A Study of MR001 in Patients With Locally Recurrent or Metastatic Advanced Triple-Negative Breast Cancer (TNBC)

Inclusion Criteria:

• Patients with histologically or cytologically confirmed triple-negative breastcancer (TNBC).

• Subjects with locally recurrent or metastatic advanced TNBC who have progressedafter first-line or later-line therapy.

• Presence of at least one measurable lesion according to RECIST V1.1 criteria.

• ECOG Performance Status 0 or 1.

• Life expectancy >3 months.

• Adequate organ and hematopoietic function based on the laboratory tests.

• Voluntarily sign the informed consent form.

Exclusion Criteria:

• History of severe allergy or hypersensitivity to the investigational product or itsexcipients or drugs of similar chemical class (e.g., monoclonal antibodies), orcontraindications to the investigational product.

• Requirement for systemic immunosuppressive therapy within 14 days prior to the firstdose of study drug or during the study.

• Major surgery (excluding puncture biopsy) within 4 weeks prior to the first dose ofstudy drug, or anticipated need for major surgery during this study.

• Uncontrolled active brain metastases or leptomeningeal metastasis.

• History of autoimmune disease requiring treatment with corticosteroids orimmunosuppressive drugs.

• Women in the period of preconception, pregnancy, or lactation.

• Any other circumstances which the investigator considers may increase risks tosubjects or interfere with the results of the trial.