Automated insulin delivery maintains effective glycemic control in young children with type 1 diabetes (T1D). The LENNY trial extension phase evaluated children aged 2–6 years using a closed-loop insulin delivery system with either the standard glucose sensor or a new all-in-one sensor. The study was presented at the European Association for the Study of Diabetes (EASD) 2025.

Ninety-one children who completed the initial trial phase continued in the extension: 46 continued with the standard sensor and 45 switched to the new sensor. After 12 weeks, mean HbA1c was 7.24% and 7.30%, respectively, confirming non-inferiority between sensors. Time in Range remained stable at 68.9% and 69.7%, and Time Below Range remained low. No severe hypoglycemia or diabetic ketoacidosis occurred during the 12-week period. Glycemic improvements achieved in the initial 18-week phase were sustained, and the new sensor performed comparably to the standard sensor.

The extension phase confirms that automated insulin delivery maintains stable glucose control and low hypoglycemia risk in young children with T1D over seven months. These findings support its long-term safety and effectiveness.