Study of SHR2150 (TLR7 Agonist) in Combination With Chemotherapy Plus PD-1 or CD47 Antibody in Subjects With Unresectable/ Metastatic Solid Tumors

Inclusion Criteria: 1. Subjects must have histologically proven unresectable/ metastatic solid tumors. 2. ≥ 18 years old. 3. Life expectancy of at least 6 months. 4. Eastern Cooperative Oncology Group performance status 0-3. 5. Subjects must have at least one measurable lesion ≥ 1 cm as defined by response criteria. 6. Subjects must have received at least two frontlines therapies, except for patients initially diagnosed with local advanced or metastatic pancreatic cancer or cholangiocarcinoma. 7. Subjects must be off prior therapy for at least 4 weeks prior to Day 1. Subjects with autologous hematopoietic stem-cell transplantation are eligible which must be more than 3 months. Subjects with Anti-PD-1 antibody are eligible which must be resistance. 8. Adequate organ function. 9. Female participants of childbearing potential must be willing to use an adequate method of contraception for the course of the study through 120 days after the last dose of study drug. 10. Male participants of childbearing potential must agree to use an adequate method of contraception, starting with the first dose of study drug through 120 days after the last dose of study drug. Exclusion Criteria: 1. Subjects with any autoimmune disease or history of syndrome that requires corticosteroids or immunosuppressive medications. 2. Serious uncontrolled medical disorders or active infections, pulmonary infection especially. 3. Prior organ allograft. 4. Women who are pregnant or breastfeeding. 5. Women with a positive pregnancy test on enrollment or prior to investigational product administration. 6. Subjects who are compulsorily detained for treatment of either a psychiatric or physical (eg, infectious disease) illness.