We are doing this study to find out if an experimental drug called asciminib (the study drug) is a safe and effective option for people with metastatic HER2+ breast cancer with brain metastases when it is combined with trastuzumab.

HER2+ Breast Cancer with Brain Metastases

Adults ages 18+ who:

• Are diagnosed with HER2+ breast cancer that has metastases to the brain
• Have been previously treated with at least 1 line of therapy

For more information, contact the study team at breastcl@dm.duke.edu.

If you choose to join this study, you will get a combination of the study drug and the standard of care drug, trastuzumab. You will continue to take this study combination until you stop receiving a positive benefit or your doctor thinks it is no longer necessary to continue the study regimen.

The study drug is a tyrosine kinase inhibitor that works by blocking enzymes to prevent cancer cells from growing. Trastuzumab is a monoclonal antibody, which is a lab-made protein that helps slow or stop the growth of cancer cells by targeting HER2 proteins. When you finish the study regimen, you will be followed by the study team for 2 years to see how you are doing.