A Phase III Study of ESG401 for Locally Advanced or Metastatic HR+/HER2- Breast Cancer

This Phase 3 study is testing a new cancer drug called ESG401 compared to standard chemotherapy in people with hormone receptor-positive, HER2-negative breast cancer that has spread to other parts of the body and has already been treated with at least one round of chemotherapy. **You may be eligible if...** - You are 18 or older (any gender) - You have HR+/HER2- breast cancer that has spread and stopped responding to chemotherapy - You have at least one measurable tumor on imaging - You are in generally good health (performance score 0–1) - Your blood counts and organ function are adequate **You may NOT be eligible if...** - You have received certain prior therapies including topoisomerase inhibitors or TROP2-targeted treatments - You have untreated or active brain metastases - You have active infections, HIV, or active hepatitis B or C - You had a blood clot, bowel blockage, or gastrointestinal bleeding within the last 6 months - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.