Addition of Simvastatin to Dual Anti-HER2 Therapy for the Treatment of HER2-Positive Metastatic Breast Cancer, SIMPHONY Study
This phase II trial studies the effect of adding simvastatin to dual anti-HER2 therapy in treating patients with HER2-positive breast cancer that has spread to other places in the body (metastatic). "HER2 positive" means that the cancer has too many HER2 receptors on the surface of its cells. HER2 receptors act like copy machines, and help tell cancer cells to grow and multiply. HER2-targeted therapies work by blocking the HER2 protein from telling the cell to grow and divide. Once the protein stops working, the cancer cells can no longer make copies of themselves. Once a cancer cell becomes unable to make copies of itself, the tumor will start to shrink. However, some tumors are able to find other ways to make copies of themselves, even when the HER2 protein is blocked. When this happens, the cancer will start to grow again. Simvastatin is used to treat high cholesterol. Adding simvastatin to dual anti-HER2 therapy may cause the cancer to start responding to the HER2-medications and may slow the growth of breast cancer tumors that had been growing on dual HER2-targeted therapy alone or reduce the size of the cancer.