A Study to Evaluate the Safety, Tolerability, Pharmacokinetics (PK), and Antitumor Activity of ALK201 in Participants With Advanced Solid Tumors

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 * Eastern Cooperative Oncology Group Performance Status (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 from the date of signing the ICF until at least 6 months after the last dose of the IP, and during this period, male participants are not allowed to donate sperms Exclusion Criteria: * Active or pre-existing autoimmune diseases that may relapse * Pleural effusion, pericardial effusion, or intraperitoneal effusion accompanied with clinical symptoms, clinically poorly controlled, or requiring repeated drainage * Allergies to any component of ALK201 or other monoclonal antibodies * Primary central nervous system malignancies, or active metastases to central nervous system and/or metastases to meninges * Combined with ≥ Grade 2 stomatitis and/or nose bleeding at screening * Vaccinated with live vaccines within 4 weeks prior to the first dose Note: Other protocol defined Inclusion/Exclusion criteria may apply