In summary, antitumor activity in response to DuoBody-CD3x5T4 treatment was associated with peripheral blood PD markers, including T-cell activation and increased plasma cytokine levels, in addition to intratumoral PD markers such as T-cell activation, T-cell proliferation, and production of IFNγ and GZMB in the tumor. This evidence concerns the gene GZMB and neoplasm.