Aims: The efficacy of two basal insulins, insulin lispro protamine suspension (ILPS) and insulin detemir, was compared in basal-bolus regimens in Type 1 diabetes.
Methods: In this 32-week, multinational, parallel-group, randomized, controlled trial, adult patients with Type 1 diabetes received ILPS or insulin detemir, injected twice daily (before breakfast and bedtime) and prandial insulin lispro three times daily. The primary outcome was change in glycated haemoglobin (HbA(1c)) from baseline to endpoint.
Results: Least squares mean (+/-se) changes in HbA(1c) were similar between groups, meeting non-inferiority (margin, 0.4%): -0.69 +/- 0.07% for ILPS and -0.59 +/- 0.07% for insulin detemir [between-treatment difference -0.10%; 95% confidence interval (CI) -0.29, 0.10]. Standard deviation of fasting blood glucose was similar (non-inferiority margin 0.8 mmol/l): 2.74 +/- 0.14 mmol/l for ILPS and 2.38 +/- 0.14 mmol/l for insulin detemir (CI -0.03, 0.75). Patients on ILPS gained more weight (1.59 +/- 0.23 kg vs. 0.62 +/- 0.24 kg; CI 0.34, 1.60; margin 1.5 kg). Weight-adjusted daily total and prandial insulin doses were lower for ILPS (prandial insulin, 0.38 +/- 0.01 U/kg/day for ILPS, 0.44 +/- 0.01 U/kg/day for insulin detemir; P = 0.004); daily basal insulin dose was similar. All hypoglycaemia incidence and rate and nocturnal hypoglycaemia incidence were similar between groups; nocturnal hypoglycaemia rate was lower for insulin detemir (mean +/- sd 0.79 +/- 1.23 for ILPS, 0.49 +/- 0.85 for insulin detemir; P = 0.001). Severe hypoglycaemia rate was 0.03 +/- 0.11 for ILPS and 0.02 +/- 0.10 for insulin detemir (P = 0.37).
Conclusions: ILPS-treated patients with Type 1 diabetes achieved similar glycaemic control as insulin detemir-treated patients after 32 weeks. Glucose variability was similar. While weight gain and nocturnal hypoglycaemia rate were statistically higher with ILPS, the clinical relevance is unclear.