A Study of A166 in Patients With HER2-Positive Unresectable or Metastatic Breast Cancer

Exclusion Criteria

• •1. Previous treatment with A166 or any HER2-targeted antibody-drug conjugate (ADC) with a microtubule inhibitor payload.
• •2. Known history of severe hypersensitivity to other monoclonal antibodies, or allergy to A166 or their components.
• •3. Permanent discontinuation of trastuzumab or its biosimilars due to any toxicity in prior treatments.
• •4. Presence of severe corneal epithelial disease at baseline; or inability to perform daily activities without contact lenses.
• •5. Presence of spinal cord compression or clinically active central nervous system (CNS) metastases.
• •6. Other conditions considered by the investigator to make the patient unsuitable for participation in the study.