A Phase I Study of Niraparib Administered Concurrently With Postoperative RT in Triple Negative Breast Cancer Patients

This research study is a Phase I clinical trial, which tests the safety of an investigational drug and also tries to define the appropriate dose of the investigational drug to use for further studies. "Investigational" means that the drug is being studied. The FDA (the U.S. Food and Drug Administration) has not approved niraparib for this specific disease but it has been approved for other uses. Niraparib is a type of drug called a "PARP inhibitor", which blocks DNA (the genetic material of cells) damage from being repaired or may prevent damage from occurring in the first place. In cancer treatment, inhibiting PARP may help kill cancer cells by not allowing the cancer cells to repair its DNA damage or prevent DNA damage from occurring. This trial is studying people who have triple negative breast cancer because this cancer type is shown to have DNA repair mechanisms that may benefit from combined PARP inhibitor and radiation, and may help prevent recurrence of cancers in the chest wall and lymph nodes of the affected side.