Improved glycaemic control with carbohydrate counting for adjustment of fast-acting insulin aspart

Aims: insulin delivery based on carbohydrate counting is the gold standard for improving glycaemic control in Type 1 diabetes. The aim of this analysis was to assess the impact of dose-adjustment methodology on the efficacy and safety of mealtime fast-acting insulin aspart (faster aspart) and insulin aspart (IAsp) in subjects with Type 1 diabetes. Methods: post hoc analysis of onset 1, a 26-week, phase 3 trial in which subjects were randomised to double-blind faster aspart or IAsp, both with insulin detemir. Subjects with previous experience continued carbohydrate counting (baseline HbA1c, faster aspart and IAsp 7.6%) and remaining subjects used a simple bolus algorithm (baseline HbA1c, faster aspart 7.5%, IAsp 7.6%). In the post hoc analysis, subjects were grouped by dose-adjustment method. Results: faster aspart showed a statistically significant greater reduction in HbA1c versus IAsp, and non-inferiority was confirmed (estimated treatment difference [ETD]: -0.15% [95% CI: -0.23;-0.07]). With carbohydrate counting, HbA1c reduction was significantly greater for faster aspart versus IAsp (ETD: -0.19% [-0.30;-0.09]), but was similar for both treatments with the bolus algorithm (ETD: -0.08 [-0.21;0.04]). Hypoglycaemia rates and bolus dose were similar between treatments across adjustment methods. No significant differences in total dose or weight gain were observed between treatments with either adjustment method. Conclusion: faster aspart was effective in glycaemic control regardless of adjustment method. For patients with Type 1 diabetes capable of dosing based on carbohydrate counting, faster aspart may offer improved glycaemic control versus IAsp, with similar weight gain and insulin dose, without increased risk of hypoglycaemia.