Diabetes Closed-Loop Project 6 (DCLP6): Fully Automated Closed-Loop Control in Type 1 Diabetes Using Meal Anticipation

Not Applicable

Completed

Conditions: Type 1 Diabetes

Interventions: Device: Fully Closed Loop with meal anticipation module (FCL+)
Device: Hybrid Closed Loop (HCL)
Device: Fully Closed Loop (FCL)

Registration Number: NCT04877730

Lead Sponsor: University of Virginia

Brief Summary: The purpose of this study is to test the meal anticipation module on a closed loop algorithm, assessing efficacy and safety.

Detailed Description: This is a pilot study to assess glycemic responses to three different approaches to insulin dosing for carbohydrate ingestion, with different approaches to a closed-loop system in random order;

1. without the meal anticipation module and without carbohydrate announcement (FCL)

2. with the meal anticipation module and without carbohydrate announcement (FCL+)

3. without the meal anticipation module and with carbohydrate announcement (HCL),

This study will target completion of up to 36 adults in a randomized cross-over trial, comparing blood glucose time in range 70-180 mg/dL following meals with and without the meal anticipation module in use (FCL+ vs FCL), and comparing to a system with carb announcement instead of a meal anticipation module (HCL). The study will also assess safety when dinner is consumed later than usual and when a lunch is consumed without having been entrained in the meal anticipation module. Each participant will complete each of the 3 modules in random order.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 50

Inclusion Criteria

Age ≥18.0 and ≤70 years old at time of consent
Clinical diagnosis, based on investigator assessment, of type 1 diabetes for at least one year
Currently using insulin for at least six months
Currently using insulin pump for at least three months
Using insulin parameters such as carbohydrate ratio and correction factors consistently on their pump in order to dose insulin for meals or corrections
Access to internet and willingness to upload data during the study as needed
For females, not currently known to be pregnant or breastfeeding
If female and sexually active, must agree to use a form of contraception to prevent pregnancy while a participant in the study. 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 suspend use of any personal CGM for the duration of the clinical trial once the study CGM is in use
Willingness to use the University of Virginia (UVa) closed-loop system throughout study admission
Willingness to use the insulin supplied by the study for the hotel stay, if not already using that preparation. Study insulin will be lispro (Humalog) or aspart (Novolog)
Willingness not to start any new non-insulin glucose-lowering agent during the course of the trial (including metformin, GLP-1 agonists, pramlintide, DPP-4 inhibitors, biguanides, sulfonylureas and naturaceuticals)
Willingness to eat at least 1g/kg of carbohydrate per day during the hotel admission
Willingness to reschedule if placed on oral steroids
An understanding and willingness to follow the protocol and signed informed consent
Willingness to commit to self-quarantine for at least 5 days before COVID-19 testing (If participant has received a full course of COVID-19 vaccine and data emerge suggesting significantly reduced transmissibility among those receiving that vaccine, this self-quarantine requirement can be waived.)

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 being treated for a seizure disorder
Planned surgery during study duration
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.
Use of an automated insulin delivery mechanism that is not downloadable by the subject or study team
Known contact with a COVID-19 positive individual within 14 days of the hotel/rental house studies.

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
FCL+ (Fully Closed Loop with meal anticipation)	Fully Closed Loop with meal anticipation module (FCL+)	Closed-loop control with meal anticipation module without meal bolus
HCL (Hybrid Closed Loop)	Hybrid Closed Loop (HCL)	Closed-loop control without meal anticipation module with meal bolus
FCL (Fully Closed Loop)	Fully Closed Loop (FCL)	Closed-loop control without meal anticipation module without meal bolus

Primary Outcome Measures

Name	Time	Method
Time in Range (TIR) 70-180 mg/dL From Breakfast Time + 5 Hours	The 5 hour period following breakfast during the study admission	Frequency of CGM values falling between 70 mg/dL and 180mg/dL (included) in the 5 hours following breakfast. Higher TIR is a positive outcome.

