Patients with R/M HNSCC who failed at least one line of prior treatment including a PD-1 inhibitor and for whom no surgical or radiation curative options existed were eligible for the study. Patients received niraparib (200 mg daily) beginning one week prior to initiation of dostarlimab (500 mg q3wks x4 followed by 1000 mg q6wks)....The patient with a PR remains on treatment past 24 months, was PD-L1 positive, had low TMB and no DDR deficiency.