This is a randomized, open label Phase II-III neoadjuvant study comparing the efficacy and safety of ARX788 combined with pyrotinib maleate versus TCBHP (trastuzumab plus pertuzumab with docetaxel and carboplatin) in patients with HER2-positive breast cancer. Patients will be randomized (1:1) to one of the two treatment arms: arm 1, ARX788 plus pyrotinib maleate for 6 cycles; arm 2, trastuzumab plus pertuzumab with docetaxel and carboplatin for six cycles. Patients will undergo surgery after neoadjuvant therapy. Efficacy will be assessed every 2 cycles.