Insulin glulisine compared to insulin aspart and to insulin lispro administered by continuous subcutaneous insulin infusion in patients with type 1 diabetes: a randomized controlled trial

In a previous pilot study comparing insulin glulisine (GLU) with insulin aspart (ASP) administered by continuous subcutaneous insulin infusion (CSII), GLU-treated patients did show a trend toward fewer catheter occlusions compared with ASP-treated patients. Here we performed a randomized open-label, three-way crossover, controlled multicenter study comparing GLU with ASP and insulin lispro (LIS). Subjects with type 1 diabetes were allocated to one of three treatment orders-GLU-ASP-LIS, ASP-LIS-GLU, or LIS-GLU-ASP-with each insulin used for 13 weeks. The study was designed to demonstrate the superiority of GLU over ASP and LIS on unexplained hyperglycemia and/or perceived infusion set occlusion. A prespecified P value of 0.025 was considered significant to correct for multiple testing. Percentages of subjects with at least one unexplained hyperglycemia and/or infusion set occlusion were not significantly different between GLU and ASP (68.4% [62.7-74.1%] vs. 62.1% [56.2-68.1%], P = 0.04) and GLU and LIS (68.4% [62.7-74.1%] vs. 61.3% [55.4-67.3%], P = 0.03). No differences were seen in hemoglobin A1c at end point, most points of the seven-point glucose curves, severe hypoglycemia, and symptomatic ketoacidosis. The overall rate of hypoglycemia with a plasma glucose level below 70 mg/dL per patient-year was significantly different between GLU and ASP (73.84 vs. 65.01, P = 0.008) and GLU and LIS (73.84 vs. 62.69, P  < 0.001). Insulin doses remained unchanged during the trial. GLU was not superior to ASP and LIS with no significant difference seen among GLU, ASP, and LIS in CSII use with respect to unexplained hyperglycemia and/or perceived catheter set occlusion. GLU was associated with a higher frequency of symptomatic hypoglycemia, possibly because of slight overdosing, as previous trials suggested lower insulin requirements when GLU is initiated in type 1 diabetes