Interestingly, at lower MOIs (0.1 and 1 pfu/cell), THV_ADA and THV_ADA-SP resulted in being even more cytotoxic than the unarmed R-LM113, presumably due to the deprivation of eADO, known to sustain cancer cell viability (Figure 3a) [14,29,30]. The gene discussed is ADA; the disease is cancer.