A Phase 2 Study to Evaluate the Efficacy, Safety and Pharmacokinetics of YL202 in Patients With BC

This Phase 2 study tests YL202, a new antibody-drug conjugate that targets HER3 (a protein found on some cancer cells), in patients with advanced breast cancer — including both triple-negative and hormone receptor-positive subtypes — whose cancer has stopped responding to prior HER2 or TROP2 targeting treatments. **You may be eligible if...** - You have locally advanced or metastatic breast cancer that cannot be surgically cured - Your breast cancer is either triple-negative (HR-negative, HER2-negative) or HR-positive with HER2-low or zero expression - Your cancer has previously failed treatment with a HER2-targeting ADC or a TROP2-targeting ADC - You have at least one measurable tumor outside the brain - Your expected survival is at least 3 months - Your blood counts and organ function meet study requirements **You may NOT be eligible if...** - You have previously received a drug specifically targeting HER3 - You cannot tolerate topoisomerase I inhibitors - You have had major surgery within 4 weeks - You have had a prior bone marrow or organ transplant - You are on ongoing systemic steroids Talk to your doctor to see if this trial is right for you.