A Study Comparing MRG004A Plus Best Supportive Care Versus Placebo and Best Supportive Care in the Treatment of Patients With Advanced Pancreatic Cancer

Inclusion Criteria:

* Willing to sign the informed consent form and follow the requirements specified in the protocol.
* Patients with histologically and cytologically confirmed locally advanced or metastatic pancreatic cancer, including adenocarcinoma, who have failed at least prior systemic therapies including gemcitabine and fluorouracil.
* Patients must have at least one measurable lesion according to the Response Evaluation Criteria in Solid Tumors (RECIST v1.1).
* The score of ECOG for performance status is 0 to 2.
* Organ functions and coagulation function must meet the basic requirements.
* Patients with childbearing potential must use effective contraception during the treatment and for 6 months after the last dose of treatment.

Exclusion Criteria:

* History of other primary malignant tumors
* Active metastasis to brain or meninges
* Active acute or chronic inflammatory skin disease, history of Steven-Johnson syndromes
* History of active or chronic corneal and conjunctival diseases, or other clinically significant ocular diseases that affect the ophthalmic monitoring of the investigational drug
* Received certain anti-tumor therapies or strong CYP3A4 inhibitors and have not complete the wash-out period, or have not fully recovered from major surgery
* AEs due to prior anti-tumor therapy(ies) that have not resolved to ≤Grade 1 per CTCAE v5.0
* Presence of ≥Grade 2 peripheral neuropathy per CTCAE v5.0
* Poorly controlled pleural and peritoneal effusion or pericardial effusion
* Severe cardiac dysfunction within 6 months before enrollment
* History of ventricular tachycardia, or torsade des pointes
* Uncontrolled or poorly controlled hypertension
* Compression fractures of the spine that have not been treated with surgery and/or radiation therapy, or have not been stable within 2 weeks before randomization
* Pulmonary embolism or deep vein thrombosis within 3 months prior to the first dose of study drug.
* Patients with high risk of bleeding per investigator's judgement.
* Patients who have active infection including but not limited to hepatitis B, hepatitis C, AIDS, or syphilis.
* Active uncontrolled bacterial, viral, fungal, rickettsial, or parasitic infection.
* Moderate to severe dyspnea at rest, severe primary lung disease, interstitial lung disease, or pneumonia.
* Uncontrolled pain due to cancer
* Active or history of autoimmune disease that requiring systemic hormone therapy
* History of hypersensitivity to any component of the investigational product.
* Other situations that are not suitable to participate a clinical trial per investigator's judgement