RC48 Plus Bevacizumab or Pyrotinib in HER2-Positive Metastatic Breast Cancer After T-DXd Failure: A Phase II Study

This phase II study tests two treatment combinations — RC48 (an antibody-drug that targets HER2) plus either bevacizumab (a blood vessel blocker) or pyrotinib (a targeted HER2 blocker) — in people with HER2-positive metastatic breast cancer whose cancer stopped responding to T-DXd (trastuzumab deruxtecan), a standard HER2-targeted therapy. **You may be eligible if...** - You are 18 years or older - You have HER2-positive breast cancer that has spread (confirmed by tissue testing: IHC 3+ or IHC 2+ with gene amplification) - Your cancer progressed during or after treatment with T-DXd (trastuzumab deruxtecan) - You have at least one measurable tumor on imaging - You are in good overall health (ECOG performance status 0 or 1) - Your blood counts and organ function are adequate **You may NOT be eligible if...** - Your cancer has not yet been treated with T-DXd or did not progress on it - Your HER2 status is negative or low - Your overall health or organ function is significantly impaired Talk to your doctor to see if this trial is right for you.