A Study of MRG002 in the Treatment of Patients With HER2-expressed Advanced Malignant Solid Tumors.

Inclusion Criteria:

1. Willing to sign the informed consent form and follow the requirements specified in theprotocol.
2. Aged 18 to 75 (including 18 and 75), both genders.
3. Life expectancy ≥ 12 weeks.
4. Patients with histopathological or cytological confirmed HER2-expressed advanced solidtumors, and with at least one measurable lesion according to the Response Criteria inSolid Tumors (RECIST v1.1).
5. The score of ECOG for performance status is 0 or 1.
6. The toxicity of previous anti-tumor treatment has recovered to ≤ Grade 1 as defined byNCI-CTCAEv5.0.
7. No severe cardiac dysfunction.
8. Organ functions must meet the basic requirements.
9. Cumulative dose of anthracycline ≤ 450 mg/m2 doxorubicin or its equivalent.

Exclusion Criteria:

1. Prior treatment with chemotherapy, biological therapy, immunotherapy, radiotherapy,investigational drugs, attenuated live vaccines, immunomodulators, CYP3A4inhibitors/inducers, antibody-drug conjugates, etc.
2. Treatment with immune checkpoint inhibitors or tumor vaccines within 60 days prior tothe first dose.
3. Treatment with systemic corticosteroids or other immunosuppressive drugs within 14days prior to the first dose or during the study period.
4. History of severe cardiac disease.
5. Poorly controlled hypertension and hyperglycemia.
6. Presence of peripheral neuropathy ≥ Grade 2.
7. History of moderate or severe dyspnea at rest due to advanced malignant tumor or itscomplications or severe primary pulmonary disease, or current need of continuousoxygen therapy, or current interstitial lung disease or pneumonia.
8. Central nervous system metastasis.
9. Received major surgery within 4 weeks prior to the first dose without completerecovery.
10. History of hypersensitivity to any component of MRG002 or HX008 or known history ofhypersensitivity of ≥ Grade 3 to macromolecular protein products/monoclonalantibodies.
11. Evidence of active infection.
12. History of primary immunodeficiency or autoimmune disease.
13. Female patients with a positive serum pregnancy test or who are breast-feeding or whodo not agree to take adequate contraceptive measures during the treatment and for 6months after the last dose of study treatment.
14. Previous history of other primary malignancies.
15. Other conditions inappropriate for participation in this study, as deemed by theinvestigator.