Simplified Meal Approach Using Hybrid Closed-loop Insulin Delivery in Youth and Young Adults With Type 1 Diabetes

NCT05481034 | Completed

• 1 other identifier: SMASH
• Study Type: interventional
• Target: 46
• Locations: 1 country
• Sites: 2

Brief Summary

The purpose of the study is to examine whether a simplified meal approach (as compared to exact carbohydrate counting) can alleviate the need of carbohydrate counting without worsening postprandial control in youth and young adults with type 1 diabetes using hybrid closed-loop insulin delivery with the Cambridge Artificial Pancreas FX System (CamAPS FX system).

Conditions

Type 1 Diabetes

Keywords

Type 1 Diabetes; Youth; Adolescents; Artificial pancreas system; Meal announcement

Outcome Measures

Primary Outcomes (1)

• Percentage of time with sensor glucose measurements between 3.9 and 10.0 mmol/L

  The percentage of time with sensor glucose measurements between 3.9 and 10.0 mmol/L will be compared between both intervention arms. Primary analysis will be carried out according to a non-inferiority framework.

  From the first day of the respective study period to 3 months thereafter

Secondary Outcomes (15)

• Time spent with sensor glucose values above target (>10.0 mmol/L)

  From the first day of the respective study period to 3 months thereafter

• Time spent with sensor glucose values >13.9 mmol/L (%)

  From the first day of the respective study period to 3 months thereafter

• Time spent with sensor glucose measurements < 3.9 mmol/L

  From the first day of the respective study period to 3 months thereafter

• Time spent with sensor glucose measurements < 3.0 mmol/L

  From the first day of the respective study period to 3 months thereafter

• Time spent with sensor glucose measurements between < 3.9 mmol/L and 7.8 mmol/L (%)

  From the first day of the respective study period to 3 months thereafter

Other Outcomes (11)

• Total daily basal insulin dose

  From the first day of the respective study period to 3 months thereafter

• Total daily bolus insulin dose

  From the first day of the respective study period to 3 months thereafter

• Percentage of time of closed-loop operation including engagement with specific functionalities

  From the first day of the respective study period to 3 months thereafter

Study Arms (2)

Simplified carbohydrate estimation first, exact carbohydrate estimation second

EXPERIMENTAL

In the first study period, participants will use the CamAPS FX system and adopt the "simplified meal announcement" (SMA) option to bolus for their meals. SMA comprises the selection of predefined carbohydrate quantities for meal insulin dosing. Meal carbohydrate contents will be set on an individual basis at the baseline visit. In the second study period, Participants will use the CamAPS FX system and insert the estimated grams of carbohydrates into the application as exactly as possible in order to bolus for their meals.

Device: SMA bolus option; Device: Exactly estimated carbohydrate content bolus option

Exact carbohydrate estimation first, simplified carbohydrate estimation second.

EXPERIMENTAL

In the first study period, participants will use the CamAPS FX system and insert the estimated grams of carbohydrates into the application as exactly as possible in order to bolus for their meals. In the second study period, participants will use the CamAPS FX system and adopt the "simplified meal announcement" (SMA) option to bolus for their meals. SMA comprises the selection of predefined carbohydrate quantities for meal insulin dosing. Meal carbohydrate contents will be set on an individual basis at the baseline visit.

Device: SMA bolus option; Device: Exactly estimated carbohydrate content bolus option

Interventions

SMA bolus option DEVICE

SMA comprises the selection of predefined carbohydrate quantities for meal insulin dosing. Meal carbohydrate contents will be set on an individual basis at the baseline visit.

Also known as: Simplified meal announcement bolus option

Exact carbohydrate estimation first, simplified carbohydrate estimation second.; Simplified carbohydrate estimation first, exact carbohydrate estimation second

Exactly estimated carbohydrate content bolus option DEVICE

The carbohydrate content of meals is estimated in grams of carbohydrates prior to a meal bolus

Exact carbohydrate estimation first, simplified carbohydrate estimation second.; Simplified carbohydrate estimation first, exact carbohydrate estimation second

Eligibility Criteria

• Age: 12 Years - 20 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64)

You may qualify if:

• Written informed consent
• Type 1 diabetes as defined by the World Health Organization for at least 6 months
• Age between 12 and 20 years (inclusive)
• Proficient use of continuous glucose monitoring (CGM) or flash glucose monitoring (FGM) for at least 5 days in the past
• Glycated hemoglobin A1c (HbA1c) ≤12%
• The participant is willing to wear closed-loop devices
• The participant is willing to follow study specific instructions
• Negative urine-pregnancy test in sexually active female participants of childbearing potential at screening-visit

You may not qualify if:

• Any physical or psychological disease or condition likely to interfere with the normal conduct of the study and interpretation of the study results
• Known or suspected allergy against insulin
• Participant is pregnant or breast feeding or planning pregnancy within next 6.5 months
• Severe visual impairment
• Severe hearing impairment
• Lack of reliable telephone facility for contact
• Concomitant participation in another trial that interferes with the normal conduct of the study and interpretation of the study results
• Participant not proficient in German

Sponsors & Collaborators

• Lia Bally: lead
• University of Zurich: collaborator

Study Sites (2)

Department of Diabetes, Endocrinology, Nutritional Medicine and Metabolism, Inselspital, Bern University Hospital and University of Bern, Bern, Switzerland

Bern, 3010, Switzerland

Location

Department of Paediatric Endocrinology and Diabetes, University Children's Hospital Zurich

Zurich, 8032, Switzerland

Location

Related Publications (1)

• Laesser CI, Piazza C, Schorno N, Nick F, Kastrati L, Zueger T, Barnard-Kelly K, Wilinska ME, Nakas CT, Hovorka R, Herzig D, Konrad D, Bally L. Simplified meal announcement study (SMASH) using hybrid closed-loop insulin delivery in youth and young adults with type 1 diabetes: a randomised controlled two-centre crossover trial. Diabetologia. 2025 Feb;68(2):295-307. doi: 10.1007/s00125-024-06319-w. Epub 2024 Nov 19.

  PMID: 39560745 DERIVED

MeSH Terms

Conditions

Diabetes Mellitus, Type 1

Condition Hierarchy (Ancestors)

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

Study Officials

• Lia Bally, MD PhD

  University hospital of Bern

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Prof. Dr.med. et Dr. phil.

Study Record Dates

• First Submitted: July 28, 2022
• First Posted: July 29, 2022
• Study Start: January 11, 2023
• Primary Completion: September 29, 2023
• Study Completion: September 29, 2023
• Last Updated: October 18, 2023

Record last verified: 2023-10

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, CSR
• Time Frame: After publication of the study results in a peer-reviewed journal.
• Access Criteria: Contact with and approval by the corresponding author

Locations

CH (2)