0.61) and vildagliptin (7.1 [5.3- 9.0] to 6.5 [5.6-9.4] mg/kg/min; p = 0.86). LDL Cholesterol levels decreased significantly in group 1(0.85 [0.51-1.02] to 0.54 [0.50-0.73] g/L, p=0.04) but not in group 2 (p= 0.23). Concerning insulin secretion, the area under the C-peptide curve varied from (5.5[1.0-10.9] to 14.9 [10.8-17.2] nmol/L/120min, p=0.09) in group 1 and from 1.1 [0.5-14.1] to 13.0 [9.6-16.9] nmol/L/120min, p=0.17) in group 2, showing a non-significant trend towards improvement. A variation in body weight was remarked amongst the groups, being, - 0.6kg and +1.1kg in group 1 and 2 respectively. Conclusion : there are no significant differences on insulin sensitivity and insulin secretion after two weeks of treatment using liraglutide and vildagliptin, in type 2 diabetes mellitus patients.