SR-8541A + botensilimab + balstilimab

SR-8541A + botensilimab + balstilimab is a combination cancer immunotherapy regimen under investigation primarily for solid tumors, including microsatellite stable metastatic colorectal cancer and breast cancer. SR-8541A is an orally bioavailable small-molecule inhibitor of ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), designed to activate the STING pathway, promote immune cell infiltration, and inhibit tumor growth. Botensilimab (AGEN1181) is a multifunctional, Fc-enhanced anti-CTLA-4 monoclonal antibody, engineered to enhance both innate and adaptive anti-tumor immune responses by depleting regulatory T cells and activating myeloid cells within the tumor microenvironment. Balstilimab (AGEN2034) is a fully human monoclonal antibody that blocks PD-1, aiming to restore T-cell activity by preventing PD-1 interaction with its ligands PD-L1 and PD-L2. This combination seeks to synergize innate immune activation (via ENPP1 inhibition and STING pathway) with dual checkpoint blockade (CTLA-4 and PD-1) to drive anti-tumor immunity, especially in immunologically “cold” or refractory cancers[1][2][3][4][7].