NCT04530383 · University of Kansas Medical Center
Metformin for People With CFRD on CFTR Modulator Therapy to Improve Ion Channel Function
What this study is about
The purpose of this study is to assess the effectiveness of metformin to improve airway ion channel function in those with CF-related diabetes (CFRD)
View original scientific description
The purpose of this study is to assess the efficacy of metformin to improve airway ion channel function in those with CF-related diabetes (CFRD)
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Age \>18 years with a prior diagnosis of CF.
- Use of ivacaftor or elexacaftor/tezacaftor/ivacaftor or vanzacaftor/tezacaftor/deutivacaftor for 30 days prior to day 0
- Diagnosis of CFRD with evidence of continued glucose intolerance at least 6 months after starting qualifying modulator therapy will be based upon one of the following:
- Insulin use
- Hemoglobin A1C \>6.5%
- Fasting glucose \>126 mg/dl
- Non-fasting glucose \>200 mg/dl (random or as part of a 2-hr OGTT)
Exclusion criteria
- Prior lung or liver transplant
- Use of supplemental oxygen
- CF pulmonary exacerbation requiring hospitalization or intravenous antibiotics in the preceding 30 days
- Systemic corticosteroid or regular non-steroidal anti-inflammatory use in the preceding 30 days
- Cardiac, renal (creatinine clearance \<45 mL/minute), neurologic, psychiatric, endocrine or neoplastic diseases that are judged to interfere with participation in the study
- Alanine aminotransferase, aspartate aminotransferase or alkaline phosphatase \>1.5X the upper limit of normal; bilirubin \>3 mg/dL
- Taking medications that interact with metformin.
- Vitamin B12 deficiency
- Pregnancy or lactation
- Inability or unwillingness to comply with an approved contraceptive method during the study period (females of childbearing age)
- Use of medications known to be strong CYP inducers or moderate to strong CYP inhibitors
- In the opinion of the investigator any severe or acute or chronic condition or laboratory abnormality that may increase the risk associated with trial participation or make the subject inappropriate for enrollment
- Participation in another interventional trial that, in the opinion of the investigator, has the potential to affect the primary outcome
Where
- Kansas City, Kansas
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Apr 15, 2026 · Source of record for eligibility and locations