The Insulin-Only Bionic Pancreas Pivotal Trial Extension Study: A Multi-Center Single-Arm Evaluation of the Insulin-Only Configuration of the Bionic Pancreas in Adults and Youth with Type 1 Diabetes

Objective: To evaluate a transition from standard-of-care (SC) management of type 1 diabetes (any insulin delivery method including hybrid closed-loop systems plus real-time continuous glucose monitoring [CGM]) to use of the insulin-only configuration of the iLet((R)) bionic pancreas (BP) in 90 adults and children (age 6-71 years). Research Design and Methods: After the SC group completed the randomized controlled trial (RCT) portion of the Insulin-Only BP Pivotal Trial, 90 of the 107 participants participated in a 13-week study using the BP. The key outcomes were change from baseline in HbA1c and CGM metrics after 13 weeks on the BP. Results: Using the BP, mean HbA1c decreased from 7.7%1.0% (6110.9mmol/mol) at baseline to 7.1%+/- 0.6% (54 +/- 6.6mmol/mol) at 13 weeks (mean change -0.55%+/- 0.72% [-6 +/- 7.9mmol/mol], P<0.001), time in range 70-180mg/dL increased by 12.0%+/- 12.5% (from 53%+/- 17% to 65%+/- 9%, P<0.001), and mean glucose decreased by -18 +/- 23mg/dL (from 182 +/- 32 to 164 +/- 15mg/dL, P<0.001). The higher the baseline HbA1c level, the greater the change in HbA1c. Results were similar in the adult (N=42) and pediatric (N=48) cohorts. Time <70mg/dL decreased from baseline over the 13 weeks by -0.50%+/- 1.86% (P=0.02), and time <54mg/dL was similar (change from baseline -0.08%+/- 0.59%, P=0.24). Two severe hypoglycemia events (in same participant) and one diabetic ketoacidosis event occurred. Conclusions: Glycemic control improved after adult and pediatric participants in the SC arm in the Insulin-Only BP Pivotal Trial transitioned to use of the BP. Improvement using the BP was of similar magnitude to that observed during the RCT.

Automated summary

This study evaluated the effectiveness of transitioning from standard-of-care management to insulin-only configuration of the iLet bionic pancreas in patients with type 1 diabetes. The results showed that glycemic control improved, with a decrease in HbA1c levels and an increase in time spent within the target range.