Efficacy and safety of insulin degludec given as part of basal–bolus treatment with mealtime insulin aspart in type 1 diabetes: a 26-week randomized, open-label, treat-to-target non-inferiority trial

AIMS: The efficacy and safety of insulin degludec (IDeg) was compared with insulin detemir (IDet), both administered once daily (OD) as basal treatment in participants with type 1 diabetes mellitus (T1DM). The primary outcome was non-inferiority of IDeg to IDet in glycated haemoglobin (HbA1c) reduction after 26 weeks. METHODS: This multinational, 26-week, controlled, open-label, parallel-group trial randomized adults with T1DM to IDeg or IDet as OD basal insulin treatment combined with mealtime bolus insulin aspart (IAsp). Participants with T1DM treated with any basal–bolus insulin regimen for ≥12 months prior to the trial, a mean HbA1c ≤ 10.0% (85.8 mmol/mol) and body mass index (BMI) ≤35.0 kg/m(2) at screening participated in the trial (IDeg: N = 302; IDet: N = 153). RESULTS: After 26 weeks, HbA1c decreased 0.73% (8.0 mmol/mol) (IDeg) and 0.65% (7.1 mmol/mol) (IDet) [estimated treatment difference (ETD) IDeg–IDet: −0.09% (−0.23; 0.05)(95%)(CI) (−10.0 mmol/mol [−2.6; 0.6](95%) (CI)); confirming non-inferiority]. Mean fasting plasma glucose improved in both groups, and was lower with IDeg than IDet [ETD IDeg–IDet: −1.66 mmol/l (−2.37; −0.95)(95%) (CI), p < 0.0001]. The rate of confirmed hypoglycaemia was similar with IDeg and IDet [45.83 vs. 45.69 episodes per patient-year of exposure (PYE); estimated rate ratio (RR) IDeg/IDet: 0.98 (0.80; 1.20)(95%) (CI), p = 0.86]. The rate of nocturnal confirmed hypoglycaemia was lower with IDeg than IDet [4.14 vs. 5.93 episodes per PYE; RR IDeg/IDet: 0.66 (0.49; 0.88)(95%) (CI), p = 0.0049]. Adverse event profiles were similar between groups. CONCLUSION: IDeg administered OD in basal–bolus therapy effectively improved long-term glycaemic control in participants with T1DM with a lower risk of nocturnal confirmed hypoglycaemia than IDet.