Actively Recruiting
Efficacy and Safety of Combining Intestinal Low Dose Radiotherapy and PD-1/PD-L1 Inhibitors for Metastatic Malignant Solid Tumors After Acquired Resistance to Anti-PD1/PD-L1 Treatment
Led by Chuangzhen Chen · Updated on 2025-11-20
48
Participants Needed
1
Research Sites
N/A
Total Duration
On this page
AI-Summary
What this Trial Is About
Researchers are evaluating the combination of intestinal low-dose radiotherapy (ILDR) with PD-1/PD-L1 monoclonal antibody therapy in patients who have metastatic solid tumors that have become resistant to prior immune checkpoint blockade (ICB) treatments. This phase II clinical trial aims to understand the clinical benefit and safety of this combined approach across three groups based on tumor type: lung cancer, esophageal cancer, and other solid tumors. The study is motivated by evidence suggesting ILDR may enhance immune responses by affecting the gut environment, potentially improving immunotherapy effectiveness. All participants receive a single 1 Gy dose of radiotherapy targeting the jejunum and ileum, followed within 24 hours by PD-1/PD-L1 antibody treatment administered every three weeks. Patients continue maintenance therapy for up to two years. The trial includes three parallel cohorts with 16 patients each, focusing on different tumor types, and assesses treatment responses and safety based on established criteria. Tissue, stool, and blood samples are collected before and after treatment for advanced analyses to explore how the gut microbiota and immune system interact. Participants undergo regular evaluations including scans to measure tumor response, assessments of side effects, and immune and microbiota studies at multiple time points up to 48 weeks. Primary outcomes include objective and disease control response rates, progression-free survival, and observation of abscopal effects at 6, 12, and 24 weeks. Secondary outcomes focus on overall survival, cancer-specific survival, and adverse events. This comprehensive monitoring aims to clarify how ILDR influences immunotherapy resistance and identify markers linked to treatment outcomes.
CONDITIONS
Brief Title
Intestinal Low Dose Radiotherapy Combined With Immunotherapy in Immune-resistant Metastatic Malignant Solid Tumors
Who Can Participate
Eligibility Criteria
You may qualify if you...
- Age 18 years or older and up to 80 years, any gender
- ECOG performance status level between 0 and 2
- Expected life span longer than 3 months
- At least one accessible and measurable lesion according to RECIST criteria
- Diagnosed with metastatic solid tumors that have progressed after prior immunotherapy treatments
- Not eligible for surgical treatment
- Brain metastases clinically stable after treatment as confirmed by CT or MRI
- Complete clinical and pathological information available
- Able to understand and voluntarily sign informed consent
- No psychological, social, or geographical issues preventing compliance with the study
- Other general criteria appropriate for clinical trial participation
You will not qualify if you...
- Contraindications to radiation therapy or immunotherapy
- History of severe immune-related toxic side effects (such as immune myocarditis or pneumonia)
- Assessed with hyperprogressive disease
- Received pelvic or abdominal radiation therapy within 6 months before enrollment
- Previous treatment adverse reactions not recovered to CTCAE 5.0 grade 1 or less (except fatigue or hair loss)
- Active uncontrolled systemic infections despite treatment
- Significant liver or kidney dysfunction (lab values more than 3 times normal limits)
- Active hepatitis B, hepatitis C, HIV, or syphilis infections
- Brain disorders, symptomatic central nervous system or meningeal metastases, or impaired cognition
- Allergy to any study drugs
- History of drug or alcohol abuse
- Pregnant or breastfeeding women
- Participation in another therapeutic clinical trial
- Poorly controlled pleural, pericardial effusions or ascites requiring frequent drainage
- Major surgery within 30 days
- Use of antibiotics, antifungals, antivirals, antiparasitic agents, or probiotics within 4 weeks prior to enrollment
AI-Screening
AI-Powered Screening
Complete this quick 3-step screening to check your eligibility
Your Study Journey
Duration - 2 to 4 weeks
Participants are screened for eligibility to participate in the trial.
Duration - Up to 24 weeks
Participants receive a single low-dose radiotherapy targeting the intestine combined with PD-1/PD-L1 monoclonal antibody immunotherapy given at 3-week intervals.
Visits every 3 weeks for immunotherapy administration
Duration - Up to 48 weeks after radiotherapy initiation
Participants are monitored for overall survival, cancer-specific survival, and adverse events after completion of treatment.
Visits at 12, 24, and 48 weeks after radiotherapy
Trial Site Locations
Total: 1 location
1
Cancer Hospital, Shantou University Medical College
Shantou, Guangdong, China, 515031
Actively Recruiting
Research Team
C
Chuangzhen Chen, MD
How is the study designed?
Study Type
INTERVENTIONAL
Masking
NONE
Allocation
NON_RANDOMIZED
Model
PARALLEL
Primary Purpose
TREATMENT
Number of Arms
3
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