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Completed

NCT Number: NCT01519102

Comparison of Closed-loop Operation After Morning Meal With and Without Carbohydrate Counting

Closed-loop strategy is composed of three components: glucose sensor to read glucose levels, insulin pump to infuse insulin and a dosing mathematical algorithm to decide on the required insulin dosage based on the sensor's readings. A dual-hormone closed-loop system would regulate glucose levels through the infusion of two hormones: insulin and glucagon.

The main goal of this project is to assess whether a dual-hormone closed-loop strategy would alleviate the burden of carbohydrate counting from patients with type 1 diabetes (T1D) without a significant degradation in post-meal glucose control.

Each patient will be admitted twice to a clinical research facility. In one visit, patients will eat a morning meal accompanied with a matching insulin bolus (depending on the carbohydrate content of the meal) and glucose levels will be subsequently regulated using dual-hormone closed-loop system. In the other visit, patients will eat the same meal but will inject only a partial insulin bolus (not depending on carbohydrate content of the meal) and the remaining needed insulin will be delivered based on glucose sensor excursions as part of closed-loop operation. If post-meal glucose levels were indifferent between the two visits, then this would suggest that carbohydrate counting may not be necessary during closed-loop operation as the closed-loop system will give any remaining insulin needed to cover the glucose absorbed from the meal. Twelve subjects will be enrolled in this study.

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Key information

Conditions

Type-1 Diabetes

Age range

18 year–65 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 2

Primary location

Institut de Recherches Cliniques de Montréal (IRCM)

Montreal, Quebec, H2W 1R7, Canada

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Males and females ≥ 18 and ≤ 65 years of old.
  • Clinical diagnosis of type 1 diabetes for at least one year. The diagnosis of type 1 diabetes is based on the investigator's judgment and medical history (e.g. history of acido-ketosis, etc.); C peptide level and antibody determinations are not needed.
  • The subject will have been on insulin pump therapy for at least 3 months.
  • Last (less than 3 months) HbA1c ≤ 12%.

Exclusion criteria

  • Clinically significant nephropathy, neuropathy (especially clinically significant gastroparesis) or retinopathy as judged by the investigator.
  • Recent (< 3 months) acute macrovascular event e.g. acute coronary syndrome or cardiac surgery.
  • Pregnancy.
  • Severe hypoglycemic episode within two weeks of screening.
  • Medication likely to affect with the interpretation of the results: Prandase, Victoza, Byetta and Symlin
  • Known or suspected allergy to the trial products or meal contents.
  • Other 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 team's recommendations (e.g. not willing to eat snack, not willing to change pump parameters, etc).
  • Unreliable carbohydrate counting
  • Problems with venous access

Treatment and study plan

Dual Hormone closed-loop system

Device

The closed-loop system is composed of three components: continuous glucose system, insulin infusion pumps that infuses insulin and glucagon and a control algorithm that decides on the infusion rates based on sensor readings.

Primary outcomes

  1. Incremental area under the curve of plasma glucose concentration as compared to pre-meal glucose value of the postprandial glucose excursions

    Time frame: 0-300min

Secondary outcomes

  1. Percentage of postprandial time of plasma glucose concentrations spent in the high range (above 10.0 mmol/l).

    Time frame: 0-300 min

  2. Mean plasma glucose concentration.

  3. Total insulin delivery

  4. Total glucagon delivery

  5. Plasma glucose concentration and incremental plasma glucose concentration at 2 hours postmeal

  6. Postprandial peak and incremental postprandial peak of plasma glucose concentration

  7. Percentage of time of plasma glucose concentrations spent in target range. Target range is defined to be between 4.0 and 10.0 mmol/l for 150 minutes postmeal and between 4.0 and 8.0 mmol/l afterwards

  8. Percentage of postprandial time of plasma glucose concentrations spent in the low range (below 4.0mmol/l)

    Time frame: 0-300min

Sponsors and collaborators

Lead sponsor

Institut de Recherches Cliniques de Montreal

Other

Collaborators

  • McGill University
  • Montreal Children's Hospital of the MUHC

Registry information

Official study title

An Open-label, Randomized Two-way, Cross-over Study to Compare Meal-and-carbohydrate-announcement Strategy Versus Meal-announcement Strategy During Closed-loop Regulation of Glucose Levels in a Morning Meal in Adults With Type-1 Diabetes.

Acronym: CLASS02

Important dates

Study start
2012
Primary completion
2012
Study completion
2012
First posted
Jan 26, 2012
Registry last updated
Dec 10, 2012

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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