Treatment intensification with an insulin degludec (IDeg)/insulin aspart (IAsp) co-formulation twice daily compared with basal IDeg and prandial IAsp in type 2 diabetes: a randomized, controlled phase III trial

Aims: To evaluate the efficacy and safety of two insulin intensification strategies for patients with type 2 diabetes previously treated with basal insulin - insulin degludec (IDeg) and insulin aspart (IAsp) - administered as a co-formulation (IDegAsp) or as a basal-bolus regimen (IDeg and IAsp in separate injections). Methods: This 26-week, open-label, treat-to-target, phase IIIb, non-inferiority trial randomized patients (1 : 1) to IDegAsp twice daily with main meals (n = 138; IDegAsp group) or IDeg once daily and IAsp 2-4 times daily (n = 136; IDeg+IAsp group). Results: After 26weeks, the mean glycated haemoglobin (HbA1c) level was 7.0% (53 mmol/mol) for the IDegAsp group and 6.8% (51 mmol/mol) for the IDeg+IAsp group (Delta% HbA1c from baseline-1.31 and -1.50%, respectively). The non-inferiority of IDegAsp versus IDeg+IAsp was not confirmed for mean change in HbA1c [ estimated treatment difference (ETD) 0.18, 95% confidence interval (CI)-0.04, 0.41; p = non-significant]. No significant differences were observed in the proportion of patients achieving HbA1c < 7.0% (56.5 and 59.6%, respectively). IDegAsp treatment resulted in a significantly lower total daily insulin dose, a smaller change in body weight, numerically lower rates of confirmed hypoglycaemia (self-reported plasma glucose <3.1 mmol/l; rate ratio 0.81; p = non-significant), and nocturnal confirmed hypoglycaemic episodes (rate ratio 0.80; p = non-significant) versus IDeg+ IAsp. Patient-reported outcome scores for social functioning were significantly higher for IDegAsp versus IDeg+IAsp (ETD 2.2; 95% CI 0.3, 4.1; p < 0.05). Conclusions: Both intensification strategies effectively improved glycaemic control. Although non-inferiority was not confirmed, there were no significant differences between the groups that could affect clinical utility.