TThis is a first-in-human (FIH), open-label, multicenter dose escalation and expansion study of ALK202. The purpose of this study is to evaluate the safety, tolerability, pharmacokinetics (PK), and antitumor activity of ALK202 as a monotherapy in adult participants with Advanced Solid Tumors. The study will also identify recommended dose(s) for subsequent clinical studies of ALK202.

Inclusion Criteria:

• Men and women ≥18 and ≤75 years old on the day of signing the ICF
• At least 1 measurable lesion per RECIST v1.1
• Expected survival ≥3 months
• ECOG PS score of 0 or 1
• Adequate organ function
• Female participants of childbearing potential or male participants whose partner is a female of childbearing potential agree to use medically effective contraceptive methods (abstinence, birth control pills, barrier contraception, intra-uterine contraceptive device, etc.) from the date of signing the ICF until at least 6 months after the last dose of ALK202, and during this period, male participants are not allowed to donate sperms.

Exclusion Criteria:

• Received organ transplant or hematopoietic stem cell transplant previously
• Vaccinated with live vaccines within 4 weeks prior to the first dose
• Primary central nervous system malignancies, or active metastases to central nervous system and/or metastases to meninges
• Pregnant or lactating women
• Pleural effusion, pericardial effusion, or intraperitoneal effusion accompanied with clinical symptoms, clinically poorly controlled, or requiring repeated drainage.
• Evidence of other severe or uncontrolled systemic diseases (e.g., decompensated respiratory disorder, hepatic disease, or renal disease).

Note: Other protocol defined Inclusion/Exclusion criteria may apply.