This study is exploring a combination of alisertib (a drug that targets cancer cell growth) and endocrine therapy (treatment affecting hormone levels) for patients with a specific type of breast cancer. This cancer is HR-positive (hormone receptor-positive) and HER2-negative (a protein not overproduced in these cancer cells). It's intended for patients whose cancer has come back or spread after trying at least two other hormone therapies. The goal is to find the best dose of alisertib, understand how safe and effective the combination is, and identify which patients might benefit the most.
- Length of Study: Multiple visits are required to determine the optimal dosage.
- Eligibility: Must have tried at least two hormone therapies before.
- Risks: Cannot have had chemotherapy or a specific type of past treatment targeting cancer growth.