Imlygic (granulocyte-macrophage colony-stimulating factor (GM-CSF)-armed, herpes simplex virus type 1 (HSV10)), which was approved by the US and EU FDAs in 2015 and by the AUS FDA in 2016 [43,44], remains the only internationally available OV with a proven clinical track record as a monotherapy against melanoma [45]. The gene discussed is CSF2; the disease is melanoma.