A First-in-Human Study of SON-DP in Participants With Relapsed/Refractory Intolerant to Standard of Care Therapies for Advanced/Metastatic Solid Tumors

Inclusion Criteria:

1. Signed written informed consent;
2. Male or female participants aged ≥ 18 years;
3. For Phase Ia: Participants with histologic diagnosis and confirmed solid tumor; For Phase Ib: Participants with one of the four tumor types: breast cancer, pancreatic cancer, ovarian cancer or colorectal cancer;
4. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 at study entry and an estimated life expectancy of at least 3 months;
5. Agree to the placement of drug infusion venous access;
6. For high dose group, agree for two biopsies, one at screening and one at 1st week of cycle 3;
7. Adequate hematological function;
8. Adequate hepatic/renal function;
9. Acceptable coagulation function;
10. Recovered from prior treatment Adverse Effect;
11. Effective contraception for female participant with child bearing potential participants and sexually active male participants.

Exclusion Criteria:

1. Participation in investigational study within 2 weeks or 5 half-lives, whichever is shorter of the first dose of study treatment.
2. Impaired cardiac function or clinically significant cardiac disease.
3. History of stroke or clinically significant intracranial hemorrhage within 6 months before first dose of study drug.
4. Malignant disease, other than that being treated in this study.
5. Anticancer therapy within 5 half-lives or 2 weeks (whichever is shorter) prior to study entry.
6. Active infection requiring intravenous systemic antibiotic or antiviral therapy within 14 days prior to the first dose of study drug.
7. Major surgery within 4 weeks of the first dose of study treatment.
8. Any medical condition that would, in the Investigator's judgment, prevent the participant's participation in the clinical study due to safety concerns, compliance with clinical study procedures, or interpretation of study results.
9. Active pneumonitis, the suspected pneumonitis that cannot be ruled out based on the imaging at Screening or based on the Investigator's judgement and a history of the (non-infectious) pneumonitis that required steroids within the past 12 months