Actively Recruiting
Metformin for the Treatment of Insulin Resistance in Women With Stage I-III Breast Cancer Completing Chemotherapy
Led by City of Hope Medical Center · Updated on 2026-01-22
200
Participants Needed
3
Research Sites
234 weeks
Total Duration
On this page
Sponsors
C
City of Hope Medical Center
Lead Sponsor
N
National Cancer Institute (NCI)
Collaborating Sponsor
AI-Summary
What this Trial Is About
This phase III trial evaluates how often women develop insulin resistance and type-2 diabetes and compares metformin with usual care to usual care alone in treating insulin resistance in women with stage I-III breast cancer after chemotherapy. Insulin resistance occurs when cells stop responding to insulin and is a risk factor for developing diabetes and heart disease. Higher levels of insulin have been shown to be associated with aggressive breast cancer. Metformin hydrochloride decreases the amount of glucose (a type of sugar) released into the bloodstream from the liver and increases the body's use of the glucose. Metformin as well as standard of care diet and exercise education is known to lower blood sugar. However, chemotherapy may accelerate metabolic disorders, such as high blood sugar, and the impact of metformin in these breast cancer survivors is not known. Giving metformin with usual care may be more effective than usual care alone in preventing or reversing insulin resistance in women with stage I-III breast cancer after chemotherapy.
CONDITIONS
Official Title
Metformin for the Treatment of Insulin Resistance in Women With Stage I-III Breast Cancer Completing Chemotherapy
Who Can Participate
Eligibility Criteria
You may qualify if you...
- Documented informed consent of the participant and/or legally authorized representative
- Agreement to allow lab draw of approximately 26 mL of blood
- Age 18 years or older
- Female sex assigned at birth
- Ability to read and understand English or Spanish for questionnaires
- Diagnosis of estrogen receptor (ER)-negative /HER2-wild type or -amplified invasive mammary carcinoma stages I-III
- Received systemic treatment for breast cancer
- Completed treatment for stage I-III breast cancer within 90 days to 5 years and are disease free
- Women who receive drugs for weight loss (e.g., semaglutide) prior to diagnosis are eligible and can continue during the intervention
You will not qualify if you...
- Currently taking metformin or any other oral antidiabetic medications
- Taking tamoxifen or aromatase inhibitor
- Contraindication to metformin such as acute hypersensitivity or allergic reaction
- Acute or chronic renal insufficiency (GFR < 30 mL/min/1.73m2) or acute renal insufficiency due to hepato-renal syndrome or peri-operative liver transplantation period
- Previously diagnosed type 1 or type 2 diabetes
- Pregnant or within 1 year of pregnancy and completion of lactation
- Other active malignancy that may interfere with study safety or efficacy assessment
- Any condition that contraindicates participation due to safety concerns
- Employment under direct/indirect supervision of the principal investigator or study team
- Inability to comply with all study procedures due to feasibility or logistics issues
AI-Screening
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Trial Site Locations
Total: 3 locations
1
City of Hope Medical Center
Duarte, California, United States, 91010
Actively Recruiting
2
UC San Diego Moores Cancer Center
La Jolla, California, United States, 92093
Not Yet Recruiting
3
University of California-Riverside
Riverside, California, United States, 92521
Not Yet Recruiting
How is the study designed?
Study Type
INTERVENTIONAL
Masking
NONE
Allocation
RANDOMIZED
Model
PARALLEL
Primary Purpose
SUPPORTIVE_CARE
Number of Arms
2
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