Hybrid Closed-Loop Control with Ultrarapid Lispro Compared with Standard Insulin Aspart and Faster Insulin Aspart: An In Silico Study.

OBJECTIVE: There is room for improvement in the performance of closed-loop regulation algorithms during the prandial period. This in silico study evaluated the efficiency and safety of ultrarapid lispro insulin using the Diabeloop DBLG1® algorithm. METHODS: We modeled the insulin profile of URLi according to literature data and integrated it to the model used within a simulation platform built from a 60 patients' virtual cohort. We then ran the DBLG1® algorithm in silico with various meal intakes using modeled URLi, Aspart and Faster Aspart. The primary endpoints were glucose metrics (time in 70-180 mg/dL range and time below range). RESULTS: When insulin time constant values were tuned, time in 70-180 mg/dL range was 69.4 [61.1-75.6] (Aspart) vs 74.7 [65.5-81.5] (URLi). Glucose coefficient of variation was reduced from 34.1 [29.7-37.8] to 28.4 [25.7-34.6]. Time below 70 mg/dL and 54 mg/dL were significantly reduced with URLi, whether or not DBLG1 was specifically tuned to this insulin. Metrics with Faster Aspart were intermediate and did not significantly differ from URLi. CONCLUSIONS: This simulation study performed on a virtual T1D population suggests that the use of URLi within an unmodified closed-loop DBLG1 regulation algorithm is safe and, with DBLG1 being tuned to this specific insulin type, improved the regulation performances as compared with Aspart. This fact supports the use of such an insulin in clinical investigations.

Hybrid closed-loop insulin delivery versus sensor-augmented pump therapy in children aged 6-12 years: a randomised, controlled, cross-over, non-inferiority trial.

BACKGROUND: Time in range (TIR) goals are rarely met in children with type 1 diabetes, except at the cost of increased hypoglycaemia episodes. Our objective was to evaluate the safety and efficiency of the Diabeloop DBL4K (Diabeloop, Grenoble, France) hybrid closed-loop system in prepubescent children. METHODS: We did a multicentre, open-label, randomised, controlled, non-inferiority, two-session crossover study in the paediatric endocrinology departments of three university hospitals in France and Belgium. Eligible participants were aged 6-12 years with type 1 diabetes for at least 1 year, glycated haemoglobin A1C 9% (75 mmol/mol) or less, and insulin pump treatment for at least 3 months. Participants were randomly assigned (1:1) to a closed-loop device or sensor-augmented pump (open loop) therapy. Randomisation was by a permuted block randomisation scheme, using an interactive web-based response system, and was stratified on centre (block size 6). The assessed closed-loop device, the Diabeloop for Kids DBL4K hybrid closed-loop system, is an automated blood glucose regulation system composed of a handset, insulin pump, and continuous glucose monitor. The open-loop system is defined as a sensor-augmented pump therapy composed of the usual insulin pump used by the patient and a continuous glucose monitor. A 72-h in-patient period was followed by a 6-week home phase. After a 1-week washout period, the participants crossed over to the other device. The primary outcome, assessed in the intention-to-treat population, was the mean proportion of time spent in hypoglycaemia (3·9 mmol/L [<70 mg/dL]) during the hospital phase, with a non-inferiority margin of -2·5% (absolute value). Safety was assessed in the intention-to-treat population on a per-protocol basis. This study was registered with ClinicalTrials.gov, NCT03671915. FINDINGS: Between May 6 and Dec 23, 2019, we included 21 participants (closed loop then open loop, n=10; open loop then closed loop, n=11). The proportion of time spent in hypoglycaemia was significantly lower with the closed-loop system than the open-loop system in both groups (2·04% [95% CI 0·44 to 3·64] vs 7·06% [5·46 to 8·66]; non-inferiority one-sided p<0·0001). No severe ketoacidosis, nor severe hyoglycaemic events or fatal adverse events occurred. All 25 adverse events (18 with the closed-loop system, seven with the open-loop system) were related to the treatment. INTERPRETATION: The closed-loop Diabeloop system decreased hypoglycaemic episodes and provided good metabolic control in prepubescent children with type 1 diabetes, under real-life conditions. This finding supports the safe use of closed-loop technology in this paediatric population. FUNDING: Diabeloop. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.

Short course corticosteroid treatment and closed-loop insulin delivery system: The experience of the DBLG1 pre-launch.

No abstract (brief report).

No more hypoglycaemia on days with physical activity and unrestricted diet when using a closed-loop system for 12 weeks: A post hoc secondary analysis of the multicentre, randomized controlled Diabeloop WP7 trial.

A post hoc analysis of the Diabeloop WP7 multicentre, randomized controlled trial was performed to investigate the efficacy of the Diabeloop Generation-1 (DBLG1) closed-loop system in controlling the hypoglycaemia induced by physical activity (PA) in real-life conditions. Glycaemic outcomes were compared between days with and without PA in 56 patients with type 1 diabetes (T1D) using DBLG1 for 12 weeks. After the patient announces a PA, DBLG1 reduces insulin delivery and, if necessary, calculates the amount of preventive carbohydrates (CHO). Daily time spent in the interstitial glucose range less than 70 mg/dL was not significantly different between days with and without PA (2.0% ± 1.5% vs. 2.2% ± 1.1%), regardless of the intensity or duration of the PA. Preventive CHO intake recommended by the system was significantly higher in days with PA (41.1 ± 35.5 vs. 21.8 ± 28.5 g/day; P < .0001), and insulin delivery was significantly lower (31.5 ± 10.5 vs. 34.0 ± 10.5 U/day; P < .0001). The time spent in hyperglycaemia and the glycaemic variation coefficient increased significantly on days with PA. In real-life conditions, the use of DBLG1 avoids PA-induced hypoglycaemia. Insulin adjustments and preventive CHO recommendation may explain this therapeutic benefit.

