Xilio is focused on developing cytokines with exemplary clinical activity and tolerability. We are developing XTX301, a tumor-activated, engineered IL-12, for the treatment of advanced solid tumors.


About IL-12

IL-12, or Interleukin-12, has emerged as one of the most potent cytokine mediators of antitumor activity because of its multiple effects on different immune cells in the tumor microenvironment (TME). IL-12 has the ability to activate and bridge both innate (natural killer or NK cell) and adaptive (cytotoxic CD8+ T and CD4+ T cells) immunity for tumor cell killing while further coordinating additional anti-cancer defenses such as regulatory T-cell suppression and anti-angiogenic effects. Despite research across the field suggesting that IL-12 can significantly benefit patients in fighting cancer, there are currently no approved IL-12 agents due to severe systemic toxicity with unmodified IL-12.


XTX301, a tumor-activated, engineered IL-12

XTX301 is an investigational tumor-activated, engineered IL-12 molecule designed to potently stimulate anti-tumor immunity and reprogram the TME of poorly immunogenic “cold” tumors towards an inflamed or “hot” state.

XTX301 is currently being evaluated in an ongoing Phase 1 clinical trial as a monotherapy in patients with advanced solid tumors. Significant potential also exists to explore the development of XTX301 in combination with other agents and modalities.

About the Phase 1 Clinical Trial for XTX301

The Phase 1 clinical trial for XTX301 is a first-in-human, multi-center, open-label trial designed to evaluate the safety and tolerability of XTX301 as a monotherapy in patients with advanced solid tumors. Please refer to NCT05684965 on www.clinicaltrials.gov for additional details.

XTX301 Presentations and Publications

XTX301 Poster Presentation at the 2023 American Society of Clinical Oncology (ASCO) Annual Meeting
A first-in-human study of XTX301, a masked, tumor-activated interleukin-12 (IL-12) in patients with advanced solid tumors

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XTX301 Poster Presentation at the American Association for Cancer Research (AACR) 2023 Annual Meeting
A half-life extended, tumor-activated IL-12 increased the infiltration of effector immune cells into the tumor microenvironment and demonstrated anti-tumor activity in syngeneic mouse models

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XTX301 Poster Presentation at the New York Academy of Sciences’ Frontiers in Cancer Immunotherapy 2022 Conference
A half-life extended, tumor selective IL-12 activated tumor infiltrating immune cells and demonstrated anti-tumor activity in the MC38 syngeneic mouse model

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XTX301 Poster Presentation at the Society for Immunotherapy in Cancer’s 36th Annual Meeting (SITC)
XTX301, A Protein-engineered IL-12, Exhibits Tumor-selective Activity In Mice Without Peripheral Toxicities And Is Well Tolerated In Non-Human Primates

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