Hybrid Closed-Loop with Faster Insulin Aspart Compared with Standard Insulin Aspart in Very Young Children with Type 1 Diabetes: A Double-Blind, Multicenter, Randomized, Crossover Study

We evaluated the use of hybrid closed-loop (HCL) insulin delivery with faster insulin aspart (Fiasp) in very young children with type 1 diabetes (T1D). In a double-blind, multicenter, randomized, crossover study, children aged 2-6 years with T1D underwent two 8-week periods of HCL using CamAPS FX with Fiasp and standard insulin aspart (IAsp), in random order. Primary endpoint was between-treatment difference in time in target range 3.9-10.0 mmol/L. We randomized 25 participants: mean (±standard deviation) age 5.1 ± 1.3 years, baseline HbA1c 55 ± 9 mmol/mol. Time in range was not significantly different between interventions (64% ± 9% vs. 65% ± 9% for HCL with Fiasp vs. IAsp; mean difference -0.33% [95% confidence interval: -2.13 to 1.47; P = 0.71]). There was no significant difference in time with glucose