A Phase 2b Study of Modified Vaccinia Virus to Treat Patients Advanced Liver Cancer Who Failed Sorafenib

This Phase 2b, open-label, randomized, multi-center study is designed to evaluate the efficacy and safety of JX-594 (Pexa-Vec) in patients with advanced hepatocellular carcinoma (HCC) who have previously failed sorafenib treatment. Eligible patients are randomly assigned in a 2:1 ratio to receive either the experimental therapy (JX-594 plus Best Supportive Care \[BSC\]) or the control therapy (BSC alone). Patients assigned to the experimental arm receive an initial intravenous (IV) infusion of JX-594 on Day 1. This is followed by intratumoral (IT) injections of JX-594 directly into viable liver tumors under imaging guidance on Day 8, Day 22, and Weeks 6, 12, and 18. These patients will also receive BSC, but active anti-cancer treatments are strictly prohibited. In contrast, patients in the control arm receive only Best Supportive Care (e.g., hydration, nutrition, pain management) at the treating physician's discretion without any study drug injections. Experimental or active anti-cancer therapies are not permitted in the control arm. The primary objective of this study is to compare the Overall Survival (OS) between the two treatment arms. Secondary objectives include evaluating Time-to-Tumor Progression (TTP) and objective response rate based on mRECIST criteria for HCC. The study also evaluates Time-to-Symptomatic Progression (TSP), which is defined by changes in the FACT Hepatobiliary Symptom Index (FHSI-8) questionnaire and ECOG performance status. Additionally, the study assesses changes in Quality of Life (QoL) measured by EORTC and FACT-Hep questionnaires. Finally, overall safety and tolerability are closely monitored through the incidence and severity of Adverse Events (AEs) and Serious Adverse Events (SAEs) graded according to NCI CTCAE v4.03, along with clinical laboratory evaluations.