Disitamab Vedotin + Pyrotinib Versus THP in the First-line Treatment for HER2+ Advanced Breast Cancer Clinical Trial

The goal of this multicentre, randomized, double-blind controlled, phase III clinical trial is to compare the efficacy and safety of disitamab vedotin in combination with pyrotinib versus the standard first-line treatment of paclitaxel in combination with trastuzumab and pertuzumab (THP) for newly diagnosed recurrent/metastatic Human epidermal growth factor receptor 2 (HER2) positive advanced breast cancer, and to explore the impact of biomarkers on clinical efficacy and safety. The main questions it aims to answer are: * Analyse the efficacy and safety of disitamab vedotin in combination with pyrotinib versus the standard first-line treatment of THP. * Explore the impact of biomarkers on clinical efficacy and safety of the combination of disitamab vedotin in combination with pyrotinib treatment. Participants in the experimental group will receive disitamab vedotin in combination with pyrotinib for 6-8 cycles (each cycle lasting 28 days), followed by maintenance treatment with trastuzumab in combination with pyrotinib. Participants in the control group will receive paclitaxel in combination with trastuzumab and pertuzumab for 6-8 cycles (each cycle lasting 21 days), followed by maintenance treatment with trastuzumab and pertuzumab. Researchers will compare disitamab vedotin in combination with pyrotinib versus the standard first-line treatment of paclitaxel in combination with trastuzumab and pertuzumab to see if disitamab vedotin in combination with pyrotinib could be a new option for first-line treatment of HER2-positive metastatic breast cancer.