CTLA4 and head and neck squamous cell carcinoma: FDA approval has been granted for the combined administration of Ipilimumab (targeting CTLA-4) and Nivolumab (targeting PD-1) for the treatment of melanoma (NCT01844505, NCT01927419),669–671 renal cell carcinoma (RCC) (NCT02231749),672 non-small-cell lung cancer (NSCLC) (NCT02477826),673 head and neck squamous cell carcinoma (HNSCC) (NCT02319044)674 and colorectal cancer (CRC) (NCT02060188).675 Melanoma was the first tumor type to receive approval for treatment with the dual combination of ICB.