Talimogene laherparepvec (T-VEC), another OV therapy, received US FDA approval for the treatment of non-resectable metastatic melanoma in 2015 [30] and subsequently got approved for treatment of locally advanced or metastatic cutaneous melanoma in Europe, showing promising efficacy as a single agent and in combination with PD-1 inhibitor pembrolizumab [31]. The gene discussed is PDCD1; the disease is metastatic melanoma.