KN026 in Patients With HER2 Expressing Breast Cancer and Gastric Cancer

Inclusion Criteria:

Male or female subject >= 18 years
Histologically/cytologically confirmed, locally advanced unresectable or metastatic breast cancer or gastric cancer.
ECOG score 0 or 1
Life expectancy >3 months
According to the definition of RECIST1.1, the patient has at least one measurable lesion
Adequate organ function prior to start treatment with KN026
Able to understand, voluntarily participate and willing to sign the ICF
Subjects (women of child-bearing potential and males with fertile female partner) must be willing to use viable contraception method.

Exclusion Criteria:

Accepted any other anti-tumor drug therapies within 4 weeks before fist dose
Accepted radiotherapy within 4 weeks before enrollment
An anthracyclines antibiotic treatment was received exceeding 300 mg/m² within 90 days before first KN026 dosing, or other equivalent dose antharcyclines
Subjects are eligible with clinically controlled and stable neurologic function >= 4 weeks, which is no evidence of CNS disease progression; Subjects with spinal cord compression and cancerous meningitis are not eligible
Pregnant or nursing femalesï¼›or intend pregnancy within this study period or within 6 monthes after the end of this study
History of immunodeficiency, including HIV positive or other acquired, congenital immunodeficiency disease, or a history of organ transplantation
Severe chronic and active infection, need to system antibiosis/antiviral treatment
Cavity effusion (pleural effusion, ascites, pericardial effusion, etc.) are not well controlled, and need locally treatment or repeated drainage