In fact, a recent paper reported a novel mechanism by which PD-L1 non-blocking anti-PD-1 mAbs can show favorable anti-tumor activity.[24] In another recent publication, researchers describe a set of potent macrocyclic peptide and small-molecule PD-1/PD-L1 inhibitors, one of which induced cytokine production (IL-2 and IFN-γ) and T cell proliferation at levels comparable to pembrolizumab.[25] We suspect the unique binding properties observed for many of the antibodies studied here will translate to similarly unique biological activity at the cellular and potential therapeutic level. The gene discussed is PDCD1; the disease is neoplasm.