Study of SHR-A1811 in HER2-expression Advanced Breast Cancer With Brain Metastases

This study is testing SHR-A1811, an antibody-drug conjugate that delivers chemotherapy directly to HER2-positive or HER2-low breast cancer cells, in women with advanced breast cancer that has spread to the brain and has not yet received local treatment (such as radiation) for those brain tumors. **You may be eligible if...** - You are a woman aged 18 or older - You have confirmed HER2-positive or HER2-low advanced breast cancer - You have at least one measurable brain tumor that has not yet been treated locally - You have not received prior brain radiation - At least 2 weeks have passed since your last systemic treatment **You may NOT be eligible if...** - You have already received radiation to the brain - There is an immediate need for local brain treatment (e.g., surgery or radiation) - You have HER2-low disease and have already received systemic treatment for brain metastases Talk to your doctor to see if this trial is right for you.