The CF33, Vaxinia and Oncarlytics Deal, page-1079

@bat35y I'm definitely not qualified to give any greater explanation than what I've already provided however, I'm not too bad at finding information...

So have a read of some explanations provided by others who are qualified:

Oncolytic virotherapy: basic principles, recent advances and future directions | Signal Transduction and Targeted Therapy (nature.com)

A comprehensive preclinical study supporting clinical trial of oncolytic chimeric poxvirus CF33-hNIS-anti-PD-L1 to treat breast cancer - PMC (nih.gov)




Oncolytic Viruses: Newest Frontier for Cancer Immunotherapy - PMC (nih.gov)


There are multiple ways in which the body clears the virus and not all because of a specific response to the virus, so a bigger dose should keep it active in the body longer and as @reon1 mentioned, CF33 is unlikely to be hugely immunogenic, so probably not much of an immune memory for the virus meaning there is not a swift response when dosed on subsequent occasions.

With all that said and done, the results we've been advised of to date shows that in small to medium doses CF33 is capable of infecting cancer cells resulting in the clearance of the cancer from the patients' body. A bigger dose should have an even better response.

After reading the second screenshot I posted above, I think it they may also consider trialling treating patients both via IV and IT where possible, to ensure the maximum amount of virus is delivered to as many tumour sites as possible to provide the greatest opportunity for it to be effective.