Phase II Study of Metformin for Reduction of Obesity-Associated Breast Cancer Risk
Status:
Active, not recruiting
Trial end date:
2022-06-30
Target enrollment:
Participant gender:
Summary
Overweight and obesity are well established risk factors for breast cancer that develop after
menopause. The increased postmenopausal breast cancer risk in women who are overweight or
obese is likely to be attributed to multiple metabolic disturbances. Metformin is a commonly
used medication in diabetics to stabilize blood sugar. Association studies and laboratory
studies have shown its potential to reduce the risk for development of cancer, including
breast cancer. Recent pilot clinical studies in breast cancer patients suggest that metformin
may only be effective in overweight or obese women with metabolic disturbances. We propose to
conduct a clinical study of metformin in overweight or obese premenopausal women with
metabolic disturbances. Study participants will be randomly assigned to receive metformin or
placebo for 12 months. The study will evaluate whether metformin can result in favorable
changes in risk features that have been associated with increased breast cancer risk. The
risk features that will be examined in our study include breast density, certain proteins and
hormones, products of body metabolism, and body weight and composition. The study should help
determine the potential breast cancer preventive activity of metformin in a growing
population at risk for multiple diseases.