Simultaneous Measurement and Responsive Treatment - Part 2

Current insulin pump and continuous glucose monitoring systems have improved glucose management for people with type 1 diabetes but typically require multiple devices worn at different body sites. This increases treatment burden and may contribute to device-related complications, including skin irritation, site failures, and challenges with coordination between devices. Integrating insulin delivery and glucose sensing into a single system may reduce these burdens and improve usability, but placing insulin infusion and glucose sensing close together may affect CGM accuracy.

This prospective, single-arm, early feasibility study is designed to evaluate an investigational Dual Port Pump (DPP) System, which integrates an insulin infusion patch pump with a CGM sensor positioned near the insulin delivery site. The objectives of the study are to characterize the effects of insulin bolus and basal infusion on CGM sensor readings, assess glucose sensing accuracy, and collect data to support development and optimization of a sensor recovery monitoring algorithm. In Part B, the study also evaluates the feasibility and performance of an automated glycaemic control algorithm used with the integrated system.

The study is conducted in two sequential in-patient parts and enrolls adults with type 1 diabetes.

Part A (Sensor Characterization) consists of a 1.5-day in-patient admission during which participants will wear three DPP systems simultaneously. One system will deliver varying basal insulin rates, while the other two systems will deliver predefined insulin boluses. Glucose levels will be intensively monitored using reference plasma glucose measurements obtained with a Yellow Springs Instruments (YSI) glucose analyzer, along with data from a commercially available CGM. Data from the integrated CGM sensor will not be used for therapy decisions in Part A.

Part B (Automated Glycaemic Control Feasibility) consists of a 2.5-day in-patient admission during which participants will wear one DPP system. CGM values from the integrated sensor will be manually entered by trained study staff into an automated glycaemic control algorithm at regular intervals. Insulin dose recommendations generated by the algorithm will be manually applied using the pump application. Participants will consume standardized meals and complete standardized exercise sessions to evaluate glucose control under controlled conditions.

Throughout both parts of the study, glucose levels will be closely monitored, and predefined procedures are in place for the treatment of hypoglycemia and hyperglycemia. Safety data and device performance data collected in this study will be used to inform further development of an integrated insulin delivery and glucose sensing system and to support future clinical studies.

Inclusion criteria

Part A:

• Males and females ≥ 18 years of age.
• Clinical diagnosis of type 1 diabetes for at least 12 months. The diagnosis of type 1 diabetes is based on the investigator's judgment; C peptide level and antibody determinations are not needed.
• Undergoing multiple daily injection or continuous subcutaneous insulin infusion therapy for at least 3 months. Those using an automated insulin delivery system can also participate.
• Total daily insulin dose (TDD) between 30 and 100 IU.

Inclusion criteria

Part B:

• Males and females ≥ 18 years of age.
• Clinical diagnosis of type 1 diabetes for at least 12 months. The diagnosis of type 1 diabetes is based on the investigator's judgment; C peptide level and antibody determinations are not needed.
• Undergoing continuous subcutaneous insulin infusion therapy for at least 3 months. Those using an automated insulin delivery system can also participate.
• Totally daily insulin dose (TDD) between 30 and 100 IU.

Exclusion criteria

(A and B):

• Serious medical illness likely to interfere with study participation or with the ability to complete the trial by the judgment of the investigator.
• Failure to comply with the study protocol or with the team's recommendations.
• Current or recent use of any anti-hyperglycemic agent other than insulin (≤ one month for GLP1-RA, ≤ one week for all others).
• Female participants of childbearing potential who are pregnant, breastfeeding, or unwilling to use effective contraception during the study. Pregnancy will be verified by urine dipstick testing at the time of admission visit.
• Severe hypoglycemic episode within one month of admission.
• Severe diabetic ketoacidosis episode within one month of admission.
• Clinically significant nephropathy, neuropathy or retinopathy as judged by the investigator.
• Recent (<6 months) acute macrovascular event e.g., acute coronary syndrome or cardiac surgery.
• Other serious medical illness likely to interfere with study participation or with the ability to complete the trial by the judgment of the investigator.
• Current or ≤ one month use of supraphysiological doses of systemic glucocorticoids
• Pronounced lipohypertrophy in the abdominal subcutaneous adipose tissue, which may impair sensor function or insulin infusion.
• Insufficient abdominal surface area to support the wearing of three DPP systems in Part A.