Table 1.

Summary of characteristics of studied oncolytic herpesviruses. Abbreviations: HSV-1 = herpes simplex virus type 1. GALV-GP-R−: A codon-optimized version of a potent fusion membrane glycoprotein (GP) from gibbon ape leukemia virus (GALV). * anti-mouse CTLA-4 antibody-like molecule or mouse CD40L, mouse OX40L or mouse 4-1BBL.

T-VEC	RP1	HF-10
Selection of HSV-1 JS1 strain enhances selective targeting of tumor cells	Selection of HSV-1 RH018 strain offers increased cytotoxicity against tumor cells	Deletion in the Bam HI-B fragment
ICP34.5 gene deletion permits viral replication in tumor cells by attenuating the natural neurovirulence of the virus	ICP34.5 gene deletion permits viral replication in tumor cells by attenuating the natural neurovirulence of the virus	Non-expression of UL56 reduces neurovirulence of HSV without affecting viral replication in vitro
ICP47 gene deletion inhibits suppression of antigen presentation and upregulates HSV1 US11 gene	ICP47 gene deletion inhibits suppression of antigen presentation and upregulates HSV US11 gene	Reduced expression of UL43, UL49.5, UL55, and LAT reduces neurovirulence and enhances cell killing
HSV-1 US11 gene augments viral replication in tumor cells without impairing tumor selectivity	HSV US11 gene augments viral replication in tumor cells without impairing tumor selectivity	Increased expression of UL53 and UL54
	Expression of GALV-GP-R− * enhances systemic killing of tumor cells
GM-CSF cassette initiates systemic immune response against tumor	GM-CSF cassette initiates systemic immune response against tumor
	Expression of anti-CTLA-4 or immune co-stimulatory pathway activating ligands * further enhances systemic immune response