Study on Anastrozole, Fulvestrant, and Abemaciclib for HR+HER2- Metastatic Breast Cancer

Inclusion Criteria

• Must have hormone receptor-positive (HR+) breast cancer, meaning the cancer cells have receptors for estrogen or progesterone.
• Must have newly diagnosed advanced or metastatic breast cancer, or cancer that has returned and cannot be cured with surgery.
• Cancer must have returned more than 12 months after completing previous treatment.
• Must be 18 years or older.
• Must be in relatively good health, with an ECOG performance status of 0 to 2.
• Must be post-menopausal, either naturally or through surgery, or willing to undergo ovarian function suppression if pre-menopausal.
• Must have at least one measurable tumor.
• Must have adequate organ and bone marrow function, as shown by specific blood tests.
• Must be able to swallow pills.
• Must have recovered from any previous chemotherapy side effects, except for hair loss or mild nerve damage.
• Must be able to provide informed consent and follow study procedures.
• Women of childbearing potential and men must agree to use effective birth control during the study and for 90 days after treatment.

Exclusion Criteria

• Cannot have localized breast cancer that can be cured with surgery or radiation.
• Cannot have HER2-positive or triple-negative breast cancer.
• Cannot have inflammatory breast cancer.
• Cannot have had chemotherapy or radiation within 12 months before the study.
• Cannot have been treated with fulvestrant before.
• Cannot be participating in another clinical trial that conflicts with this study.
• Cannot have serious medical conditions that would interfere with the study.
• Cannot have a history of certain heart conditions.
• Cannot have had another cancer unless in complete remission for at least three years.
• Cannot have active infections like HIV or hepatitis.
• Cannot have recently received certain biologic or monoclonal therapies.
• Cannot have allergies to similar drugs used in the study.
• Cannot be pregnant or nursing.