SIMPHONY: A Trial Adding Simvastatin to Dual Anti-HER2 Therapy in Patients with HER2-positive Metastatic Breast Cancer (H-41818)

The purpose of this study is to find out if adding simvastatin (an oral medication approved by the FDA to treat high cholesterol) to dual anti-HER2 treatment can slow down the growth or reduce the size of your cancer.

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, and the tumor begins 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. Researchers believe that adding simvastatin to your current anti-HER2 therapy regimen may cause your cancer to start responding to the HER2 medications you are already receiving.