Tebentafusp-tebn is a bispecific gp100 peptide-HLA-A02:01 directed T cell receptor CD3 T cell engager. The TCR arm binds to a gp100 peptide presented by human leukocyte antigen-A*02:01 (HLA¬ A02:01) on the cell surface of uveal melanoma tumor cells. In vitro, tebentafusp-tebn bound to HLA-A02:01-positive uveal melanoma cells and activated polyclonal T cells to release inflammatory cytokines and cytolytic proteins, which results in direct lysis of uveal melanoma tumor cells.