M108 is a monoclonal antibody specific for gastric and gastroesophageal adenocarcinomas. The aim of this phase I study is to establish safety and Tolerability of different Dosage regimen in patients With Advanced Unresectable Solid Tumors in China.

Inclusion Criteria:

1. Written informed consent.
2. Advanced Unresectable solid tumors proven by histology
3. At least 1 measurable site of the disease according RECIST 1.1 criteria
4. ECOG performance status (PS) 0-1
5. Life expectancy > 3 months
6. Age ≥ 18 years and ≤75 years
7. Adequate haematological function; absolute neutrophil count ≥1.5 x 109/L; white blood cell count ≥3.0 x 109/L; platelets ≥100 x 109/L; haemoglobin ≥9 g/dL.
8. Adequate coagulation function; international normalized ratio ( INR) ≤ 1.5 x upper limit of normal (ULN), or activated partial thromboplastin time (APTT) ≤ 1.5 x ULN.
9. Adequate hepatic function; bilirubin ≤1.5 x ULN, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) ≤2.5 x ULN.
10. Adequate renal function; creatinine ≤1.5 x ULN, or reatinine clearance rate ≥60 mL/minute calculated.

Exclusion Criteria:

1. Previous received or planned to be vaccinated with 2019-nCoV vaccine or other vaccines within 3 months prior to the start of study treatment or during the study or within 3 months after the end of the study;
2. Previous radiotherapy within 4 weeks prior to the start of study treatment. (if palliative radiotherapy was given to bone metastatic side peripherally and the patient recovered from acute toxicity was allowed).
3. Previous anti-tumor therapy within 4 weeks prior to the start of study treatment.
4. Previous major operation within 8 weeks prior to the start of study treatment.
5. Prior severe allergic reaction or intolerance to a monoclonal antibody, including humanised or chimeric antibodies.
6. Symptomatic cerebral metastases.
7. Uncontrolled or severe illness.
8. Known human immunodeficiency virus infection or known symptomatic hepatitis
9. Other clinically significant disease which may have adversely affected the safe delivery of treatment within this study