Efficacy and safety of switching from basal insulin to once-daily insulin degludec/insulin aspart in Japanese patients with inadequately controlled type 2 diabetes: A 4-week, randomized, open-label, treat-to-target study

Aims/introduction: A prospective, 4-week, single-center, randomized, open-label, parallel-group, treat-to-target study was carried out to develop an algorithm for safe and effective switching from basal insulin to once-daily insulin degludec/insulin aspart (IDegAsp) in patients with inadequately controlled type 2 diabetes.

Materials and methods: Patients were randomly assigned to continue their current basal insulin therapy (n = 10) or to switch to IDegAsp on a 1:1 unit basis (n = 10). The insulin dose could be titrated once weekly, targeting a self-measured blood glucose of 80-100 mg/dL before breakfast. A mixed meal test was carried out at baseline and after 4 weeks.

Results: After 4 weeks, the mean daily dose of insulin was similarly increased by 60% in both groups, and there was a significant decrease of mean plasma glucose and glucose area under the glucose concentration vs time curve for 2 h in the meal test. The mean estimated treatment difference (IDegAsp group - basal insulin group) of the mean plasma glucose level was -28 mg/dL (95% confidence interval -47 to -8, P = 0.008) after 4 weeks and that of the area under the glucose concentration vs time curve for 2 h was -2,800 mg/min/dL (95% confidence interval -5,300 to -350, P = 0.028), confirming the superiority of IDegAsp to basal insulin. In the IDegAsp group, the 2-h postprandial plasma glucose level was significantly decreased to the fasting plasma glucose range. There were no confirmed hypoglycemic episodes in either group during the 4-week study period.

Conclusions: After switching from basal insulin, the IDegAsp dose can be uptitrated by 60% based on fasting plasma glucose data. However, monitoring of postprandial glucose should be considered before further uptitration of IDegAsp.