Closed-loop insulin therapy for people with type 2 diabetes treated with an insulin pump: a 12-week multicenter, open-label randomized controlled crossover trial

Objective: Continuous glucose monitoring (CGM) combined with continuous subcutaneous insulin infusion (CSII) achieves better glycemic control than multi-injection therapy in people with type 2 diabetes. The effectiveness of closed-loop therapy needs to be further evaluated in this population.

Research Design and Methods: The study objective was to measure the impact of a hybrid closed-loop device (DBLG1) compared to CSII+CGM on glycemic control in people with type 2 diabetes previously treated with CSII. The study was randomized, controlled, cross-over, two-period, open-label, and multicenter conducted from August 2022 to July 2023 in 17 individuals (9 to receive six weeks of CSII+CGM first and 8 to receive six weeks of closed-loop therapy first). The primary endpoint was the percentage time in range (TIR: [70-180] mg/dL). Secondary outcomes were other CGM-glucose metrics, physical activity, and sleep objectively measured using one-week actimetry.

Results: Data were analyzed using a modified intention-to-treat approach. Mean (SD) age was 63 (9) years and 35% were female. Mean HbA1c at inclusion was 7.9 (0.9)%. TIR increased to 76.0 (IQR: 69.0; 84.0)% during the closed-loop condition vs. 61.0 (55.0-70.0)% during the CSII+CGM condition; mean difference 15.0 (95%CI: 8.0; 22.0) percentage points, p<0.001. Analyses of secondary endpoints showed a decrease in time above range, in glucose management indicator, in glucose variability and an increase in daily insulin dose. Actimetric sleep analysis showed an improvement in sleep fragmentation during closed-loop treatment.

Conclusion: Closed-loop therapy improved glycemic control above than did CSII+CGM in people with type 2 diabetes.