Diabeloop DBLG1 Closed-Loop System Enables Patients With Type 1 Diabetes to Significantly Improve Their Glycemic Control in Real-Life Situations Without Serious Adverse Events: 6-Month Follow-up.

OBJECTIVE: To analyze safety and efficacy of the Diabeloop Generation 1 (DBLG1) hybrid closed-loop artificial pancreas system in patients with type 1 diabetes in real-world conditions. RESEARCH DESIGN AND METHODS: After a 1-week run-in period with their usual pump, 25 patients were provided the commercial DBLG1 system. The results are presented on time in range (TIR) and HbA1c over 6 months. RESULTS: The mean (SD; range) age of patients was 43 (13.8; 25-72) years. At baseline, the mean HbA1c and TIR 70-180 mg/dL were, respectively, 7.9% (0.93; 5.6-8.5%) [63 mmol/mol (10; 38-69 mmol/mol)] and 53% (16.4; 21-85%). One patient stopped using the system after 2 months. At 6 months, the mean HbA1c decreased to 7.1% [54 mmol/mol] (P < 0.001) and TIR 70-180 mg/dL increased to 69.7% (P < 0.0001). TIR <70 mg/dL decreased from 2.4 to 1.3% (P = 0.03), and TIR <54 mg/dL decreased from 0.32 to 0.24% (P = 0.42). No serious adverse event was reported during the study. CONCLUSIONS: The ability of the DBLG1 system to significantly improve glycemic control in real-world conditions, without serious adverse events, was confirmed in this follow-up study.

Increasing the safety of unannounced meal detection for artificial pancreas closed-loop with patient's hourly meal schedule.

The daily challenge for people with type 1 diabetes is maintaining glycaemia in the "normal" range after meals, by injecting themselves the correct amount of insulin. Artificial pancreas systems were developed to adjust insulin delivery based on real-time monitoring of glycaemia and meal patient's report. Meal reporting is a heavy burden for patients as it requires carbohydrate estimation several times per day. To improve patient's quality of life and treatment, several methods aim at detecting unannounced meals. While untreated meals lead to hyperglycaemia and in the long-term to comorbidities, treating falsely detected meals can cause hypoglycaemia and coma. In this paper, we propose to customise the meal detection to the patient's hourly meal probability in order to limit false detection of unannounced meals.

Efficacy of the Diabeloop closed-loop system to improve glycaemic control in patients with type 1 diabetes exposed to gastronomic dinners or to sustained physical exercise.

AIMS: To compare closed-loop (CL) and open-loop (OL) systems for glycaemic control in patients with type 1 diabetes (T1D) exposed to real-life challenging situations (gastronomic dinners or sustained physical exercise). METHODS: Thirty-eight adult patients with T1D were included in a three-armed randomized pilot trial (Diabeloop WP6.2 trial) comparing glucose control using a CL system with use of an OL device during two crossover 72-hour periods in one of the three following situations: large (gastronomic) dinners; sustained and repeated bouts of physical exercise (with uncontrolled food intake); or control (rest conditions). Outcomes included time in spent in the glucose ranges of 4.4-7.8 mmol/L and 3.9-10.0 mmol/L, and time in hypo- and hyperglycaemia. RESULTS: Time spent overnight in the tight range of 4.4 to 7.8 mmol/L was longer with CL (mean values: 63.2% vs 40.9% with OL; P ≤ .0001). Time spent during the day in the range of 3.9 to 10.0 mmol/L was also longer with CL (79.4% vs 64.1% with OL; P ≤ .0001). Participants using the CL system spent less time during the day with hyperglycaemic excursions (glucose >10.0 mmol/L) compared to those using an OL system (17.9% vs 31.9%; P ≤ .0001), and the proportions of time spent during the day with hyperglycaemic excursions of those using the CL system in the gastronomic dinner and physical exercise subgroups were of similar magnitude to those in the control subgroup (18.1 ± 6.3%, 17.2 ± 8.1% and 18.4 ± 12.5%, respectively). Finally, times spent in hypoglycaemia were short and not significantly different among the groups. CONCLUSIONS: The Diabeloop CL system is superior to OL devices in reducing hyperglycaemic excursions in patients with T1D exposed to gastronomic dinners, or exposed to physical exercise followed by uncontrolled food and carbohydrate intake.

Customization of home closed-loop insulin delivery in adult patients with type 1 diabetes, assisted with structured remote monitoring: the pilot WP7 Diabeloop study.

AIMS: Improvement in closed-loop insulin delivery systems could result from customization of settings to individual needs and remote monitoring. This pilot home study evaluated the efficacy and relevance of this approach. METHODS: A bicentric clinical trial was conducted for 3 weeks, using an MPC-based algorithm (Diabeloop Artificial Pancreas system) featuring five settings designed to modulate the reactivity of regulation. Remote monitoring was ensured by expert nurses with a web platform generating automatic Secured Information Messages (SIMs) and with a structured procedure. Endpoints were glucose metrics and description of impact of monitoring on regulation parameters. RESULTS: Eight patients with type 1 diabetes (six men, age 41.8 ± 11.4 years, HbA1c 7.7 ± 1.0%) were included. Time spent in the 70-180 mg/dl range was 70.2% [67.5; 76.9]. Time in hypoglycemia < 70 mg/dl was 2.9% [2.1; 3.4]. Eleven SIMs led to phone intervention. Original default settings were modified in all patients by the intervention of the nurses. CONCLUSION: This pilot trial suggests that the Diabeloop closed-loop system could be efficient regarding metabolic outcomes, whereas its telemedical monitoring feature could contribute to enhanced efficacy and safety. This study is registered at ClinicalTrials.gov with trial registration number NCT02987556.