The recombinant virus used in the AuRx therapy has been genetically engineered to remove a gene that is responsible for the ability of the virus to activate signaling pathways which cause cell proliferation and ultimately may result in neoplastic transformation. The deleted gene is also required for HSV-2 replication and reactivation from ganglionic latency. Therefore, the recombinant virus used in the AuRx therapy has been attenuated to prevent the outbreak of the disease in previously infected individuals.

Since there is a 50% similarity (genetic homology) between HSV-l and HSV-2, it is likely that the vaccine will also prevent HSV-1 recurrences, however, demonstrating this will require a large clinical trial over an extended period of time.