A Phase I Study of GC33 in Advanced or Metastatic Liver Cancer (Hepatocellular Carcinoma)

Inclusion Criteria: * Signed written Institutional Review Board (IRB)/Ethical Committee (EC) approved informed consent form * Male or female ≥ 18 years old. * Life expectancy ≥ 3 months. * ECOG Performance Status of 0-1. * Histologically confirmed hepatocellular carcinoma (without fibrolamellar subtype). * Not a candidate for curative treatments. * Child-Pugh A or B. * Hematological, Biochemical and Organ Function: * AST (SGOT): ≤ 5.0 × ULN * ALT (SGPT): ≤ 5.0 × ULN * Total Bilirubin: ≤ 3.0 × ULN * Platelets: ≥ 50,000/μL * Absolute Neutrophil Count: ≥ 1,500/μL * Serum creatinine: ≤ 2.0 × ULN * PT-INR: ≤ 2.0, * Ability to provide a tumor tissue sample either by: * a sample obtained within 3 months prior to informed consent for HCC diagnosis. Resection samples are not acceptable. * undergo a biopsy to confirm HCC diagnosis * At least one measurable lesion based on Response Evaluation Criteria In Solid Tumors criteria. (Extension Phase) * Signed written Institutional Review Board (IRB)/Ethical Committee (EC) approved informed consent form. * Male or female ≥ 18 years old. * Life expectancy ≥ 3 months. * ECOG Performance Status of 0-1. * Histologically confirmed hepatocellular carcinoma (without fibrolamellar subtype). * Not a candidate for curative treatments. * Child-Pugh A. * Hematological, Biochemical and Organ Function: * AST (SGOT): ≤ 5.0 × ULN * ALT (SGPT): ≤ 5.0 × ULN * Total Bilirubin: ≤ 3.0 × ULN * Platelets: ≥ 50,000/μL * Absolute Neutrophil Count: ≥ 1,500/μL * Serum creatinine: ≤ 2.0 × ULN * PT-INR: ≤ 2.0 * IHC confirmed GPC3-positive HCC tumor tissue. Tumor tissue sample may be provided by: * A formalin fixed paraffin embedded block sample within 12 months prior to informed consent for HCC diagnosis; * Unstained slides obtained within 3 months prior to informed consent for HCC diagnosis; * Undergo biopsy to confirm GPC3-positive HCC. * Resection samples are not acceptable. * At least one measurable lesion based on Response Evaluation Criteria In Solid Tumors criteria. Exclusion Criteria: * Child-Pugh C. * Pregnant or lactating women or women of child-bearing potential and men of childbearing potential not willing to use effective means of contraception. * Patients known to be positive for Human immunodeficiency virus infection. * Active infectious diseases requiring treatment except for hepatitis B and C. * Other malignancies within the last 5 years. * History of transplantation (organ, bone marrow transplantation,peripheral blood stem cell transplantation, etc.). * Patients with significant concomitant disease determined by the investigator to be potentially aggravated by the investigational drug. * Patients with brain metastases, other central nervous system or other psychiatric disease. * Patients who received major surgery, local therapy for HCC, chemotherapy, radiotherapy, hormone-therapy, immunotherapy, or another investigational drug within 4 weeks prior to Day 1. * Patients who received the following treatments within 2 weeks prior to Day1: * Anticoagulant or thrombolytic agents for therapeutic purposes. * Systemic anti-viral therapy for hepatitis C/cirrhosis. * Blood transfusion * History of hypersensitivity to similar agents. * Patient is unable to comply with the requirements of the protocol and/or follow-up procedures. (Extension Phase) * Child-Pugh B or C. * Pregnant or lactating women or women of child-bearing potential and men of childbearing potential not willing to use effective means of contraception. * Patients known to be positive for Human immunodeficiency virus infection. * Active infectious diseases requiring treatment except for hepatitis B and C. * Other malignancies within the last 5 years. * History of transplantation (organ, bone marrow transplantation, Peripheral blood stem cell transplantation, etc.). * Patients with significant concomitant disease determined by the investigator to be potentially aggravated by the investigational drug. * Patients with brain metastases, other central nervous system or other psychiatric disease. * Patients who received major surgery, local therapy for HCC, chemotherapy, radiotherapy, hormone-therapy, immunotherapy, or another investigational drug within 4 weeks prior to Day 1. * Patients who received the following treatments within 2 weeks prior to Day 1: * Anticoagulations or thrombolytic agents for therapeutic purposes. * Systemic anti-viral therapy for hepatitis C/cirrhosis. * Blood transfusion * History of hypersensitivity to similar agents. * Patient is unable to comply with the requirements of the protocol and/or follow-up procedures. * IHC confirmed GPC3-negative HCC tumor tissue.