This is a randomized, open, positive drug control, multi center phase III study. Through the evaluation of tpCR, bpCR, ORR, EFS, IDFS, OS , AEs and other indicators, it proves the effectiveness and safety of TQB2102 for injection versus TCbHP in the neoadjuvant treatment of HER2 positive breast cancer patients.

Inclusion Criteria:

• Voluntarily participate in this study, sign the informed consent form, and have good compliance;
• Eastern Cooperative Oncology Group performance status (ECOG PS) score: 0-1; expected survival >6 months;
• Histologically or cytologically confirmed HER2-positive invasive breast cancer;
• Hormone receptor (HR) status confirmed;
• Clinical stage at diagnosis: T2-4 with any N, M0, or any T with N1-3, M0;
• Agree to undergo breast cancer resection if meeting surgical criteria after neoadjuvant therapy;
• Major organ function is adequate, meeting specific criteria;
• Must agree to use contraception during the study and for 6 months after study completion; female patients must have a negative serum pregnancy test within 7 days before enrollment and must not be lactating; male subjects must agree to use contraception during the study and for 6 months after study completion

Exclusion Criteria:

• Stage IV metastatic breast cancer or other cases judged by the investigator as unsuitable for radical surgical resection after neoadjuvant therapy;

• Bilateral breast cancer or inflammatory breast cancer;

• History of invasive breast cancer or ductal carcinoma in situ;

• Prior anti-tumor therapy for breast cancer, including chemotherapy, endocrine therapy, targeted therapy, radiotherapy, surgery, etc.;

• Comorbidities and medical history:

  • Other malignancies within 5 years or currently;
  • Adverse reactions from prior treatment not recovered to CTCAE v5.0 grade ≤1;
  • Major surgery, significant traumatic injury within 4 weeks before first dose, or anticipated major surgery during the study, or unhealed wounds/fractures;
  • Conditions affecting intravenous injection or blood sampling;
  • Congenital bleeding or coagulation disorders, or bleeding/coagulation disorders within 28 days before study treatment, or use of aspirin >325 mg/day (maximum antiplatelet dose), dipyridamole, ticlopidine, clopidogrel, or cilostazol within 7 days before study treatment;
  • Arterial/deep venous thrombotic events within 6 months before first dose, e.g., cerebrovascular accident, deep vein thrombosis, pulmonary embolism;
  • Poorly controlled blood pressure (systolic ≥150 mmHg or diastolic ≥100 mmHg);
  • Significant cardiovascular disease, including；
  • Uncontrolled ≥CTCAE grade 2 infection within 14 days before study treatment;
  • History of interstitial lung disease/pneumonitis (non-infectious) requiring steroid treatment, current interstitial lung disease/pneumonitis, or suspected interstitial lung disease/pneumonitis on screening imaging that cannot be ruled out;

• Tumor-related symptoms and treatment:

  • Prior excisional biopsy of primary tumor and/or axillary lymph nodes or sentinel lymph node biopsy before study treatment;
  • Surgery, chemotherapy, radiotherapy, or other anti-tumor therapy within 3 weeks before study treatment (washout period calculated from last treatment);
  • Prior taxane or carboplatin therapy for any malignancy;
  • Treatment with National Medical Products Administration-approved traditional Chinese medicine with clear anti-tumor indications within 2 weeks before study treatment.

• Study treatment-related:

  • Severe hypersensitivity to monoclonal antibodies;
  • Uncontrolled active autoimmune disease within 2 weeks before study treatment;
  • Allergy to any study drug or its components/excipients;
  • Live vaccination within 28 days before study treatment, including measles, mumps, rubella, varicella, yellow fever, seasonal flu, Influenza A virus subtype (H1N1) flu, rabies, Bacille Calmette-Guerin vaccine (BCG), and typhoid vaccines.

• Any condition judged by the investigator to jeopardize subject safety or study completion.