Losartan in Prevention of Radiation-Induced Heart Failure

This is a pilot study examining whether losartan prevents radiation therapy-induced myocardial fibrosis (thickening of the heart tissue), which can cause heart failure, in breast cancer patients receiving radiation therapy.

Losartan is an U.S. Food and Drug Administration (FDA) approved drug used to treat hypertension (high blood pressure) and heart failure. The U.S. Food and Drug Administration (FDA) has not approved losartan for use in the treatment of breast cancer.

The FDA has approved radiation therapy as a treatment option for breast cancer.

The research study procedures include: screening for eligibility and study treatment including evaluations and follow up visits. It is expected participants will be on the study for 1 year.

It is expected that about 10 people will take part in this research study.

Inclusion criteria

->18 years of age

• Non-metastatic Breast Cancer patients who are scheduled to receive conventional left breast/chest wall RT inclusive of treatment to the internal mammary lymph nodes (IMNs)
• Prior chemotherapy is permitted
• Patients must have Left-sided Breast Cancer
• Ability to understand and the willingness to sign a written informed consent document
• No contraindication to MRI

Exclusion criteria

• Person who is pregnant or breastfeeding.
• Patient unable to swallow oral medication.
• Patients receiving any other investigational agent will not be excluded from study eligibility, unless the patient is already enrolled in an interventional study evaluating cardiac toxicity
• Patients already receiving ACE/ARBs.
• Patients with a history of allergic reactions to Losartan biosimilars.