A Multicenter, Open-label, Single-arm, Phase II Study of Mitoxantrone Hydrochloride Liposome Injection in Patients With Advanced HER2 Negative Breast Cancer

• Voluntarily participate in this study and sign informed consent form;

• Male or female patients aged 18 to 75 years (inclusive);

• Histologically confirmed diagnosis of HER-2 negative breast cancer (Including immunohistochemistry HER2 0 or 1+, immunohistochemistry HER2 2+ must be confirmed as negative by in situ hybridization);

• Patients with unresectable locally advanced or recurrent breast cancer with disease progression after first-line or higher chemotherapy；

• Hormone receptor (HR) negative breast cancer or HR-positive breast cancer that is not suitable for endocrine treatment or is resistant to endocrine treatment.

• Prior treatment with both an anthracycline (i.e., doxorubicin or epirubicin) and a taxane (i.e., paclitaxel or docetaxel) at least (acceptable for patients not previously treated with anthracyclines due to high risk factors for cardiotoxicity), and four prior chemotherapy regimens at most；

• At least one measurable lesion according to RECIST v1.1;

• Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2;

• Patients must meet the following criteria prior to treatment (not receiving blood transfusion or growth factors therapy within 14 days before the first administration):

‣ Absolute neutrophil count (ANC) ≥ 1.5 × 109/L;

⁃ Hemoglobin ≥ 90g / L;

⁃ Platelet count ≥ 90 × 109/L;

⁃ Creatinine ≤1.5 × upper limit of normal (ULN);

⁃ Total bilirubin ≤ 1.5×ULN;

⁃ Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 3 ×ULN (≤ 5 ×ULN for liver metastasis);

⁃ For women of childbearing potential: the serum pregnancy test must be negative, and patients are willing to take adequate contraceptive measures during the treatment period and for at least 6 months after the last dose of the study drug;

⁃ Good compliance and willingness to cooperate with follow-up visits.