Three-way, Cross-over Closed-loop Exercise Study

NCT02241889 | Completed Results

• 1 other identifier: DP3-2014
• Study Type: interventional
• Target: 23
• Locations: 1 country
• Sites: 1

Brief Summary

Blood glucose control systems that utilize both insulin and glucagon to manage blood sugar are paving the way to revolutionize the management of this disease. The benefit of improved control of blood sugar levels compared to standard insulin pump therapy has already been demonstrated. However, the risk of low blood sugar in type 1 diabetes increases considerably during exercise. The investigators research group has shown that small doses of glucagon can prevent low blood sugar when used in a blood sugar control system in patients with type 1 diabetes. However, as insulin sensitivity changes occur very rapidly during exercise, the ability to recognize the onset of physical activity in order to appropriately adjust the insulin and glucagon delivery is vital to helping prevent exercise-induced hypoglycemia. The purpose of this study is to test how well a new modified blood sugar control system controls blood sugar during exercise compared to: 1) the current system without modifications and 2) standard insulin pump therapy.

Conditions

Type 1 Diabetes

Keywords

diabetes; closed-loop; bi-hormonal; exercise

Outcome Measures

Primary Outcomes (2)

• Percent of Time With Sensed Glucose < 70 mg/dl

  Assess the percent of time that the Dexcom G4 or G4 Share reported sensor glucose values less than 70 mg/dl using Dexcom sensor downloads.

  from start of exercise (~hour 12) until study completion (hour 21)

• Percent of Time With Sensed Glucose Between 70-180 mg/dl

  Assess the percent of time that the Dexcom G4 or G4 Share reported sensor glucose values between 70-180 mg/dl using Dexcom sensor downloads.

  from start of exercise (~hour 12) until study completion (hour 21)

Secondary Outcomes (8)

• Mean of the Mean Sensed Glucose Per Participant

  Entire 21 hour study duration excluding the first four hours

• Number of Carbohydrate Treatments

  Entire 21 hour study duration excluding the first four hours

• Percent of Time With Sensed Glucose < 50 mg/dl

  Entire 21 hour study duration excluding the first four hours

• Percent of Time With Sensed Glucose > 180 mg/dl

  Entire 21 hour study duration excluding the first four hours

• Number of Events Capillary Blood Glucose (CBG) <70 mg/dl

  Entire 21 hour study duration excluding the first four hours

Study Arms (3)

Standard Insulin Pump Therapy

ACTIVE COMPARATOR

Subjects will undergo 21 hour study with exercise using Insulin pump therapy and managing their blood glucose as they normally would.

Device: Insulin pump therapy

Closed-loop without adjustment

EXPERIMENTAL

Subjects will undergo 21 study using the Closed-loop Artificial Pancreas Controller to manage blood sugar. Exercise will not be annouced to the controller and no adjustments to insulin and glucagon delivery will be made.

Device: Closed-loop Artificial Pancreas Controller

Closed-loop with adjustment

EXPERIMENTAL

Subjects will undergo 21 hour study using the Closed-loop Artificial Pancreas Controller to manage blood sugar. Exercise will be annouced to the controller and adjustments to insulin and glucagon delivery will be made.

Device: Closed-loop Artificial Pancreas Controller

Interventions

Insulin pump therapy DEVICE

Subject's own insulin pump will be used to manage blood glucose.

Standard Insulin Pump Therapy

Closed-loop Artificial Pancreas Controller DEVICE

Closed-loop Artificial Pancreas Controller includes insulin and glucagon delivery algorithm implemented on a smart phone, utilizing sensor glucose values from a Dexcom G4 sensor and sending delivery commands to two Tandem t:slim insulin pumps, one filled with insulin and one with glucagon.

Closed-loop with adjustment; Closed-loop without adjustment

Eligibility Criteria

• Age: 21 Years - 45 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Diagnosis of type 1 diabetes mellitus for at least 1 year.
• Male or female subjects 21 to 45 years of age.
• Physically willing and able to perform 45 min of exercise (as determined by the investigator after reviewing the subjects activity level)
• Current use of an insulin pump.
• Willingness to follow all study procedures, including attending all clinic visits.
• Willingness to sign informed consent and HIPAA documents.

You may not qualify if:

• Female of childbearing potential who is pregnant or intending to become pregnant or breast-feeding, or is not using adequate contraceptive methods. Acceptable contraception includes birth control pill / patch / vaginal ring, Depo-Provera, Norplant, an IUD, the double barrier method (the woman uses a diaphragm and spermicide and the man uses a condom), or abstinence.
• Renal insufficiency (GFR \< 60 ml/min, using the MDRD equation as report by the OHSU laboratory).
• Impaired liver function, defined as AST or ALT ≥2.5 times upper limit of normal, according to OHSU laboratory reference ranges.
• Hematocrit of less than or equal to 34%.
• History of severe hypoglycemia during the past 12 months prior to screening visit or hypoglycemia unawareness as judged by the investigator.
• Adrenal insufficiency.
• Any active infection.
• Known or suspected abuse of alcohol, narcotics, or illicit drugs.
• Seizure disorder.
• Active foot ulceration.
• Severe peripheral arterial disease characterized by ischemic rest pain or severe claudication.
• Major surgical operation within 30 days prior to screening.
• Use of an investigational drug within 30 days prior to screening.
• Chronic usage of any immunosuppressive medication (such as cyclosporine, azathioprine, sirolimus, or tacrolimus).
• Bleeding disorder, treatment with warfarin, or platelet count below 50,000.

Sponsors & Collaborators

• Oregon Health and Science University: lead

Study Sites (1)

Oregon Health and Science University

Portland, Oregon, 97239, United States

Location

MeSH Terms

Conditions

Diabetes Mellitus, Type 1; Diabetes Mellitus; Motor Activity

Condition Hierarchy (Ancestors)

Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Endocrine System Diseases; Autoimmune Diseases; Immune System Diseases; Behavior

Results Point of Contact

• Title: Dr. Jessica Castle
• Organization: Oregon Health and Science University

castleje@ohsu.edu

503-494-7072

Study Officials

• Jessica Castle, MD

  Oregon Health and Science University

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Study Record Dates

• First Submitted: September 12, 2014
• First Posted: September 16, 2014
• Study Start: January 1, 2015
• Primary Completion: September 1, 2015
• Study Completion: September 1, 2015
• Last Updated: May 22, 2017
• Results First Posted: May 22, 2017

Record last verified: 2017-04

Locations

US (1)