• Voluntarily sign the informed consent and follow the requirements of the protocol.

• Age: ≥18 years old and ≤75 years old.

• Expected survival time ≥3 months.

• ECOG 0 or 1.

• Pathologically and/or cytologically confirmed patients who have failed standard treatment, or have no access to standard treatment Patients with unresectable, locally advanced or recurrent, metastatic HER2-negative breast cancer after posterior line.

• Agree to provide archived tumor tissue specimens (unstained sections (anti-slip)) from primary or metastatic sites within 2 years. 10 to 12 surgical specimens (4-5 μm thick) or fresh tissue samples if the subject is unable to provide them for 2 years tumor tissue samples from within, can be communicated with the sponsor if other inclusion criteria are met, enrollment was permitted after investigator assessment.

• Must have at least one measurable lesion according to RECIST v1.1 definition; So let's say that we've done this before radiotherapy-treated lesions were included only if there was definite disease progression in the lesion after radiotherapy measurable lesions were entered.

• Blood transfusions, the use of any cell growth factors, and/or blood transfusions were not allowed within 14 days before screening in the presence of a platelet drug, the organ function level must meet the following criteria:

∙ Blood routine: hemoglobin (HGB) ≥ 90g/L; Absolute neutrophil count (NEUT) ≥ 1.5× 10 9 /L; Platelet count (PLT) ≥ 90× 10 9 /L;

‣ Renal function: creatinine (Cr) ≤1.5 ULN, or creatinine clearance (Ccr) ≥50 mL/min (According to Cockcroft and Gault formula);

‣ Liver function: total bilirubin (TBIL≤1.5 ULN), alanine aminotransferase (ALT) and Aspartate aminotransferase (AST) was ≤2.5 ULN in all patients, and AST and ALT were ≤ in patients with liver metastasis 5.0 ULN;

‣ Coagulation function: international normalized ratio (INR) ≤1.5 and activated partial thromboplastin time (APTT) ≤1.5ULN;

‣ no severe cardiac dysfunction with left ventricular ejection fraction ≥50%;

‣ proteinuria ≤2+ or ≤1000mg/24h.

• Toxicity from previous antineoplastic therapy has returned to grade 1 or less as defined by NCI-CTCAE v5.0 (investigator review) concerns about asymptomatic laboratory abnormalities such as elevated ALP, hyperuricemia, hyperglycemia, etc., and investigators toxicity without safety risk was judged, such as alopecia, grade 2 peripheral neurotoxicity, or decreased hemoglobin but ≥90g/L except).

⁃ A pregnancy test should be performed within 7 days of starting treatment for premenopausal women who are likely to have children clear or urine pregnancy tests must be negative and must be non-lactating; All enrolled patients should be in the entire treatment week adequate barrier contraceptive measures were taken at the end of treatment and 6 months after the end of treatment.