Induction and Maintenance Treatment With PARP Inhibitor and Immunotherapy in HPV-negative HNSCC

"For all patient's population:~* Niraparib 200 mg/day: day -49 to day -21;~* Dostarlimab 500 mg iv: day -49 and day -28; At day -21, clinical evaluation will be performed and the patient will be directed to surgery with exclusion from the study in case of progressive disease. Radiological assessment will be performed according to the physician's judgement.~If no clinical evidence of disease progression:~* Niraparib 200 mg/day: day -21 to day -7~* Dostarlimab 500 mg iv: day -7~* Radiological assessment (day -1, ± 3 days),~* Surgery (original margin) at day 0 (±3 days)~* Standard postoperative (chemo)radiotherapy according to pathologic report;~* Maintenance Niraparib, 200 mg/day for 6 months~* Maintenance Dostarlimab, 500 mg iv q3W for the first four cycles and 1000 mg iv Q6W thereafter for 3 months."