- Prior treatment with immune-modulatory agents including, but not limited to: IL-2 (interleukin-2), CTLA-4 (cytotoxic T-lymphocyte-associated protein 4) blockade, PD-1 (Programmed cell death protein 1) /PD-L1 (Programmed cell death protein ligand 1) blockade, CD40 (cluster of differentiation 40) stimulation, or CD137 (tumor necrosis factor receptor superfamily member 9) stimulation.