Xilio Therapeutics Highlights Recent Advances Across Clinical Pipeline and Encouraging Preliminary Phase 1 Safety Data for XTX301, a Tumor-Activated IL-12, Further Validating the Promise of Its Tumor-Activated Immuno-Oncology Therapies - Seite 2

Report initial Phase 2 data for XTX101 in combination with atezolizumab in approximately 20 patients with MSS CRC in the fourth quarter of 2024 and in approximately 20 additional patients (40 patients total) in the first quarter of 2025.

XTX202 (tumor-activated, beta-gamma biased IL-2)

• Xilio continues to enroll patients at the 4.0 mg/kg dose in its ongoing Phase 2 monotherapy trial for XTX202 in patients with metastatic renal cell carcinoma or unresectable or metastatic melanoma.
  
  
• Based on recently accelerated enrollment, Xilio now plans to report Phase 2 monotherapy data for XTX202 in approximately 20 patients treated at the 4.0 mg/kg dose by the end of the first quarter of 2024.
  

XTX301 (tumor-activated IL-12)

• Xilio today announced encouraging preliminary safety data from its ongoing Phase 1 trial evaluating XTX301 as a monotherapy in dose escalation in patients with advanced solid tumors.
  
  
  • As of a data cutoff date of January 5, 2024, nine patients had been treated with XTX301 in the outpatient setting in Phase 1 dose escalation at three dose levels ranging from 5 ug/kg to 45 ug/kg administered once every three weeks.
    
    
  • XTX301 was generally well-tolerated across all dose levels with no dose-limiting toxicities observed in patients as of the data cutoff date.
    
    
• Subject to obtaining sufficient additional capital, Xilio today reaffirmed plans to report Phase 1 safety, pharmacokinetic and pharmacodynamic data for XTX301 in patients with advanced solid tumors in the second half of 2024.
  

Financial Guidance

Xilio continues to anticipate that its existing cash and cash equivalents will be sufficient to fund its operating expenses and capital expenditure requirements into the end of the second quarter of 2024.

About XTX101 (anti-CTLA-4) and the Phase 1/2 Combination Clinical Trial

XTX101 is an investigational tumor-activated, Fc-enhanced, high affinity binding anti-CTLA-4 monoclonal antibody designed to block CTLA-4 and deplete regulatory T cells when activated (unmasked) in the tumor microenvironment (TME). In the third quarter of 2023, Xilio entered into a co-funded clinical trial collaboration with Roche to evaluate XTX101 in combination with atezolizumab (Tecentriq) in a multi-center, open-label Phase 1/2 clinical trial. Xilio is currently evaluating the safety and tolerability of the combination in patients with advanced solid tumors in the Phase 1 dose escalation portion of the clinical trial. Subject to obtaining sufficient additional capital and the results of Phase 1 combination dose escalation, Xilio plans to evaluate the safety and efficacy of the combination in the Phase 2 portion of the clinical trial in patients with microsatellite stable colorectal cancer (MSS CRC). Please refer to NCT04896697 on www.clinicaltrials.gov for additional details.