Exhibit 99.1
Xilio Therapeutics Announces Pipeline and Business Updates and Third Quarter 2023 Financial Results
Demonstrated initial clinical validation of tumor-selective activation technology for both XTX101, a tumor-activated, Fc-enhanced anti-CTLA-4, and XTX202, a tumor-activated, beta-gamma IL-2
On track to activate trial sites for XTX101 dose escalation in combination with atezolizumab under clinical collaboration with Roche in the fourth quarter of 2023
Reported initial Phase 1/2 data for XTX202, including a 50% disease control rate at higher doses (≥2.8 mg/kg), and plans to evaluate XTX202 as monotherapy at 4.0 mg/kg in ongoing Phase 2 trial in patients with melanoma and renal cell carcinoma
Anticipate reporting preliminary Phase 1 safety data for XTX301, a tumor-activated, engineered IL-12, in the fourth quarter of 2023
WALTHAM, Mass., November 9, 2023 – Xilio Therapeutics, Inc. (Nasdaq: XLO), a clinical-stage biotechnology company discovering and developing tumor-activated immuno-oncology therapies for people living with cancer, today announced pipeline progress and business updates and reported financial results for the third quarter ended September 30, 2023.
“Colorectal cancer is the third largest solid tumor cancer in terms of number of patients diagnosed annually and the second leading cause of cancer-related deaths globally,” said René Russo, Pharm.D., president and chief executive officer of Xilio. “Rates of MSS colorectal cancer are rising in younger people, particularly in men under 50 years old, and patients often present with advanced Stage 4 disease along with liver metastases. Despite these alarming trends, there are few treatment options and no approved immunotherapies for these patients today. We believe the unique tumor-selective mechanism of XTX101 combined with atezolizumab has the potential to treat MSS colorectal cancer, and we are focused on initiating the co-funded collaboration with Roche to study this combination in patients. We are also encouraged by the recent Phase 1/2 data reported at SITC for XTX202 demonstrating a 50% disease control rate at higher doses (≥2.8 mg/kg), including patients with cold tumors, and a generally well-tolerated safety profile across all dose levels. We look forward to evaluating the 4 mg/kg dose for XTX202 in Phase 2 for patients with melanoma and renal cell carcinoma.”
Pipeline and Business Updates
XTX101: tumor-activated, Fc-enhanced anti-CTLA-4
XTX101 is an investigational tumor-activated, Fc-enhanced, high affinity binding anti-CTLA-4 designed to block CTLA-4 and deplete regulatory T cells when activated (unmasked) in the tumor microenvironment (TME). XTX101 is currently being evaluated at the recommended Phase 2 dose and schedule of 150 mg once every six weeks in monotherapy dose expansion of an ongoing Phase 1 clinical trial in patients with advanced solid tumors.
| ● | In the third quarter of 2023, Xilio reported updated data from the Phase 1 trial for XTX101, including an ongoing durable confirmed partial response through 36 weeks as of an August 3, 2023 data cutoff date in a patient with Stage 4 non-small cell lung cancer treated with XTX101 monotherapy, including resolution of liver metastases. |
| ● | Additionally, Xilio recently reported pharmacokinetic (PK) data showing activation of XTX101 in two on-treatment biopsies from patients in the Phase 1 trial, which included a primary melanoma tumor and a metastatic lesion in the liver from a patient with microsatellite stable colorectal cancer (MSS CRC). For both patients, XTX101 was more than 70% activated in the tumor while maintaining a peripheral activation level of 13%, consistent with the tumor-selective design for XTX101. |
| ● | In the third quarter of 2023, Xilio entered into a clinical trial collaboration with Roche to evaluate XTX101 in combination with atezolizumab in Phase 1 combination dose escalation in patients with advanced solid tumors and a planned Phase 2 trial in patients with MSS CRC. Xilio anticipates activating clinical trial sites for the Phase 1 combination dose escalation in the fourth quarter of 2023. |