The purpose of this study is to determine whether SCT200 is safe and tolerant in the treatment of metastatic colorectal cancer

Inclusion Criteria:

• aged from 18 to 70 years;

• having histologically confirmed metastatic colorectal cancer;

• having experienced previous treatment failures including fluoropyrimidine, irinotecan and oxaliplatine chemotherapy regiment;

• having determined wild-type KRAS tumor;

• having to have measurable or nonmeasurable disease per Response Evaluation Criteria In Solid Tumors (RECIST) version 1.1;

• Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1; and expected survival of at least ≥3 months;

• adequate hematological, renal and liver functions:

  1. Hematological function: white blood cell count of >4.0×109/L; absolute neutrophil count of >1.5×109/ L; platelet count of >100×109/L; hemoglobin level of >90.0 g/L;
  2. Renal function: serum creatinine level of<1.5×upper limit of normal (ULN);
  3. Liver function: total bilirubin level of<1.5×ULN; aspartate amino transferase (AST) and alanine amino transferase (ALT) levels of <1.5×ULN; or <5 × ULN for patients with liver metastases;

• no other malignancies only if they had following malignancies , which were not required to treat or who had curative resection: cervical carcinoma in situ, the skin basal carcinoma or squamous cell carcinoma, bladder epithelial tumors, or only they had some malignancies requirement only surgical therapy and disease free survival≥5 years;

• no serious nonmalignant diseases including hypertension, diabetes mellitus, coronary artery disease, and mental disorder.

• not pregnant; or not lactating; or accepted birth control methods during the study;

• signed an informed consent form which was approved by the institutional review board of the respective medical center .

Exclusion Criteria:

• had received EGFR target treatment including EGFR tyrosine kinase inhibitors(TKI), or anti- EGFR monoclonal antibody;
• having to be at least 4 weeks beyond prior anticancer therapy (including corticosteroid , or nitrosourea or mitomycin within 6 weeks of study entry) or participating in other clinical trial, or have not recovered from significant toxicities of prior therapy;
• chronic use of medication that could interfere with the assessment of drug-related toxicities or immunologic activity (high dose prednisone or high dose non-steroid anti-inflammatory medication);
• had recent major surgery (within 28 days);
• with symptomatically brain metastases (with the exception of clinically brain metastases stable and of no requirement further treatment);
• with active infection requirement systemic antibiotics treatment; or serious cardiovascular disease;or with evidence of active hepatitis B or C infection; or with human immunodeficiency virus infection;
• had acute pulmonary disorder; or interstitial pneumonia; or symptomatically chronic obstructive pulmonary disease (COPD) or with risk factors to COPD;
• with eye inflammation or infection, or any risk factors who could lead to eye disease;
• with a history of allergic reaction or protein product allergy including antibodies product;
• pregnant, or lactating, or not accepted birth control methods including male patients.
• had a history of alcohol or drugs addiction, or with any risk which may affect the patient's health evaluation or mantle state