Safety and efficacy of insulin degludec/insulin aspart with bolus mealtime insulin aspart compared with standard basal–bolus treatment in people with Type 1 diabetes: 1–year results from a randomized clinical trial (<scp>BOOST</scp>^®T1)

Abstract

Abstract Aims To evaluate the long‐term safety and efficacy of a simplified basal–bolus regimen of once‐daily insulin degludec/insulin aspart ( ID egAsp) with additional IA sp vs. a standard basal–bolus insulin regimen of insulin detemir ( ID et) with IA sp in adults with Type 1 diabetes. Methods This was an open‐label trial comprising a 26‐week core phase followed by a 26‐week extension phase. Participants were randomized to ID egAsp once daily at the main meal and IA sp at remaining meals ( ID egAsp+ IA sp), or ID et (once or twice daily) and IA sp at all meals ( ID et+ IA sp). Insulins were titrated to target plasma glucose of &lt; 5 mmol/l (&lt; 90 mg/dl) at pre‐breakfast ( ID egAsp and ID et) and at pre‐meal ( IA sp). Results After 52 weeks, the overall confirmed hypoglycaemia rate was 31.8 episodes/patient‐years of exposure ( PYE ) with ID egAsp+Asp and 36.7 episodes/ PYE with ID et+ IA sp, and the rate of nocturnal confirmed hypoglycaemia was significantly lower with ID egAsp+Asp than with ID et+ IA sp (3.1 vs. 5.4 episodes/ PYE , respectively; P &lt; 0.05). Adverse event rates were comparable between groups. Mean HbA 1c decreased from baseline by 0.7% ( ID egAsp+ IA sp) and 0.6% ( ID et+ IA sp), achieving 60 or 61 mmol/mol (7.6% or 7.7%, respectively), at Week 52. The mean total daily insulin dose was lower with ID egAsp+ IA sp than with ID et+ IA sp (ratio: 0.87; 95% CI 0.79–0.95; P = 0.0026). Conclusions Once‐daily treatment with ID egAsp and IA sp as bolus insulin for remaining meals was associated with significantly lower risk of nocturnal confirmed hypoglycaemia, improved glycaemic control and showed non‐inferiority compared with ID et+ IA sp, the standard of care in Type 1 diabetes.