About XTX501

Xilio is leveraging its proprietary, clinically validated tumor-activation platform to advance XTX501, a novel masked bispecific PD-1/IL-2 designed to selectively stimulate PD-1 positive, antigen-experienced T cells and enhance their function. XTX501 incorporates masking designed to overcome IL-2 receptor-mediated clearance and peripheral activity. In preclinical studies, XTX501 demonstrated robust monotherapy activity (including settings insensitive to PD-1) and tumor-selective pharmacodynamics consistent with its intended mechanism of action.