To evaluate the efficacy and safety of toripalimab in combination with investigator-selected chemotherapy in patients with recurrent or metastatic HER2-negative breast cancer who have failed prior systemic therapy.
Voluntary participation: the subject must give written informed consent, be compliant, and agree to attend all follow-up visits.
Age ≥ 18 years.
ECOG performance-status score ≤ 1 and life expectancy ≥ 3 months.
Histologically or cytologically confirmed HER2-negative breast cancer (HER2-negative is defined as either IHC 0, IHC 1+, or IHC 2+ with a negative in-situ-hybridisation [ISH] result).
Uncontrolled central-nervous-system metastases (symptomatic or requiring corticosteroids or mannitol for symptom control).
Clinically significant or uncontrolled cardiac disease within 6 months before first dose, including congestive heart failure, angina, myocardial infarction, or ventricular arrhythmia.
Malignancy within 5 years before first dose, except adequately treated basal-cell carcinoma of the skin or carcinoma in situ of the cervix.
Active autoimmune disease requiring systemic therapy within 2 years before first dose, except vitiligo, type-1 diabetes, or residual hypothyroidism due to autoimmune thyroiditis managed with hormone replacement only.