Abemaciclib and Endocrine Therapy in Older Patients With Breast Cancer.

This study is looking at how well abemaciclib (a targeted oral drug) combined with hormone-blocking therapy works in older patients (70+) with hormone receptor-positive, HER2-negative metastatic breast cancer, with a particular focus on maintaining quality of life and physical function. **You may be eligible if...** - You are at least 70 years old - You have metastatic breast cancer that is hormone receptor-positive (estrogen or progesterone receptor positive) and HER2-negative - Your cancer has progressed on prior hormone therapy - You can read and understand English or Spanish - Your life expectancy is more than 6 months **You may NOT be eligible if...** - You have hormone receptor-negative or HER2-positive breast cancer - You have serious heart, liver, or kidney problems - Your cancer has spread to the brain with symptoms - You are on blood thinners that interact with abemaciclib Talk to your doctor to see if this trial is right for you.