These data were consistent with other studies that employed different OVs in combination with ICIs, which achieved positive results.60–62 Other strategies combining an αPD-1 antibody with 4-1BB agonists have also shown increased therapeutic potential in subcutaneous CT26 colon carcinoma and B16F10 melanoma.63 64 Interestingly, these approaches have shown that PD-1 blockade increases 4-1BB expression in CD8+ T cells and that an anti-4-1BB antibody conversely induces PD-1 expression, which suggests a potential synergistic effect from the combination approach. This evidence concerns the gene CD8A and melanoma.