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A Study of Olaparib and Pembrolizumab in People with Triple Negative Breast Cancer or Hormone Receptor-Positive HER2-Negative Breast Cancer

Trial Status: closed to accrual

This phase II trial tests whether olaparib and pembrolizumab before standard of care chemotherapy and surgery works to shrink tumors in patients with triple negative or hormone receptor positive, HER2-negative breast cancer. Olaparib is a type of medication called a PARP (poly ADP ribose polymerase) inhibitor. PARP is a protein that helps repair damage to deoxyribonucleic acid (DNA), the genetic material that serves as the body’s instruction book. Changes (mutations) in DNA can cause tumor cells to grow quickly and out of control. But PARP inhibitors have been shown to prevent PARP from working, so tumor cells can’t repair themselves, and they stop growing. Immunotherapy with monoclonal antibodies, such as pembrolizumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. Giving olaparib and pembrolizumab before standard of care chemotherapy and surgery may help shrink and stabilize tumors in patients with triple negative or hormone receptor positive HER2-negative breast cancer.