A Phase II Study of HLX22 in Combination With Trastuzumab Deruxtecan in HER2-low, Hormone Receptor Positive Locally Advanced or Metastatic Breast Cancer Patients

This Phase II study is testing a combination of two targeted therapies — HLX22 and trastuzumab deruxtecan — in patients with breast cancer that has a low level of the HER2 protein (called HER2-low) and is also hormone receptor-positive. The cancer has either spread to other parts of the body or cannot be surgically removed. **You may be eligible if...** - You are at least 18 years old - You have been diagnosed with HER2-low, hormone receptor-positive advanced or metastatic breast cancer - HER2-low means your cancer tests show low but not negative HER2 levels (specific test score required) - You have measurable tumor on imaging (not only bone metastases) - Your overall health status is good (ECOG 0–1) - Your expected survival is at least 6 months **You may NOT be eligible if...** - You have had another cancer diagnosis in the past 3 years - You have previously received certain HER2-targeted treatments - Your organ function does not meet required levels Talk to your doctor to see if this trial is right for you.