Phase Ⅰ Study to Evaluate the Safety and Tolerability of Using F520

Inclusion Criteria:

1. Male or female 18-65 years of age;
2. Histologically or cell confirmed advanced, unresectable or metastatic disease tumor and failure to standard therapies or lack of standard therapy(disease progress or failed to tolerate the toxicity, such as chemotherapy, targeted therapy, and other immunotherapies other than PD-1/PD-L1);
3. Agree to provide archived tumor tissue specimens or fresh tissue specimens;
4. ECOG performance status of 0 or 1;
5. Life expectancy ≥ 12 weeks.;
6. At least one measurable and evaluable tumor lesion (in accordance with international working group criteria/RANO/cheson 2007)；
7. Adequate laboratory parameters during the screening period as evidenced by the following（No blood components and cell growth factors are allowed within 28 days prior to screening）:

   routine blood tests: Absolute neutrophil count ≥1.0×109/L ;Platelets ≥100×109/L;Hemoglobin ≥ 9.0 g/dL; Liver function：Total bilirubin (TBIL) ≤1.5×upper limit of normal (ULN), ALT and AST ≤2.5ULN; for subjects with liver metastases, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤ 5×ULN, Total bilirubin (TBIL) ≤3×upper limit of normal (ULN); Renal function CCr≤1.5×ULN，Creatinine clearance≥50 mL/min;
8. Thyroid function indicators: thyroid-stimulating hormone (TSH) and free thyroxine (FT3/FT4) are within the normal range;
9. Understand study procedures and contents, and voluntarily sign the written informed consent form.

Exclusion Criteria:

1. Subjects with any active autoimmune disease or history of autoimmune disease, including but not limited to the following: Immune-related neurological diseases, multiple sclerosis, autoimmune (demyelinating) neuropathy, Guillain-Barre syndrome, myasthenia gravis, systemic lupus erythematosus, connective tissue disease, scleroderma, inflammatory bowel disease including Crowe Enthusiasm and ulcerative colitis, autoimmune hepatitis, toxic epidermal necrolysis or Stevens-Johnson syndrome；
2. Presence of symptomatic central nervous system (CNS) metastases；
3. Concurrent medical condition requiring the use of immunosuppressive medications, or immunosuppressive doses of systemic or absorbable topical corticosteroids. Doses \> 10 mg/day prednisone or equivalent are prohibited within 14 days before entering the group and during the study period;
4. Prior radiotherapy, systemic chemotherapy hormone therapy, surgery or target therapy within 4 weeks or 5 half-lives(whichever is longer) before the study drug administration, or any unresolved AEs \> CTC-AE Grade 1;
5. Autologous hematopoietic stem cell transplantation (ASCT) has been completed at least 3 months before receiveing first dose;
6. Known history of hypersensitivity to macromolecular protein preparation or any components of the F520 formulation；
7. Patients receiving any anti-infection vaccine within 4 weeks before enrollment;
8. History or concurrent with other malignant disease, except completely cured basal cell skin cancers and carcinoma in situs of cervix;
9. Uncontrolled clinically significant heart disease, including but not limited to the following: (1) \>2 NYHA 2 congestive heart failure; (2) unstable angina, (3) myocardial infarction within the past 1 year; (4) clinically significant supraventricular arrhythmia or ventricular arrhythmia requirement for treatment or intervention;
10. Active infection（needing therapy） or an unexplained fever \> 38.5°C during screening or before the first scheduled day of dosing (subjects with tumor fever may be enrolled at the discretion of the investigator);
11. Patients with active pulmonary tuberculosis; patients who previously had active pulmonary tuberculosis;
12. History of immunodeficiency (HIV) or active hepatitis(Hepatitis B: HBsAg, Anti-HBs, HBeAg, Anti-HBe, Anti-HBc,HBV-DNA; Hepatitis C: Anti-HCV,HCV-RNA)
13. Participation in a clinical study or less than 1 month from the last dose of investigational drug to sign ICF;
14. History of PD-1/PD-L1 or CTLA-4 therapy;
15. Patients with drug abuse history or alcohol addiction history;
16. Patients with current or previous interstitial lung diseases;
17. Female and male who have reproductive potential must be willing and able to employ a highly effective method of birth control/contraception to prevent pregnancy while on treatment and for at least 6 months after receiving the last dose of study treatment.
18. Other factors that may lead to the termination of the participation in the study at the discretion of the investigators.