A Phase III Study of SHR-A1811 Injection With or Without Pertuzumab in HER2-Positive Recurrent or Metastatic Breast Cancer

Inclusion criteria

• Women aged 18 to 75 (inclusive)
• HER2 positive (IHC3+ or ISH+) unresectable or metastatic breast cancer confirmed by histology or cytology.
• ECOG score is 0 or 1
• An expected survival of ≥ 12 weeks
• At least one measurable lesion according to RECIST v1.1 criteria
• Have adequate renal and hepatic function
• Patients voluntarily joined the study and signed informed consent

Exclusion criteria

• Have other malignancies within the past 5 years
• Active central nervous system metastasis without surgery or radiotherapy
• In (neoadjuvant) adjuvant therapy phase, the interval from the end of systemic therapy (excluding endocrine therapy) to the detection of recurrence/metastasis ≤12 months
• Presence with uncontrollable third space effusion
• Have undergone other anti-tumor treatment within 4 weeks before the first dose
• A history of immune deficiency
• Clinically significant cardiovascular disorders
• Known or suspected interstitial lung disease
• The toxicity from previous anti-tumor treatment has not recovered to ≤ grade I
• Known hereditary or acquired bleeding tendency
• Active hepatitis and liver cirrhosis
• Presence of other serious physical or mental diseases or laboratory abnormalities