An ongoing phase II study is currently evaluating the combination of niraparib with PD-1 blockade (dostarlimab) in patients with recurrent/metastatic HNSCC, with primary endpoints including stable disease, partial or complete response, and secondary endpoints including adverse events, progression-free survival (PFS) and overall survival (OS) [212]. This evidence concerns the gene PDCD1 and head and neck squamous cell carcinoma.