Improved Glycemia with Hybrid Closed-Loop (HCL) Versus Continuous Subcutaneous Insulin Infusion (CSII) Therapy: Results from a Randomized Controlled Trial.

OBJECTIVE
To evaluate safety and effectiveness of MiniMed™ 670G hybrid closed loop in comparison with continuous subcutaneous insulin infusion (CSII) therapy for six months, in persons with type 1 diabetes (T1D).


METHODS
Adults (aged 18-80 years), adolescents, and children (aged 2-17 years) with T1D who were using CSII therapy were enrolled and randomized (1:1) to six months of HCL intervention (N=151, mean age of 39.9±19.8 years) or CSII control (N=151, 35.7±18.4 years) without continuous glucose monitoring. Primary effectiveness endpoints included change in A1C for Group 1 (baseline A1C >8.0%), from baseline to the end of study, and difference in the end of study percentage of time spent below 70 mg/dL (%TBR<70 mg/dL) for Group 2 (baseline A1C ≤8.0%), to show superiority of HCL intervention versus control. Secondary effectiveness endpoints were change in A1C and %TBR<70 mg/dL for Group 2 and Group 1, respectively, to show non-inferiority of HCL intervention versus control. Primary safety endpoints were rates of severe hypoglycemia and diabetic ketoacidosis (DKA).


RESULTS
Change in A1C and difference in %TBR<70 mg/dL for the overall group were significantly improved, in favor of HCL intervention. In addition, a significant mean (95% CI) change in A1C was observed for both Group 1 (-0.8% [-1.1%,-0.4%], p<0.0001) and Group 2 (-0.3% [-0.5%,-0.1%], p<0.0001), in favor of HCL intervention. The same was observed for difference in %TBR<70 mg/dL for Group 1 (-2.2% [-3.6%,-0.9%]) and Group 2 (-4.9% [-6.3%,-3.6%]) (p<0.0001 for both). There was one DKA event during run-in and six severe hypoglycemic events: two during run-in and four during study (HCL: N=0 and CSII: N=4 [6.08 per 100 patient-years]).


CONCLUSIONS
This RCT demonstrate that the MiniMed 670G system safely and significantly improved A1C and %TBR<70 mg/dL with HCL intervention compared with CSII control in persons with T1D, irrespective of baseline A1C level.