PDCD1 and head and neck squamous cell carcinoma: These results led to Phase II trials in both prostate cancer as a neoadjuvant (NCT02923180) and head and neck squamous cell carcinoma (HNSCC) in combination with other ICBs namely retifanlimab (anti-PD-1) and tebotelimab (anti-CTLA-4) (NCT04634825).