Glucose Metabolism in Cystic Fibrosis Related Diabetes (CFRD)

NCT07102043 | Enrolling By Invitation DMC

• 2 other identifiers: IRB300014949P30DK072482
• Study Type: observational
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

The study aims to test whether use of CFTR modulators (ETI) improves fasting and post prandial glycemia by enhancing disposition index (DI) in individuals with CFRD with CFTR +ve mutation (at least one copy of F508del) on CFTR modulator (ETI) therapy (CFRDF508del+ETI). CFRD with a mutation that is not eligible for modulator therapy (CFRD-ETI) will be the control group.

Conditions

Cystic Fibrosis Related Diabetes

Keywords

Cystic Fibrosis Related Diabetes; cystic fibrosis transmembrane conductance regulator (CFTR); CFTR modulators; Elexacaftor/ tezacaftor/ivacaftor or ETI

Outcome Measures

Primary Outcomes (1)

• Disposition Index in CFRD

  Disposition Index (DI - β-cell responsivity appropriate to the degree of insulin resistance) is higher in CFRDF508del+ETI when compared to CFRD with a mutation not eligible to be on ETI (CFRD-ETI).

  Day 1 During the Mixed meal test

Secondary Outcomes (1)

• Post prandial glucose turnover

  Day 1 During the mixed meal test

Study Arms (2)

CFRD F508del +ETI

CFRD with at least one copy of F508del currently on elexacaftor/tezacaftor/ivacaftor (CFRDF508del+ETI),

CFRD-ETI

CFRD with a mutation that is not eligible for modulator therapy (CFRD-ETI).

Eligibility Criteria

• Age: 21 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Individuals with Cystic Fibrosis related Diabetes (CFRD) Subjects will be recruited from the UAB Health System. Primary locations for recruitment will include the CF center and pulmonary clinics and endocrinology clinics. Dr. Solomon is the Associate Director of the CF center and the Co-Director of the Clinical Research Unit. He will work with the clinical provider team of the adult CF clinic to find eligible patients. All physical recruitment locations are within 5-30 minutes walking/driving distance from the UAB Clinical Research Unit (CRU). Dr. A. Basu, is Director of the Diabetes Technology Clinic at UAB and he sees many of these patients for diabetes care; we also have open communication with the endocrinology and primary care clinics at UAB, where we have had success in the past recruiting for previous and current ongoing studies. Electronically, we will recruit through the UAB Hospital electronic medical record (EMR) system, and UAB internet p

You may qualify if:

• Diagnosis of Cystic Fibrosis Related Diabetes (CFRD)
• Age 21-75 years at time of consent
• BMI 19-50 kg/m2 (In Asians BMI is \~ 2 points lower for comparison so it is 17-48 kg/m2)
• Creatinine ≤ 1.4 mg/dl in women and ≤ 1.5 mg/dl in men
• HbA1c ≤ 11% lifestyle treatment or mono/combination therapy with oral hypoglycemic agents (e.g. metformin or sulphonylurea or SGLT2i) and preferably on insulin pump therapy (i.e., SAP, HCL) with or without CGM will be recruited. However, use of MDI (Multiple Daily Injections) of insulin, i.e., on basal-bolus insulin therapy will also be included. Most of our patients are on insulin therapy with very few on oral antidiabetes medications but we would like to offer them the choice of participation.
• Subjects on FDA approved/recommended full doses of ETI will be offered participation. If dose adjustments of ETI are made after enrollment a discussion will be done with the primary care provider and HCSTOC as required.
• Willing to be at a stable weight for duration of the study.
• An understanding of and willingness to follow the protocol and sign the informed consent

You may not qualify if:

• Debilitating chronic disease
• Anemia \<10.0 gm/dL in females and \<11.0 gm/dL in males
• Symptoms of undiagnosed illness on history/exam
• Abuse of alcohol or recreational drugs
• Pregnancy
• Active hepatic disease (we will include only if less than 3X ULN for liver enzymes and no fibrosis on ultrasound). Transient elevations of liver enzymes will not exclude participation but will be discussed with the primary care provider and HCSTOC as required.
• Current use of the following drugs and supplements:
• i. Corticosteroids ii. Benzodiazepines iii. Opiates iv. Barbiturates v. Anticoagulant therapy vi. Any other medication that the investigator believes is a contraindication to the subject's participation

Sponsors & Collaborators

• University of Alabama at Birmingham: lead
• National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK): collaborator

Study Sites (1)

University of Alabama at Birmingham

Birmingham, Alabama, 352294, United States

Location

Biospecimen

Retention: SAMPLES WITHOUT DNA

Participant biospecimen will be retained until all analysis for outcome measures are complete and results published. DNA will not be extracted retained samples.

Study Officials

• Rita Basu, MD

  UAB Medicine

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: OTHER
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Endowed Professor of Diabetes Science

Study Record Dates

• First Submitted: June 17, 2025
• First Posted: August 3, 2025
• Study Start: May 28, 2026
• Primary Completion (Estimated): May 1, 2028
• Study Completion (Estimated): May 28, 2028
• Last Updated: August 3, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)