215-OR: Performance of a Dual Hormone Closed-Loop System vs. an Insulin-Only Closed-Loop System during Challenging Inpatient Conditions: A Single-Blinded Randomized Controlled Crossover Trial

Objective: To assess the efficacy and safety of an insulin-glucagon dual-hormone (DH) compared with an insulin-only single-hormone (SH) closed-loop system. Methods: In a 33-h, randomized, crossover, inpatient study, 13 participants with type 1 diabetes used two modes of the DiaCon Artificial Pancreas system: DH and SH closed-loop control. During each study period, participants had two overnight stays, received an underbolus (50%) for their breakfast, normal bolus (100%) for lunch, overbolus (130%) for dinner and performed unannounced exercise for 45 min (bicycled at estimated 50% V02max). The co-primary endpoints were sensor-based percentage of time in hypoglycemia ( Results: Overall, the average number of carbohydrate rescues was significantly lower during DH compared with SH (mean±SD: 0.8±1.3 vs. 1.4±1.4 per 33 h, p = 0.04). The percentages of time in hypoglycemia (3.6±2.1% vs. 3.8±3.3%, p = 0.46), target range (3.9-10.0 mmol/L: 67.2±15.4% vs. 65.3±12.4%, p = 0.41) and hyperglycemia (>10.0 mmol/L: 26.8±16.0% vs. 28.7±12.7%, p = 0.41) were similar between study arms. Mean glucose was lower for DH than SH (8.3±1.2 vs. 8.6±1.0 mmol/L, p = 0.04) with similar coefficient of variation (40±8.3 vs. 38±5.0%, p = 0.30). From exercise start and 4 h onwards, DH achieved more time in range (86.7±11.7 vs. 74.7±16.5%, p = 0.01), but similar time in hypoglycemia (10.5±18.7 vs. 12.6±24.3%, p = 0.32) and numbers of carbohydrate rescues (5±0.7 vs. 6±0. 7, p = 0.38). No differences were observed on visual analog scale-measured nausea (p = 0.47), headache (p = 0.77), hunger (p = 0.66), and palpitation (p = 0.11). Conclusions: During challenging inpatient conditions, the DH system achieved similar glucose control but significantly reduced need for carbohydrate rescue compared with SH. Disclosure A. G. Ranjan: None. D. Boiroux: Consultant; Self; Novo Nordisk A/S, Employee; Spouse/Partner; Novo Nordisk A/S. C. Laugesen: None. S. Schmidt: None. A. T. Reenberg: None. J. B. Jorgensen: None. K. Norgaard: Advisory Panel; Self; Medtronic, Other Relationship; Self; Novo Nordisk Inc., Zealand Pharma A/S, Speaker’s Bureau; Self; Medtronic. Funding Danish Diabetes Association; Danish Diabetes Academy (PD002-19)