Ghassan Abou-Alfa, MD
The findings from the ongoing phase III PHOCUS trial could demonstrate that sorafenib (Nexavar) plus immunotherapy with the oncolytic virus Pexa-Vec is another effective systemic therapy for patients with hepatocellular carcinoma (HCC), explained Ghassan K. Abou-Alfa, MD.
, Abou-Alfa discussed the potential of the oncolytic virus Pexa-Vec and other developments in HCC.
OncLive: Could you provide an overview of the PHOCUS trial?
: It's a phase III trial that is looking at a vaccinia virus-based treatment that has a thymidine kinase, which is altered inside the vaccinia that we inject directly into the tumor. Original work has shown there are quite intriguing and evaluable responses in the tumors. However, it was understood that in combination with sorafenib, it will be better. Thus, the current trial is looking at Pexa-Vec followed by sorafenib and randomized against the standard of care, which is sorafenib. The trial is, thankfully, going all over the world and accruing very well. We very much look forward to seeing what the results will be.
How could positive results of this study affect clinical practice?
I don't like to answer speculative questions. It's hard to say what's going to happen with the study.
Pexa-Vec causes, number one, direct tumor destruction; number two, the ability of the vaccinia to transmit from 1 place to another and affect other tumors, and add to this the altered immune mechanism with the activation of the G-CSF; and third, the antiangiogenic component makes it a multitargeted approach to therapy. The fact that we are affecting the tumors directly by injecting them, but [also] the ability to transfect other tumors definitely is intriguing. We'll just have to wait for the results.
What are some other key areas of research in HCC right now?
We have 6 trials that have shown positive results. Of that, we already have drugs approved by the FDA, including lenvatinib in the first-line setting, regorafenib in the second-line setting, and the conditional approval for nivolumab in the second-line setting. At the moment, the immediate action is to await results from the large phase III trial of the checkpoint inhibitors: first-line nivolumab, second-line pembrolizumab (Keytruda), and durvalumab (Imfinzi) plus tremelimumab in the first-line setting.
... to read the full story