Testing a new cancer treatment after standard therapy for head and neck cancer

This study is testing a medication called dostarlimab to see if it can help people with locally advanced head and neck squamous cell carcinoma (a type of cancer that starts in the cells lining the mouth, throat, or voice box). You would receive this medication after you've already completed standard chemotherapy and radiation treatment. The goal is to find out whether this treatment is safe and whether it works better than a placebo (a dummy medication) at preventing the cancer from coming back.

Even after standard chemotherapy and radiation, head and neck cancer can return in some patients. This medication works by helping your immune system recognize and fight cancer cells, and researchers want to learn if adding this treatment after standard therapy can improve outcomes and give patients a better chance of staying cancer-free.