The study is being conducted to evaluate the efficacy, safety and tolerability of SHR-1701 in combination with gemcitabine and albumin paclitaxel in first-line treatment of subjects with advanced/metastatic pancreatic cancer, and determine the RP2D for SHR-1701 in the combined regimen.

Inclusion Criteria:

• Male or female subjects aged between 18 and 70 years;
• Life expectancy ≥ 12 weeks judged by the investigator.
• The ECOG performance status was 0-1.
• At least 1 measurable lesion conforming to RECIST 1.1 criteria.
• In subjects with histologically or cytologically confirmed pancreatic cancer, there was evidence of inoperable locally advanced or distant metastases.
• Adequate organ and bone marrow function.
• Female subjects of childbearing age must undergo a serum pregnancy test within 7 days before the commencement of the study and the results are negative, and are willing to use a medically approved high potency contraceptive method during the study period and within 3 months after the last administration of the study drug; For male subjects whose partner is a female of childbearing age, they should be surgically sterilized or agree to use an effective method of contraception during the study period and for 3 months after administration of the last study.
• Willing to consent and signed the informed consent, and able comply with the planned visit, research treatment, laboratory examination and other test procedures.

Exclusion Criteria:

• Known allergy to the study drug or any of its excipients; Or had a serious allergic reaction to other monoclonal antibodies.
• Previous exposure to drugs/antibodies acting on T cell co-stimulation or checkpoint pathways.
• Major surgery within 28 days before the first experimental treatment (biopsy required for diagnosis is permitted).
• Subject with central nervous system (CNS) metastases.
• Had other active malignant tumors within 5 years before entering the study. Except for basal cell or squamous cell carcinomas, superficial bladder carcinomas, carcinoma in situ of the cervix, ductal carcinoma in situ, and papillary carcinoma of the thyroid, which may be treated locally and have been cured.
• Human immunodeficiency virus (HIV) infection or known acquired immunodeficiency syndrome (AIDS), untreated active hepatitis.
• The presence of clinically significant acute or chronic pancreatitis.
• The presence of other acute or chronic infections of clinically significant significance.
• History of allogeneic organ transplantation or allogeneic hematopoietic stem cell transplantation.