CSF2 and melanoma: In 2015, the OPTiM trial led to the approval of intralesional talimogene laherparepvec in patients with surgically unresectable stage III or IV melanoma.40,41,42 The durable response rate (lasting >6 months) was 16.3% in the talimogene laherparepvec group compared with 2.1% in the group receiving granulocyte-macrophage colony-stimulating factor.