2. Has an Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0 or 1;
3. Has an anticipated life expectancy of ≥ 12 weeks;
4. Adequate bone marrow and organ function:
5. At least 1 evaluable lesion according to Response Evaluation Criteria in Solid Tumors (RECIST) Version 1.1. for dose escalation , and 1 measurable lesion for dose expansion.
6. Has a documented (histologically- or cytologically-proven), unresectable, locally advanced or metastatic solid tumor that is refractory to or intolerable with standard treatment, or for which no standard treatment is available; participants who refuse standard therapy, or are able to suspend standard therapy without major risks.
You may not be if
1. Progressed or refractory to an ADC that consists of an Exatecan derivative that is a topoisomerase I inhibitor or intolerable with an ADC that consists of Exatecan;
2. Plan to receive other antitumor therapy during the study excluding palliative radiotherapy for the purpose of symptom (like pain) relief that must also not have an impact on tumor assessment throughout the study;
3. Pyloric obstruction and/or persistent recurrent vomiting (≥ 3 times in 24 hours);
4. Gastrointestinal perforation and/or fistula within 6 months prior to first administration of the study drug, and not recovered after surgical treatment;
5. Known symptomatic central nervous system (CNS) metastases.
6. History of pneumonia requiring corticosteroids therapy, or history of clinically significant lung diseases; Uncontrolled diseases;
7. History of endotracheal or gastrointestinal stent implantation;
8. Ascites, pleural effusion, or pericardial effusion with symptoms and requiring intervention;
9. Esophageal or gastric varices requiring immediate intervention;
11. Do not have adequate treatment washout period before study drug administration. -