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Withdrawn Phase 2 Interventional

Immunotherapies in Combination With Stereotactic Body Radiation Radiotherapy in Microsatellite Stable (MSS) Metastatic Colorectal Cancer (mCRC)

ClinicalTrials.gov ID: NCT06603818

Public ClinicalTrials.gov record NCT06603818. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Sep 11, 2026, 12:21 PM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Official title

A Phase II Study of Immunotherapies (Tiragolumab and Atezolizumab) in Combination With Stereotactic Body Radiation Radiotherapy in Microsatellite Stable (MSS) Metastatic Colorectal Cancer (mCRC)

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

Background: Metastatic colorectal cancer (mCRC) is cancer that has spread beyond the colon and rectum. Most people with mCRC die within 5 years. New immune-based treatments are making progress with some types of colon cancer. But these treatments do little for people with a type of cancer that is microsatellite stable (MSS). MSS is a specific cancer biomarker. Better treatments are needed. Objective: To test 2 drugs (tiragolumab and atezolizumab) combined with radiation therapy in people with MSS mCRC. Eligibility: People aged 18 years and older with MSS mCRC. Design: Participants will be screened. They will have a physical exam with blood tests. They will have imaging scans and a test of their heart function. They will provide a tissue sample from their tumor; if one is not already available, a new sample will be taken. Their ability to perform normal tasks will be assessed. Tiragolumab and atezolizumab are both administered through a tube attached to a needle inserted into a vein. Participants will receive both drugs on day 1 of 3-week treatment cycles. Each study visit should last about 8 hours. Participants will receive radiation therapy on days 1, 3, and 5 of cycle 1 only. Blood samples and rectal swabs will be collected on day 1 of every cycle. Imaging scans will be repeated every 9 weeks. Additional tumor samples may be taken during treatment. Treatment will continue for up to 2 years. Participants will have a follow-up visit 1 month after treatment ends. Follow-up visits will continue every 3 months for 1 more year.

Study identification

NCT ID
NCT06603818
Recruitment status
Withdrawn
Study type
Interventional
Phase
Phase 2
Enrollment
Not listed

Conditions and interventions

Eligibility (public fields only)

Age range
18 Years to 120 Years
Sex
All
Healthy volunteers
Healthy volunteers not accepted

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Aug 14, 2025
Primary completion
Aug 14, 2025
Completion
Aug 14, 2025
Last update posted
Feb 18, 2026

2025

United States locations

U.S. sites
1
U.S. states
1
U.S. cities
1
Facility City State ZIP Site status
National Institutes of Health Clinical Center Bethesda Maryland 20892

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT06603818, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Feb 18, 2026 · Synced Sep 11, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT06603818 live on ClinicalTrials.gov.

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