157 Background: Persistence of activated CD8 T cells is essential for the durability of tumor immune responses. IL-10 is an anti-inflammatory cytokine, PEGylated IL-10 (AM0010) enhances tumor specific CD8 T cell expansion and cytotoxicity. We evaluated tolerability and efficacy of AM0010 alone, with chemotherapy or anti-PD-1 in a phase 1 study. AM0010 alone induces objective anti-tumor responses without auto-immune toxicities. AM0010 with anti-PD-1 was evaluated in RCC (n=8) or NSCLC (n=5)...