Secondary Outcome Measures

Name	Time	Method
Time Below Range (TBR) From Lunch Time + 5 Hours	The 5 hour period following lunch during the study admission	Frequency of CGM values falling below 70 mg/dL (excluded) in the 5 hours following lunch.
Time in Significant Hypoglycemia Dinner Time + 5 Hours	The 5 hour period following dinner during the study admission	Frequency of CGM values falling below 54 mg/dL (excluded) in the 5 hours following dinner.
Time in Range (TIR) 70-180 mg/dL Overall	The 24 hour study admission from 4pm to 4pm	Frequency of CGM values falling between 70 mg/dL and 180mg/dL (included) during the 24hr study admission. Higher TIR is a positive outcome.
Time Above Range (TAR) From Dinner Time + 5 Hours	The 5 hour period following dinner during the study admission	Frequency of CGM values falling above 180 mg/dL (excluded) in the 5 hours following dinner.
Time in Significant Hyperglycemia Overall	The 24 hour study admission from 4pm to 4pm	Frequency of CGM values falling above 250 mg/dL (excluded) during the 24hr study admission.
Time in Range (TIR) 70-180 mg/dL From Dinner Time + 5 Hours	The 5 hour period following dinner during the study admission	Frequency of CGM values falling between 70 mg/dL and 180mg/dL (included) in the 5 hours following dinner. Higher TIR is a positive outcome.
Time Above Range (TAR) Overall	The 24 hour study admission from 4pm to 4pm	Frequency of CGM values falling above 180 mg/dL (excluded) during the 24hr study admission.
Time in Range (TIR) 70-180 mg/dL From Lunch Time + 5 Hours	The 5 hour period following lunch during the study admission	Frequency of CGM values falling between 70 mg/dL and 180mg/dL (included) in the 5 hours following lunch. Higher TIR is a positive outcome.
Time Below Range (TBR) From Breakfast Time + 5 Hours	The 5 hour period following breakfast during the study admission	Frequency of CGM values falling below 70 mg/dL (excluded) in the 5 hours following breakfast.
Time Below Range (TBR) Overall	The 24 hour study admission from 4pm to 4pm	Frequency of CGM values falling below 70 mg/dL (excluded) during the 24hr study admission.
Time Below Range (TBR) From Dinner Time + 5 Hours	The 5 hour period following dinner during the study admission	Frequency of CGM values falling below 70 mg/dL (excluded) in the 5 hours following dinner.
Time Above Range (TAR) From Breakfast Time + 5 Hours	The 5 hour period following breakfast during the study admission	Frequency of CGM values falling above 180 mg/dL (excluded) in the 5 hours following breakfast.
Time in Significant Hyperglycemia From Breakfast Time + 5 Hours	The 5 hour period following breakfast during the study admission	Frequency of CGM values falling above 250 mg/dL (excluded) in the 5 hours following breakfast.
Time in Significant Hyperglycemia From Dinner Time + 5 Hours	The 5 hour period following dinner during the study admission	Frequency of CGM values falling above 250 mg/dL (excluded) in the 5 hours following dinner.
Time in Significant Hyperglycemia From Lunch Time + 5 Hours	The 5 hour period following lunch during the study admission	Frequency of CGM values falling above 250 mg/dL (excluded) in the 5 hours following lunch.
Time in Significant Hypoglycemia From Breakfast Time +5 Hours	The 5 hour period following breakfast during the study admission	Frequency of CGM values falling below 54 mg/dL (excluded) in the 5 hours following breakfast.
Time in Significant Hypoglycemia Lunch Time + 5 Hours	The 5 hour period following lunch during the study admission	Frequency of CGM values falling below 54 mg/dL (excluded) in the 5 hours following lunch
Time Above Range (TAR) From Lunch Time + 5 Hours	The 5 hour period following lunch during the study admission	Frequency of CGM values falling above 180 mg/dL (excluded) in the 5 hours following lunch.
Time in Significant Hypoglycemia Overall	The 24 hour study admission from 4pm to 4pm	Frequency of CGM values falling below 54 mg/dL (excluded) during the 24hr study admission.
Number of Hypoglycemia Events From Breakfast Time + 5 Hours	The 5 hour period following breakfast during the study admission	Number of hypoglycemia events in the 5 hours following breakfast. A hypoglycemia event is defined as at least two consecutive CGM values \<70mg/dL or a hypoglycemia treatment (two events separated by less than 30 minutes are counted as one). Metrics are number of hypoglycemia events per participant.
Number of Hypoglycemia Events Dinner Time + 5 Hours	The 5 hour period following dinner during the study admission	Number of hypoglycemia events in the 5 hours following dinner. A hypoglycemia event is defined as at least two consecutive CGM values \<70mg/dL or a hypoglycemia treatment (two events separated by less than 30 minutes are counted as one). Values reported as the number of hypoglycemia events per participant.
Number of Hypoglycemia Events Overall	The 24 hour study admission from 4pm to 4pm	Number of hypoglycemia events during the 24hr study admission. A hypoglycemia event is defined as at least two consecutive CGM values \<70mg/dL or a hypoglycemia treatment (two events separated by less than 30 minutes are counted as one). Values reported as the number of hypoglycemia events per participant.
Number of Hypoglycemia Events Lunch Time + 5 Hours	The 5 hour period following lunch during the study admission	Number of hypoglycemia events in the 5 hours following lunch. A hypoglycemia event is defined as at least two consecutive CGM values \<70mg/dL or a hypoglycemia treatment (two events separated by less than 30 minutes are counted as one).
Units of Insulin Injected Between 2 Hours Before and 5 Hours After Breakfast	The 7 hour period including the two hours before and the 5 hours after breakfast	Sum of all system provided insulin for breakfast (as planned) post-prandial excursion, including anticipation
Units of Insulin Injected (Units/kg) Overall	The 24 hour study admission from 4pm to 4pm	Calculation of all system-provided insulin (units/kg) injected during the 24hr study admission.
Units of Insulin Injected Between 2 Hours Before and 5 Hours After Dinner	The 7 hour period including the 2 hours before and 5 hours after dinner	Sum of all system provided insulin for dinner (late) post-prandial excursion, including anticipation