The issues facing engineered (modified) oncolytic viruses are significant since they must address both patient safety and product effectiveness in the course of their development. On one hand a pathogenic oncolytic virus intended to treat cancer patients needs to be modified so that it does not infect healthy cells and only infects tumor cells. However, if a virus is modified too much, its infectivity is severly compromised..
On the other hand, if not modified enough, potency then becomes an issue, so these engineered oncolytic viruses try to solve this by looking to add multiple cytokines as payloads on to the structure of these viruses, or only have one cytokine that is extra-potent. However, if a payload is too strong, it results in the immune system over-reacting, leading to safety issues.
Furthermore these attenuated "engineered" viruses must be made so that they retain their ability to multiply and infect the tumor cells — and to accomplish this they must have the appropriate payload attached - one which can exhibit viral potency that is strong enough to invoke the patient’s immune response, yet not so strong that you get this cytokine storm. And this is difficult for an engineered (attenuated/modified) virus to accomplish, particularly when used in multiple and different cancers.
Consequently, ONCY's non-pathogenic, naturally occurring oncolytic virus and IMMUNE MOLECULE PLATFORM TECHOLOGY pelareorep does not have these issues of patient safety and effectiveness, and can be used to treat multiple/different cancers in combination with other I/O therapies including immune checkpoint inhibitors, CAR-T therapies, bispecifics, CDK4.6 and PARP inhibitors and other small molecules, for example.