||This article may be too technical for most readers to understand. (August 2012)|
JX-594 is an oncolytic virus (also known as Pexa-Vec) developed by Jennerex and partners: Transgene S.A.; Lee's Pharmaceutical Holdings Ltd.; and Green Cross Corp. Pexa-Vec is designed to target and destroy cancer cells.
JX-594 is a vaccinia poxvirus engineered by addition of the GM-CSF gene and deletion of the thymidine kinase gene which limits viral replication to cells with high levels of thymidine kinase, typically seen in cancer cells with a mutated RAS or p53 gene. The virus kills them by lysis and also expresses GM-CSF which may help initiate an anti-tumour immune response. 
Early results, in Nov 2011, from a small (30 patient) phase II trial in advanced hepatocellular carcinoma (HCC) showed an increased median overall survival of 13.8 months compared 6.7 months for a lower dose (p=0.029).
- Jennerex Granted FDA Orphan Drug Designation for Pexa-Vec in Hepatocellular Carcinoma (HCC)
- Un virus contre le cancer 25 March 2012, Radio Canada (French)
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