Anlotinib With Trastuzumab Deruxtecan for Previously Treated HER2-Low Advanced Breast Cancer

Inclusion Criteria

• •1\. Age 18 - 75 years; ECOG PS 0 or 1. 2. Pathologically documented breast cancer that:
• •1. Is unresectable or metastatic.
• •2. Has a history of low HER2 expression (IHC 1+\& IHC 2+/ISH- or 0\<IHC\<1+).
• •3. Is HR-positive or HR-negative.
• •4. Has progressed on, and would no longer benefit from, endocrine therapy.
• •5. Has been treated with ≥1 prior lines of chemotherapy/adjuvant in the recurrent or metastatic setting.
• •3\. At least 1 measurable lesion per Response Evaluation Criteria in Solid Tumors version 1.1（Previously treated lesions with radiotherapy or focal therapy and no progression cannot be included as target lesion for assessment）.
• •4\. Has protocol-defined adequate bone marrow, renal, hepatic and blood clotting functions.
• •5\. Male and female subjects of reproductive/childbearing potential must agree to use a highly effective form of contraception or avoid intercourse during and upon completion of the study and after the last dose for at least 6 months.