Xilio Therapeutics, Inc. announced additional data from its Phase 2 clinical trial evaluating XTX202, a tumor-activated, beta-gamma biased IL-2, in patients with metastatic renal cell carcinoma (RCC) or unresectable or metastatic melanoma. As of a data cutoff date of March 6, 2024: A total of 17 RCC patients and 20 melanoma patients were administered XTX202 in the Phase 2 trial in an outpatient setting at dose levels of 1.4 mg/kg once every three weeks (Q3W) or 4 mg/kg Q3W. In 26 patients evaluable for anti-tumor activity at both dose levels, stable disease (SD) continued to be the best response.

Investigators reported SD of at least nine-weeks duration in 7 RCC patients (70% disease control rate) and in 9 melanoma patients (56% disease control rate). In addition, XTX202 continued to be generally well-tolerated with safety data consistent with previously reported results. Xilio plans to present the full data set at a future medical meeting.

Together with previously reported data, Xilio believes these additional data further validate the company?s tumor-activated approach and support the broad potential for XTX202 as a combination therapy. Xilio plans to explore strategic opportunities to continue to develop XTX202 in combination with other agents.