Xilio Therapeutics Presents Promising Preclinical Tumor-Selective Efficacy and Safety Data for XTX201 (IL-2) and XTX101 (anti-CTLA-4) at SITC

- XTX201 (IL-2 agonist) and XTX101 (anti-CTLA-4 antibody) showed significant anti-tumor effects with minimal peripheral effects in tumor-bearing mice

- XTX201 (IL-2 agonist) was well-tolerated in non-human primates with no evidence of systemic toxicities associated with approved IL-2 therapy

- Data support a wide therapeutic index for both molecules

- Investigational New Drug applications will be submitted for both XTX201 and XTX101 in 2021

WALTHAM, Mass.--(BUSINESS WIRE)--Xilio Therapeutics, a biotechnology company developing potent, tumor-selective immunotherapies for patients with cancer, today announced the presentation of preclinical data of its lead investigational therapies: XTX201, a tumor-selective IL-2, and XTX101, a tumor-selective anti-CTLA-4 antibody. The findings were presented at the 35th Annual Meeting of The Society for Immunotherapy of Cancer (SITC 2020).

“This is a transformational moment for the company. These positive preclinical data showing tumor-selective activity with our most advanced therapeutic candidates, XTX201 and XTX101, support the evaluation of both molecules in clinical studies, bringing us one step closer to delivering transformative cancer treatments for patients. Based on these findings, we hope to submit Investigational New Drug applications for both molecules in 2021,” said Rene Russo, Chief Executive Officer of Xilio Therapeutics.

XTX201 is a protein-engineered IL-2 agonist, and XTX101 is an Fc-engineered anti-CTLA4 monoclonal antibody. Both are novel molecules designed to bind their targets preferentially in tumors while minimizing activity in healthy non-tumor tissues. The new data demonstrate preclinical proof-of-concept for these molecules with significant anti-tumor effects and minimal peripheral effects in animal models, significantly widening the potential therapeutic index for these therapies vs. currently available treatments.

Abstracts and presentations at SITC 2020

• XTX201, a protein-engineered IL-2, exhibits tumor-selective activity in mice without peripheral toxicities in non-human primates (Poster Presentation, Abstract #568)

• Tumor-activated Fc-engineered anti-CTLA-4 monoclonal antibody, XTX101, demonstrates tumor-selective PD and efficacy in preclinical models (Oral Presentation, Abstract #587)

About Xilio Therapeutics

Xilio Therapeutics is a biotechnology company that uses its proprietary technology to develop next-generation cancer immunotherapies. Our product candidates are engineered to unleash the power of the immune system selectively at the site of the tumor. Thus, we have designed them to maximize efficacy while overcoming the significant toxicities associated with clinically validated immuno-oncology (IO) therapies, such as IL-2 and anti-CTLA4. The broad applicability of these therapies across cancer types means that a significant number of patients could benefit from these potentially curative medicines.

Xilio was founded in 2016 and is headquartered in Waltham, Mass. For more information, please visit www.xiliotx.com.