Trial of Ra-223 Dichloride in Combination With Hormonal Therapy and Denosumab in the Treatment of Patients With Hormone-Positive Bone-Dominant Metastatic Breast Cancer

Study Drug Administration: If you are found to be eligible to take part in this study, you will receive Ra-223 dichloride by vein over no more than 1 minute on Day 1 of each 28-day study cycle. You will also receive denosumab as an injection under the skin on Day 1 of Cycles 1- 6. You will also receive hormone therapy while on study. Your doctor will discuss with you what type of hormone therapy you will have, how it will be given, and its risks. Study Visits: On Day 1 of Cycle 1, blood (about 2 teaspoons) will be drawn for routine tests. On Day 1 of Cycles 2-5: * You will have a physical exam. * Blood (about 2 teaspoons) will be drawn for routine tests. On Day 1 of Cycle 6: * Blood (about 2 teaspoons) and urine will be collected for routine tests. * Blood (about 3 tablespoons) will be drawn for biomarker testing, including genetic biomarkers. * Blood (about 5 teaspoons) will be drawn to test for CTCs, tumor markers, and genetic testing. * You will have a PET-CT scan and a bone scan to check the status of the disease. If the doctor thinks it is needed, you will also have an MRI. Length of Study Participation: You may continue taking the study drugs for up to 6 cycles. You will no longer be able to take the study drug if the disease gets worse, if intolerable side effects occur, or if you are unable to follow study directions. Your participation will be over after the end-of-study visit. End-of-Study Visit: After your last dose of study drug: * You will have a physical exam. * Blood (about 2 teaspoons) and urine will be collected for routine tests. * Blood (about 3 tablespoons) will be drawn for biomarker testing, including genetic biomarkers. * Blood (about 5 teaspoons) will be drawn to test for CTCs, tumor markers, and genetic testing. * You will have a PET-CT scan and either a bone scan or a CT scan to check the status of the disease. If the doctor thinks it is needed, you will also have an MRI. * If the doctor thinks it is needed, you will have a bone marrow aspiration/biopsy to check the status of the disease.