A Study of Chidamide Plus Endocrine in Maintenance Treatment of HR+/HER2- Breast Cancer After First-line Chemotherapy

This study tests whether adding chidamide (a drug that affects gene regulation) to hormone therapy can help maintain remission in women with hormone receptor-positive, HER2-negative breast cancer after completing first-line chemotherapy. **You may be eligible if...** - You are a woman aged 18–70 - You have HR+/HER2- breast cancer confirmed by biopsy - Your cancer is locally advanced or has spread to distant organs - You have completed first-line chemotherapy and achieved at least stable disease **You may NOT be eligible if...** - You have HER2-positive breast cancer - You have not responded to or completed first-line chemotherapy - You are outside the 18–70 age range Talk to your doctor to see if this trial is right for you.