Similarly, the EAGLE (NCT02369874) and Checkmate 651 (NCT02741570) trials, respectively, failed to display longer OS in HNSCC patients treated with durvalumab plus tremelimumab versus standard of care and nivolumab (anti-PD-1) plus ipilimumab (anti-CTLA-4) versus the EXTREME regimen.25 Here, PDCD1 is linked to head and neck squamous cell carcinoma.