dostarlimab + belrestotug

Dostarlimab + belrestotug is a combination of two monoclonal antibodies developed for the treatment of cancer, specifically non-small cell lung cancer (NSCLC) and head and neck squamous cell carcinoma (HNSCC). Dostarlimab is an anti–PD-1 antibody that blocks the programmed death-1 receptor on T cells, thereby enhancing immune-mediated tumor cell killing. Belrestotug (formerly EOS-448 or GSK4428859A) is an Fc-active human IgG1 monoclonal antibody targeting TIGIT, an inhibitory receptor that suppresses adaptive and innate immune responses against tumors. The rationale for combining these agents was to achieve synergistic immunomodulation by simultaneously blocking PD-1 and TIGIT pathways to enhance antitumor immunity. Clinical trials showed improved objective response rates compared to monotherapy but failed to demonstrate a meaningful benefit in progression-free survival; as a result, development has been discontinued.