Tirzepatide for Weight Loss Intervention in Early-Stage Hormone Receptor Positive/HER2 Negative Breast Cancer

The primary objective of this clinical trial is to determine the proportion of patients who achieve a 5% or greater reduction in body weight by the end of the study treatment with tirzepatide, during adjuvant treatment for hormone receptor-positive, HER2-negative (HR+/Her2-) breast cancer. Secondary objectives include assessing the safety and tolerability of tirzepatide for weight loss during this treatment. The feasibility of using tirzepatide for weight loss intervention will be evaluated through discontinuation rates and completion of the treatment course. Additionally, the trial will determine the 3-year invasive disease-free survival (IDFS) and 3-year distant relapse-free survival (DRFS) with the use of tirzepatide. The study will also assess changes in Body Mass Index (BMI), body fat distribution (measured via Waist/Hip Ratio (WHR) and waist circumference), and obesity-related metabolic markers (including Blood Pressure, fasting insulin, fasting blood glucose, HgbA1c, cholesterol, LDL, HDL, triglycerides, IGF1, estrogen, and testosterone). Finally, the trial will monitor for circulating tumor DNA (ctDNA) and assess changes when using tirzepatide for weight loss in the adjuvant treatment of HR+/Her2- breast cancer. Quality of Life assessments will be obtained and exploratory objectives investigating adipokines (adiponectin, leptin) and their receptors, metabolomic pathways and immune cell metabolism will be conducted.