Clinical development of reovirus for cancer therapy: An oncolytic virus with immune-mediated antitumor activity

Area of Science:

• Virology
• Oncology
• Immunology

Background:

• Reovirus is a double-stranded RNA virus exhibiting oncolytic activity, meaning it preferentially replicates in cancer cells.
• The virus's oncolytic efficacy is influenced by activated Ras signaling pathways within cancer cells.
• Immune responses to reovirus play a complex role, potentially hindering tumor targeting but also contributing to therapeutic benefits.

Purpose of the Study:

• To review the development of reovirus as an anticancer agent.
• To summarize preclinical findings on the anticancer activity of wild-type reovirus (Reolysin®).
• To present clinical data from 22 trials investigating reovirus therapy.

Main Methods:

• Review of preclinical studies demonstrating reovirus's anticancer effects.
• Analysis of the viral life cycle in Ras-transformed cells.
• Compilation and review of clinical trial data for reovirus therapy.

Main Results:

• Reovirus demonstrates preferential replication and oncolysis in cancer cells, partly due to Ras signaling.
• Ras-transformation enhances reovirus oncolysis by impacting multiple stages of the viral life cycle.
• Preclinical studies confirm broad anticancer activity of unmodified type 3 Dearing strain reovirus (Reolysin®) across various cancers.

Conclusions:

• Reovirus exhibits significant oncolytic potential, supported by preclinical evidence.
• Clinical data from 22 trials will be reviewed to assess its therapeutic development.
• Reovirus represents a promising candidate for anticancer therapy, with its efficacy modulated by host cell signaling and immune interactions.