Safety of Overestimation of a Meal Insulin Bolus in the Context of Dual-hormone Closed-loop Operation

NCT ID: NCT02626936

Last Updated: 2016-06-10

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: PHASE2
• Total Enrollment: 10 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2016-01-31
• Study Completion Date: 2016-06-30

Brief Summary

In previous studies, investigators have studied if a pre-meal insulin bolus based on estimated carbohydrate meal size would alleviate the burden of carbohydrate counting without a significant degradation in postprandial glucose control. With this strategy, the patient would only have to evaluate the size of the meal in terms of carbohydrate (snack, regular, large or very large) It is however important to establish safety of this simplified meal bolus approach. The safety of overestimating a meal insulin bolus in the context of single and dual-hormone CLS with the simplified meal strategy needs to be determined. Computer simulation will be used to get a reasonable estimate of risks related to over-estimation with single-hormone closed-loop while over-estimation with dual-hormone closed-loop will be tested in adults with type 1 diabètes

Investigators hypothesize that dual-hormone closed-loop with overestimated meal size bolus will not increase time below 4.0 mmol/L compared to dual-hormone closed-loop with an adequately estimated meal size bolus

Conditions

Type 1 Diabetes

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: TREATMENT
• Blinding Strategy: SINGLE

Study Groups

Dual-hormone CL with overestimation of meal size category

A large size standardized meal of 75g of carbohydrates will be provided to the patient and the meal size will be overestimated by one category, which will result in a meal insulin bolus for a meal of 95g of carbohydrates.

Group Type: ACTIVE_COMPARATOR

Dual-hormone closed-loop

Intervention Type: OTHER

Interventions will be undertaken one to 5 days after sensor insertion. Subjects will be admitted at the research center at 7:00 am. Subject's pump will be substituted with the study pump and an additional pump containing glucagon will be installed. At 7:00, CLS will be initiated. At 9:00, a standardized breakfast (75g CHO) will be served. Study subjects will consume the same meal on the two intervention days. During the intervention, patients will be allowed to do sedentary activities. Patients will allowed to consume caffeine during the intervention, but will have to replicate their caffeine consumption on both interventions.The intervention day will end at 13:00.

Insulin

Intervention Type: DRUG

Participant's usual fast-acting insulin analog will be used: Lispro (Humalog), Aspart (NovoRapid) or Glulisine (Apidra)

Glucagon

Intervention Type: DRUG

Glucagon (Eli Lilly) will be used during dual-hormone closed-loop strategy.

Dexcom G4 Platinum glucose sensor

Intervention Type: DEVICE

Accu Chek Combo insulin pump

Intervention Type: DEVICE

Dual-hormone CL with adequate estimation of meal size category

A large size standardized meal of 75g of carbohydrates will be provided to the patient and the meal size will be adequately estimated, which will result in a meal insulin bolus for a meal of 65g of carbohydrates.

Group Type: ACTIVE_COMPARATOR

Dual-hormone closed-loop

Intervention Type: OTHER

Interventions will be undertaken one to 5 days after sensor insertion. Subjects will be admitted at the research center at 7:00 am. Subject's pump will be substituted with the study pump and an additional pump containing glucagon will be installed. At 7:00, CLS will be initiated. At 9:00, a standardized breakfast (75g CHO) will be served. Study subjects will consume the same meal on the two intervention days. During the intervention, patients will be allowed to do sedentary activities. Patients will allowed to consume caffeine during the intervention, but will have to replicate their caffeine consumption on both interventions.The intervention day will end at 13:00.

Insulin

Intervention Type: DRUG

Participant's usual fast-acting insulin analog will be used: Lispro (Humalog), Aspart (NovoRapid) or Glulisine (Apidra)

Glucagon

Intervention Type: DRUG

Glucagon (Eli Lilly) will be used during dual-hormone closed-loop strategy.

Dexcom G4 Platinum glucose sensor

Intervention Type: DEVICE

Accu Chek Combo insulin pump

Intervention Type: DEVICE

Interventions

Dual-hormone closed-loop

Interventions will be undertaken one to 5 days after sensor insertion. Subjects will be admitted at the research center at 7:00 am. Subject's pump will be substituted with the study pump and an additional pump containing glucagon will be installed. At 7:00, CLS will be initiated. At 9:00, a standardized breakfast (75g CHO) will be served. Study subjects will consume the same meal on the two intervention days. During the intervention, patients will be allowed to do sedentary activities. Patients will allowed to consume caffeine during the intervention, but will have to replicate their caffeine consumption on both interventions.The intervention day will end at 13:00.

Intervention Type: OTHER

Insulin

Participant's usual fast-acting insulin analog will be used: Lispro (Humalog), Aspart (NovoRapid) or Glulisine (Apidra)

Intervention Type: DRUG

Glucagon

Glucagon (Eli Lilly) will be used during dual-hormone closed-loop strategy.

Intervention Type: DRUG

Dexcom G4 Platinum glucose sensor

Intervention Type: DEVICE

Accu Chek Combo insulin pump

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

1. Males and females ≥ 18 years old.

2. Clinical diagnosis of type 1 diabetes for at least one year.

3. The subject will have been on insulin pump therapy for at least 3 months and currently using a fast actin insulin analog (Lispro, Aspart or Guilisine).

4. Last (less than 3 months) HbA1c ≤ 10%.

5. Currently using carbohydrate counting as the meal insulin dose strategy.

Exclusion Criteria

1. Clinically significant microvascular complications: nephropathy (estimated glomerular filtration rate below 40 ml/min), neuropathy (especially diagnosed gastroparesis) or severe proliferative retinopathy as judged by the investigator.

2. Recent (< 3 months) acute macrovascular event e.g. acute coronary syndrome or cardiac surgery.

3. Pregnancy.

4. Severe hypoglycemic episode within 1 month of screening.

5. Agents affecting gastric emptying (Motilium®, Prandase®, Victoza®, Byetta® and Symlin®) as well as oral anti-diabetic agents (Metformin, SGLT-2 inhibitors and DPP-4 inhibitors) if not at a stable dose for 3 months. Otherwise, these medications are acceptable and will be kept stable during the entire protocol.

6. Oral steroids unless patients present a low stable dose (e.g. 10 mg or less of prednisone per day or physiological doses, less than 35 mg/day, of hydrocortisone Cortef®). Inhale steroids at stable dose in the last month are acceptable.

7. Other serious medical illness likely to interfere with study participation or with the ability to complete the trial by the judgment of the investigator (e.g. unstable psychiatric condition).

8. Failure to comply with team's recommendations (e.g. not willing to change pump parameters, follow algorithm's suggestions, etc).

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Institut de Recherches Cliniques de Montreal

OTHER

Sponsor Role: lead

Responsible Party

Rémi Rabasa-Lhoret

Associate Professor of Medicine

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Rémi Rabasa-Lhoret

Role: PRINCIPAL_INVESTIGATOR

Institut de recherches cliniques de Montréal

Locations

Institut de recherches cliniques de Montréal

Montreal, Quebec, Canada

Countries

Canada

Other Identifiers

CLASS Safety meal study

Identifier Type: -

Identifier Source: org_study_id