Safety and Feasibility of a Self-Learning Bolus Calculator With Simplified Meal Announcement in Adolescents With Type 1 Diabetes Using Automated Insulin Delivery

Following recruitment and screening, participants will be randomized to one of two sequences during the Hotel Admission: AID+InsuLearn-SMA→AID+CC or AID+CC→AID+InsuLearn-SMA. All participants will be trained on the study equipment, which includes (i) the DiAs smartphone running the Control-IQ algorithm with either the InsuLearn-SMA bolus calculator or the standard carbohydrate counting bolus calculator, and (ii) the Dexcom CGM. All participants will complete 7 days/6 nights run-in At-Home Period using the AID+CC system (Control-IQ with the standard carbohydrate counting bolus calculator). Participants will then undergo a 2-night supervised hotel admission (approximately 48 hours). During this admission, each participant will consume two standardized meals (dinner and breakfast), during which either the InsuLearn-SMA bolus calculator or the standard CC bolus calculator will be used in a randomized order. Two lunches will be offered during the Hotel Admission but not included in the analysis. Following discharge, all participants will complete 7 days/6 nights At-Home Period using the AID+InsuLearn-SMA system before returning the study equipment. The INSPIRE Questionnaire will be administered before and after the Hotel Admission. Additionally, participants will be asked to provide a 2-week CGM data download of their usual care for statistical analysis before randomization and after returning the equipment.

Inclusion criteria

• Age ≥14.0 and ≤21 years old at time of consent
• HbA1c ≤ 10%.
• Clinical diagnosis, based on investigator assessment, of type 1 diabetes for at least one year
• Having used an insulin pump within the last three months.
• Currently using insulin for at least six months
• Willingness to use insulin parameters such as carbohydrate ratio and correction factors consistently on their pump in order to dose insulin for meals or corrections
• Willingness to switch to a commercially approved insulin (e.g. lispro or aspart or biosimilar approved products) within the study pump as directed by the study team.
• Has one or more supportive caregivers or companions living with the participant who are knowledgeable about emergency procedures for treatment of severe hypoglycemia and able to contact emergency services and study staff.
• Acceptable forms of contraception for participants of child-bearing potential include hormonal treatments including IUD, abstinence from heterosexual intercourse, vasectomy in partner, barrier methods (e.g. condom or diaphragm).
• For females, not currently known to be pregnant or breastfeeding. A negative serum or urine pregnancy test will be required for all females of childbearing potential. Participants who become pregnant will be discontinued from the study. Also, participants who during the study develop and express the intention to become pregnant within the timespan of the study will be discontinued.
• Willingness to use the study InsuLearn system (CGM, pump, and phone) during the study period.
• Willingness not to start any new non-insulin glucose-lowering agent during the course of the trial.
• Access to internet at home and ability to upload data during the study as needed.
• Investigator has confidence that the participant can successfully operate all study devices and is capable of adhering to the protocol.
• Participant is proficient in reading and writing English.

Exclusion criteria

• History of diabetic ketoacidosis (DKA) in the 12 months prior to enrollment
• Severe hypoglycemia resulting in seizure or loss of consciousness in the 12 months prior to enrollment
• Pregnancy or intent to become pregnant during the trial
• Currently breastfeeding or planning to breastfeed
• Currently being treated for a seizure disorder
• Planned surgery during study duration
• History of cardiac arrhythmia (except for benign premature atrial contractions and benign premature ventricular contractions which are permitted)
• Treatment with any non-insulin glucose-lowering agent (including metformin, GLP-1 agonists, pramlintide, DPP-4 inhibitors, SGLT-2 inhibitors, biguanides, sulfonylureas and naturaceuticals)
• A known medical condition that in the judgment of the investigator might interfere with the completion of the protocol.
• Participation in another interventional trial at the time of enrollment.
• Visual impairment/blindness that prevents proper interaction with study equipment
• Participant who may have a falsely eligible HbA1c due to medical conditions or blood donations.
• Participants in whom the G6 CGM may be inaccurate due to interference.