A Study to Evaluate the Safety, Pharmacokinetics, and Antitumor Activity of AK117 as Monotherapy or in Combination With AK104

Inclusion Criteria: 1. Able to provide written and signed informed consent 2. Eastern Cooperative Oncology Group (ECOG) performance status (PS) score of 0 or 1. 3. Life expectancy ≥12 weeks 4. Females of childbearing potential and non-sterilized males who are sexually active must use an effective method of contraception from screening until 120 days after final dose of investigational product or women of non-childbearing potential. 5. Willing to receive blood transfusion(s) when so advised by the investigator. 6. Adequate organ function. 7. Subjects must have a histologically or cytologically confirmed advanced solid tumor that is refractory or relapsed to the current standard therapies or which no effective standard therapy is available. 8. At least 1 measurable lesion according to RECIST v1.1 Exclusion Criteria: 1. Concurrent enrollment in another clinical study excluding observational trials 2. Prior malignancy active within the previous 3 years except for the tumor for which a subject is enrolled in the study 3. Active brain/central nervous system (CNS) metastases 4. Active infections requiring systemic therapy within 2 weeks prior to the first dose of investigational product. 5. Known history of HIV. 6. Known active hepatitis B or C infections 7. Active or prior documented autoimmune disease that may relapse. 8. History of interstitial lung disease or non-infectious pneumonitis, except those induced by radiation therapies. 9. History of defects in RBC production, or hemoglobin production or metabolism 10. Patients with clinically significant cardio-cerebrovascular disease. 11. History of severe hypersensitivity reactions to other mAbs. 12. History of organ transplantation. 13. Receiving any anticancer therapy targeting the CD47/SIRPα ; Anticancer small molecule targeted agent within 2 weeks prior to the first dose of the investigational product; Anticancer mAbs within 6 weeks prior to the first dose of investigational product or 5 half-lives (whichever is lesser); Other anticancer therapy within 4 weeks prior to the first dose of the investigational product; 14. Subjects with a condition requiring systemic treatment with either corticosteroid (\>10 mg daily doses)) or other immunosuppressive medications within 2 weeks prior to the first dose of investigational product. 15. Received a live attenuated vaccine within 4 weeks prior to the first dose of investigational product.