An Open-Label, Multiple-Center, Phase IIa/IIb Clinical Trial to Evaluate the Efficacy, Safety and Tolerability of VG161 as Monotherapy and in Combination With Nivolumab for Treatment of Patients With Hepatocellular Carcinoma or Intrahepatic Cholangiocarcinoma

Safety Run-in Cohort (cohort 1): 10 patients will be treated with IT injection of VG161 in the cohort 1 at dose level of 1.0x10E8 PFU x 3 days. Monotherapy Cohorts (Cohort 2 and 3) Cohort 2 (HCC) This part is a single-agent, single one-dose level and single-arm design. Approximately 39 subjects will be enrolled in the study to receive VG161. In the first stage, 21 subjects will be enrolled. If there is only 1 or fewer subjects has been observed with objective response and no more than 12 (\<13) subjects have PFS longer than 3 months, the trial will be stopped. Otherwise, this study will continue to enter the second stage, and 18 additional subjects will be added, and the total number of trial subjects will reach 39. Cohort 3 (ICC) This part is a single-agent, single one-dose level and single-arm design. The trial will be carried out in two periods. In the first period, a total of 20 subjects will be enrolled. If there is only 1 or fewer response case in the 20 subjects, the trial will be stopped to investigate the efficacy of the IP, otherwise, subjects will continue to enter the second period, and 13 additional subjects will be added, and the total number of trial cases will reach 33. Cohort 4 (ICC and HCC) Combination with Nivolumab Combination cohort and subjects will receive VG161 at the same schedule as the monotherapy cohorts and 240 mg of intravenous Nivolumab on days 8 and 15 of each treatment cycle. The Nivolumab dose can be changed to 480 mg every 4 weeks after cycle one based on investigator's discretion.