NCT05083559

Two Way Crossover Closed Loop Study R-AP vs MPC

A Crossover Study to Assess the Efficacy of a Robust AP Closed Loop System vs MPC Closed Loop System

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 15 (actual)
• Sponsor: Oregon Health and Science University · Academic / Other
• Sex: All
• Age: 18 Years – 65 Years
• Healthy volunteers: Not accepted

Summary

An artificial pancreas (AP) is a control system for automatic insulin delivery. The investigators have implemented a missed meal bolus detection algorithm for use within an AP control system. The robust R-AP system used in this protocol has been designed to handle a variety of real-world scenarios that are critical to a high-risk patient population. The investigators will test how well the new algorithm handles missed or inaccurate meal announcements. This type of algorithm may significantly improve glucose control over the standard model predictive control (MPC) closed-loop algorithm without these new algorithm features for patients with type 1 diabetes.

Detailed description

Participants will undergo two visits at Oregon Health and Science University (OHSU) that will evaluate missed meal bolus detection. Participants will arrive at approximately 7am for all visits, be monitored through the afternoon and discharged before dinner. During each of these intervention visits, participants will wear an Omnipod to deliver insulin and a Dexcom G6 Continuous Glucose Monitoring System (CGM) to measure glucose. The closed loop system will receive activity data through a Polar M600 watch worn by the participant. The studies will test the ability of the system to adapt to a missed meal bolus. Participants will eat self selected meals at 10 am and 2pm, both meals with a missed bolus, and these meals will be repeated across both study arms. For one missed meal bolus study, glucose will be controlled using the Robust R-AP closed-loop mode. During the other missed meal bolus study, glucose will be controlled using the MPC closed-loop mode. Participants will complete frequent glucose and ketone checks for safety.

Conditions

• Type 1 Diabetes

Interventions

Type	Name	Description
DEVICE	MPC AP algorithm	The Model Predictive Control (MPC) insulin infusion algorithm contains a model within the controller that takes as an input the aerobic metabolic expenditure in addition to the CGM and meal inputs. The algorithm uses heart rate and accelerometer data collected on the patient's body to calculate metabolic expenditure. The metabolic expenditure then acts on the model for the insulin dynamics, whereby more energy expenditure and longer duration exercise can lead to a more substantial effect of insulin on the CGM.
DEVICE	Robust R-AP algorithm	The R-AP is a modified MPC algorithm. A new feature in the algorithm includes a model for missed meal insulin detection. The model includes estimations for carbohydrate consumption based glucose patterns to determine if that person has consumed a meal without announcing it to the system.

Timeline

• Start date: 2021-12-08
• Primary completion: 2022-03-03
• Completion: 2022-03-03
• First posted: 2021-10-19
• Last updated: 2023-01-20
• Results posted: 2023-01-20

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated device study