New drug combo takes on tough cancers in early trial

NCT ID NCT04896697

Completed Disease control Sponsor: Xilio Development, Inc. Source: ClinicalTrials.gov ↗

First seen Jun 26, 2026 · Last updated Jun 27, 2026 · Updated 1 time

Summary

This early-phase trial tested a new drug called vilastobart, alone or with another drug (atezolizumab), in 125 people with advanced solid tumors that had stopped responding to standard treatments. The main goals were to check safety and find the right dose. Researchers also looked for signs that the tumors shrank.

What this could mean

Our plain-language read of the trial. This is informational only — not medical advice or a prediction.

Active substance: vilastobart (XTX101) and atezolizumab
What this could lead to: If successful, this could point toward a new treatment option for advanced solid tumors that have not responded to standard therapies.
What could go wrong: This is a very early first-in-human trial, so safety and effectiveness are not yet proven. The small size and early phase mean results may not lead to a widely available treatment.

This is an AI summary of the original study and may miss details. Read our disclaimer.

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Conditions

The condition(s) this trial relates to.

colorectal cancer metastatic prostate carcinoma neoplasm small cell lung carcinoma

As listed by the trial registrant

The condition terms exactly as the trial's registrant entered them.

ADVANCED SOLID TUMOR

Contacts and locations

Locations

California Cancer Associates for Research and Excellence, cCARE

Encinitas, California, 92024, United States
California Cancer Associates for Research and Excellence, cCARE

San Marcos, California, 92069, United States
Carolina BioOncology Institute

Huntersville, North Carolina, 28078, United States
City of Hope

Duarte, California, 91010, United States
City of Hope-Lennar

Irvine, California, 92618, United States
City of Hope-Upland

Upland, California, 91786, United States
Duke University Medical Center

Durham, North Carolina, 27710, United States
Mary Crowley Cancer Research

Dallas, Texas, 75230, United States
Massachusetts General Hospital

Boston, Massachusetts, 02114, United States
Mayo Clinic Hospital

Phoenix, Arizona, 85054, United States
Mayo Clinic Hospital

Jacksonville, Florida, 32224, United States
Mayo Clinic Hospital

Rochester, Minnesota, 55905, United States
NEXT Virginia

Fairfax, Virginia, 22031, United States
Next Oncology

Austin, Texas, 78758, United States
Sarah Cannon Research Institute at Florida Cancer Specialists

Orlando, Florida, 32827, United States
Tranquil Clinical Research

Webster, Texas, 77598, United States
UCLA Hematology/Oncology- Santa Monica

Santa Monica, California, 90404, United States
USC/Norris Comprehensive Cancer Center

Los Angeles, California, 90033, United States
University of Pittsburgh Medical Center- Hillman Cancer Center

Pittsburgh, Pennsylvania, 15232, United States

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