This is an open-label, three-part study to evaluate the safety, tolerability, pharmacokinetics and immunogenicity of SHR-4602 and preliminary anti-tumor efficacy in HER2 expressing or mutated advanced malignant solid tumor subjects.

Inclusion Criteria:

1. Advanced/unresectable or metastatic solid tumor with HER2 expression or mutation that is refractory to or intolerable with standard treatment, or for which no standard treatment is available;
2. At least one measurable lesion based on RECIST v1.1 criteria;
3. ECOG PS score: 0-1 points;
4. Expected survival period ≥ 3 months;
5. Adequate organ function;
6. Must take one medically approved contraceptive measure;
7. Patients voluntarily joined the study and signed informed consent.

Exclusion Criteria:

1. Patients with known CNS metastasis or hepatic encephalopathy;
2. Suffering from peripheral neuropathy;
3. History of clinically significant lung diseases (e.g., interstitial pneumonia, pneumonitis, pulmonary fibrosis, and severe radiation pneumonitis) or suspected to have these diseases by imaging at screening period;
4. Patients with any active, known or suspected autoimmune disorder;
5. With known severe allergic reactions to any other monoclonal antibodies;
6. Patients with symptomatic ascites or pleural effusion requiring paracentesis and drainage, or patients who have undergone ascites or pleural effusion drainage within 2 weeks before the first dose;
7. Patients with other malignancies currently or within the past 5 years;
8. Uncontrolled cardiac diseases or symptoms;
9. With known hereditary or acquired bleeding (e.g., coagulopathy) or a tendency to clot (e.g., hemophiliacs);
10. Patients with other potential factors that may affect the study results.