Do You Know About Oncolytic Virus? It’s an Excellent Tool for Cancer Immunotherapy
In this article you also read about the clinical outcomes and a brand new global industry collaboration in this area.
“Virotherapy is currently undergoing a renaissance, based on our improved understanding of virus biology and genetics and our better knowledge of many different types of cancer. Viruses can be reprogrammed into oncolytic vectors by combining three types of modification: targeting, arming and shielding”.
Excerpt from Nature Reviews Microbiology
Mechanism of dual-action cancer therapy
The potential of oncolytic viruses as anti-cancer and oncolytic immunotherapy agents are well recognized as they act through multi-mechanism such as multimodal immunogenic cell death (ICD), autophagy and induction of adaptive antitumor immunity. Below is the illustration of how it works;
Figure 1. The mechanism of dual-action cancer therapy (Credit: CaptainVivacious/Wikipedia)
Categories of Oncolytic Viruses
Depending upon the genetic element composition, oncolytic viruses are divided into-
single- or double-stranded DNA
or RNA types.
Number of viruses were already clinically tested for their potential as therapeutic oncolytic agents.
On October, 27, 2015, The U.S. Food and Drug Administration (FDA) approved talimogene laherparepvec (brand name: Imlygic) as the first FDA-approved oncolytic virus therapy, for the treatment of melanoma lesions in the skin and lymph nodes. It was developed by BioVex, Inc. under the name OncoVEXGM-CSF, which in 2011 was acquired by Amgen. It is based on oncolytic HSV1-expressing granulocyte macrophage colony-stimulating factor (GM-CSF). Please see Figure 1.
JX-594 (also known as Pexa-Vec) is another oncolytic virus being develop by Jennerex and partners- Transgene S.A., Lee’s Pharmaceutical Holdings Ltd. and Green Cross Corp. It already has orphan drug designation from FDA and EUMA for the treatment of hepatocellular carcinoma (HCC). Currently, a global Phase III trial (the PHOCUS trial) is under the process for the enrollment of patients with advanced stage hepatocellular carcinoma.
Reolysin® (pelareorep; Wild-Type Reovirus) is another oncolytic virus being developed by Oncolytics Biotech for the treatment of various cancers and cell proliferative disorders. It also has Orphan Drug Designation granted (in April 2015) by FDA for the treatment of malignant glioma. It has successfully completed number of Phase I and II clinical trials and are currently being evaluated for several cancers in Phase II and III.
New Industry Collaboration
With the aim of an ideal cancer drug that selectively destroy tumor cells while concurrently enhancing patient’s immune system ability to further kill residual tumor cells that survived initial virus attack, the two companies; Profectus Biosciences, Inc. (a clinical vaccine development company) and Vyriad (a clinical stage oncolytic immuno-virotherapy development company) recently collaborated with their respective recombinant vesicular stomatitis virus (rVSV) derived oncolytic and vaccine technologies.
Figure 1. Explanation of the mechanism of action of talimogene laherparepvec, an oncolytic immunotherapy. (Credit: CaptainVivacious/Wikipedia)
Figure (Categories of Oncolytic Viruses): adaptation from Nature Reviews Drug Discovery
Featured Image: graphics mixed by medgenera. Virus cell isometric 3d icon © JuliarStudio (Stock Photo ID: 115091753)