The following is the summary of “Improved Glycemia with Hybrid Closed-Loop Versus Continuous Subcutaneous Insulin Infusion Therapy: Results from a Randomized Controlled Trial” published in the December 2022 issue of Diabetes technology and therapeutics by Garg, et al.

The purpose of this study is to compare the safety and efficacy of 6 months of continuous subcutaneous insulin infusion (CSII) therapy with MiniMedTM 670G HCL use in people with type 1 diabetes (T1D). Participants included adults (aged 18-80 years), adolescents (aged 12-17 years), and children (aged 2-17 years) with type 1 diabetes who were receiving CSII therapy and were randomly assigned (1:1) to either 6 months of HCL intervention (n=151, mean age 39.9 19.8 years) or CSII without continuous glucose monitoring (n=151, mean age 35.7  ± 18.4 years). Primary effectiveness endpoints for demonstrating the superiority of the HCL intervention over the control group were the percentage of time spent with a blood sugar level below 70 mg/dL (%TBR 70 mg/dL) at the end of the study for Group 2 (baseline A1C≤8.0%) and the change in A1C from baseline to the end of the study for Group 1 (baseline A1C >8.0%). 

Noninferiority of the HCL intervention compared to the control group was demonstrated by achieving a change in A1C and %TBR 70 mg/dL in Group 2 and Group 1, respectively. Rates of severe hypoglycemia and diabetic ketoacidosis(DKA) were the primary safety goals. For the entire group, the results showed a significant improvement in terms of change in A1C and difference in %TBR <70 mg/dL, both of which favored the HCL intervention. The average (95% CI) decrease in A1C was also significantly lower after HCL intervention in Group 1 -(-0.8% [1.1% to 0.4%], P<0.0001) and Group 2 (0.3% [-0.5% to -0.1%], P<0.0001). Similar results were seen when comparing the percentage of people in Group 1 with a TBR <70 mg/dL to those in Group 2 (-2.2% [-3.6% to -0.9%] vs. 4.9% [-6.3% to -3.6%]; P<0.0001 for both). 

There was one case of diabetic ketoacidosis (DKA) during the run-in and 6 cases of severe hypoglycemia (HCL: n=0 and CSII: n=4 [-6.08 per 100 patient-years]), 2 of which occurred during the run-in. All participants with T1D, regardless of their baseline A1C level, benefited from the MiniMed 670G HCL’s safe and significant improvement in A1C and %TBR <70 mg/dL compared with CSII control, as shown by this randomized controlled trial.