Effectiveness and safety of the MiniMed™ 780G in newly diagnosed adolescents with type 1 diabetes: an observational real-world study

Background: Evidence on starting advanced hybrid closed-loop systems (AHCL) at type 1 diabetes (T1D) onset in adolescents is limited. We evaluated the effectiveness and safety of very-early initiation of the MiniMed™ 780G advanced hybrid closed-loop system in newly diagnosed adolescents with T1D. Methods: This single-center, longitudinal, real-world observational study included adolescents aged 10–19 years who initiated MiniMed™ 780G within 30 days of T1D diagnosis (April 2023–January 2025) as standard of care. Clinical data and CareLink-derived continuous glucose monitoring (CGM) metrics were collected at pump placement (T0) and after 15 days (T1), 1 month (T2), 2 months (T3), 3 months (T4), and 6 months (T5). Outcomes included glycemic metrics (mean sensor glucose, time in range [TIR] 70–180 mg/dL, time in tight range [TITR] 70–140 mg/dL, time above range [TAR] > 180 mg/dL, time below range [TBR] < 70 mg/dL, coefficient of variation [CV], glucose management indicator [GMI]), system use (sensor wear, SmartGuard™ time), insulin delivery patterns, and safety events (severe hypoglycemia requiring glucagon, diabetic ketoacidosis [DKA]). Results: Eleven adolescents (72.7% male; mean age 11.63 ± 1.51 years) were enrolled; 72.7% presented with DKA at diagnosis. Mean glycated hemoglobin (HbA1c) at T0 was 11.71 ± 1.61% (102.18 ± 17.96 mmol/mol); HbA1c improved to 6.59 ± 0.79% at 3 months and 6.64 ± 0.46% at 6 months. Median time from diagnosis to pump start was 9 days (interquartile range [IQR] 6–20). CGM outcomes were excellent: median TIR remained high (90% at T0; 84% at T5), with very low hypoglycemia exposure (mean TBR: 2.00 ± 2.14% at T0; 1.09 ± 0.83% at T5) and mean GMI consistently < 7% (6.56 ± 0.41% at T0; 6.71 ± 0.38% at T5). Engagement was strong, with high sensor use and sustained SmartGuard™ utilization (> 98% median after T1). No severe hypoglycemia or DKA episodes occurred during 6 months of follow-up. Conclusions: Early initiation of the MiniMed™ 780G within the first month after T1D onset in adolescents was associated with rapid achievement of CGM targets, marked HbA1c improvement, and an excellent short-term safety profile, supporting early AHCL use at disease onset.