Comparison of Meal-Time Dosing of Insulin in Cystic Fibrosis Related Diabetes

NCT04533646 | Completed Phase 4 Results FDA Drug

• 1 other identifier: STUDY20060197
• Study Type: interventional
• Target: 13
• Locations: 1 country
• Sites: 1

Brief Summary

The aim of this study is to assess the utility of CGMs to determine the optimal method to dose meal-time insulin. The investigators will examine glucose excursions in patients with CF who will dose meal-time rapid-acting insulin by carbohydrate counting versus fixed-dose rapid-acting insulin. The carbohydrate ratio and fixed doses will be determined by existing doses, total daily insulin doses, body weight, and insulin sensitivity along with predisposition to hypoglycemia. Bolus insulin dosing is an important part of CFRD management due to the high nutritional demands of these patients. If dosed incorrectly, this could lead to marked hyperglycemia and could worsen nutritional status due to urinary glucose losses. In this project, the investigators will perform a within-subjects' comparison of the 2 standard methods of meal-time rapid-acting insulin dosing.

Conditions

Cystic Fibrosis-related Diabetes

Outcome Measures

Primary Outcomes (1)

• Time in Target

  Measurement of percentage of time in target of glucose level

  2 weeks

Secondary Outcomes (1)

• Hypoglycemia

  2 weeks

Study Arms (1)

Fixed Dosing, Followed by Carbohydrate Counting

EXPERIMENTAL

Dosing of premeal insulin with fixed doses

Drug: Insulin; Device: Continuous glucose monitor (CGM)

Interventions

Insulin DRUG

Participants will be asked to dose insulin during the first week using fixed doses. During the second week of the study, participants will dose insulin based on carbohydrate counting. Blood sugar control will be compared between the 2 weeks to determine the outcomes of the study.

Fixed Dosing, Followed by Carbohydrate Counting

Continuous glucose monitor (CGM) DEVICE

Participants will be required to wear a CGM to measure glucose trends

Fixed Dosing, Followed by Carbohydrate Counting

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age \>18 age of years
• Diagnosis of cystic fibrosis related diabetes
• Using basal bolus insulin
• Cystic Fibrosis with Lung Transplantation

You may not qualify if:

• Use of continuous glucose monitors
• Patient unable to check fingerstick blood sugars

Sponsors & Collaborators

• Jagdeesh Ullal: lead
• Wake Forest University Health Sciences: collaborator

Study Sites (1)

University of Pittsburgh Medical Center, Center for Diabetes and Endocrinology

Pittsburgh, Pennsylvania, 15213, United States

Location

MeSH Terms

Interventions

Insulin

Intervention Hierarchy (Ancestors)

Proinsulin; Insulins; Pancreatic Hormones; Peptide Hormones; Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists; Peptides; Amino Acids, Peptides, and Proteins

Results Point of Contact

• Title: Associate Professor of Medicine
• Organization: University of Pittsburgh Medical Center

ullalj@upmc.edu

4125869700

Study Officials

• Jagdeesh Ullal, MD

  University of Pittsburgh Medical Center

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Clinical Associate Professor

Model Details: This study design involves a within-subjects comparison using a sequential cross over that occurs over a 2-week time frame. During the first seven days of wear, the participants will be asked to dose their mealtime rapid-acting insulin by fixed-dose, and the next seven days, participants will be asked to dose their mealtime rapid-acting insulin by carbohydrate counting. After the 14 days, participants will return their continuous glucose monitor (CGM) devices for analysis and interpretation.

Study Record Dates

• First Submitted: August 23, 2020
• First Posted: August 31, 2020
• Study Start: September 15, 2020
• Primary Completion: July 31, 2023
• Study Completion: September 1, 2025
• Last Updated: October 15, 2025
• Results First Posted: March 19, 2025

Record last verified: 2025-10

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)