KEY

Inclusion Criteria:

- Diagnosis of primary HCC by tissue biopsy (histological/cytological diagnosis), or
clinical diagnosis

- Previously treated with sorafenib for ≥ 14 days and has discontinued sorafenib
treatment at least 14 days prior to randomization due to either intolerance or
radiographic progression NOTE: Sorafenib is NOT required to be the most recent
treatment received for HCC

- ECOG performance status 0, 1 or 2

- Child-Pugh Class A; or Child-Pugh Class B7 without clinically significant ascites

- Hematocrit ≥30% or Hemoglobin ≥10 g/dL

- Tumor status: Measurable viable tumor in the liver and injectable under
imaging-guidance; At least one tumor in the liver that has not received prior
local-regional treatment OR that has exhibited >25% growth in viable tumor size since
prior local-regional treatment.

KEY Exclusion Criteria:

- Received sorafenib within 14 days prior to randomization

- Received systemic anti-cancer therapy other than sorafenib within 28 days of
randomization

- Prior treatment with JX-594

- Platelet count < 50,000 PLT/ mm3

- Total white blood cell count < 2,000 cells/mm3

- Prior or planned organ transplant

- Known significant immunodeficiency due to underlying illness (e.g. HIV/AIDS) and/or
medication

- Severe or unstable cardiac disease

- Viable CNS malignancy associated with clinical symptoms

- Pregnant or nursing an infant

- History of inflammatory skin condition (e.g., eczema requiring previous treatment,
atopic dermatitis)