Liraglutide is effective in type 2 diabetic patients with sustained endogenous insulin-secreting capacity

Aims/Introduction: Recently, glucagon-like peptide-1 (GLP-1) receptor agonists of liraglutide have become available in Japan. It has not yet been clarified what clinical parameters could discriminate liraglutide-effective patients from liraglutide-ineffective patients. Materials and Methods: We reviewed 23 consecutive patients with type 2 diabetes admitted to Osaka University Hospital for glycemic control. All of the patients were treated with diet plus insulin (or plus oral antidiabetic drugs) to improve fasting plasma glucose (FPG) and postprandial glucose below 150 and 200 mg/dL, respectively. After insulin secretion and insulin resistance were evaluated, insulin was replaced by liraglutide. The efficacy of liraglutide was determined according to whether glycemic control was maintained at the target levels. Results: Liraglutide was effective in 13 of 23 patients. There were significant differences in the parameters of insulin secretion, including fasting C-peptide (F-CPR), C-peptide index (CPI), insulinogenic index (I.I.) and urine C-peptide (U-CPR), between liraglutide-effective and -ineffective patients. The duration of diabetes was significantly shorter in liraglutide-effective patients than in liraglutide-ineffective patients. In receiver operating characteristic analyses, the cut-off value for predicting the efficacy of liraglutide was 0.14 for I.I., 1.1 for CPI, 1.5 ng/mL for F-CPR, 33.3 mu g/day for U-CPR and 19.5 years for duration of type 2 diabetes. Conclusions: Insulin secretion evaluated by F-CPR, CPI, I.I., U-CPR and the duration of type 2 diabetes were useful parameters for predicting the efficacy of liraglutide in patients with type 2 diabetes. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2011.00168.x, 2011)