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.