Short-course pelvic radiotherapy with CAPOX chemotherapy plus QL1706 immunotherapy for rectal cancer that has spread to the liver

A Phase II Multicenter Clinical Trail of Efficacy and Safety of Short Course Radiotherapy Combined With CAPOX and PD-1/CTLA-4 Bispecific Antibody QL1706 in Patients With Liver Metastases From Rectal Cancer

This Phase 2 trial will test whether short-course radiotherapy combined with CAPOX chemotherapy and the QL1706 dual PD‑1/CTLA‑4 immunotherapy helps adults with rectal cancer that has liver metastases (MSS/pMMR).

Quick facts

• Phase: Phase 2
• Study type: Interventional
• Enrollment: 42 (estimated)
• Ages: 18 Years to 75 Years
• Sex: All
• Sponsor: Fujian Cancer Hospital (Government)
• Drugs / interventions: chemotherapy, immunotherapy
• Locations: 2 sites (Fuzhou, Fujian and 1 other locations)
• Trial ID: NCT06787183 on ClinicalTrials.gov

What this trial studies

This Phase 2 interventional trial gives patients short-course pelvic radiotherapy together with systemic CAPOX (capecitabine plus oxaliplatin) and QL1706, a bifunctional PD‑1/CTLA‑4 immune checkpoint inhibitor, to treat rectal cancer with synchronous liver metastases. Eligible adults (18–75 years) must have pathologically confirmed rectal cancer, MSS/pMMR tumors, a Karnofsky Performance Status ≥70, adequate organ function, and no prior anti-tumor or immunotherapy. The study will monitor tumor response, conversion to resectability of the primary tumor and liver metastases, and safety/tolerability of the combination. The trial is conducted at Fujian Cancer Hospital and Fuzhou First General Hospital in Fuzhou, Fujian, China.

Who should consider this trial

Good fit: Adults 18–75 with newly diagnosed, pathologically confirmed rectal cancer and liver metastases who are MSS/pMMR, have KPS ≥70, adequate organ function, and have not received prior chemotherapy or immunotherapy are ideal candidates.

Not a fit: Patients with signet‑ring cell histology, MSI‑high/dMMR tumors, prior systemic or immunotherapy, recent other malignancies, pregnant or breastfeeding women, or those with uncontrolled CNS/psychiatric conditions are unlikely to benefit or are excluded from this protocol.

Why it matters

Potential benefit: If successful, this combination could increase tumor shrinkage and convert more patients to potentially curative surgery by improving control of both the rectal primary and liver metastases.

How similar studies have performed: Combining radiotherapy with chemotherapy and immune checkpoint blockade is a promising but experimental approach: early-phase studies in several solid tumors have shown enhanced local and systemic responses in some patients, but MSS colorectal cancers have historically been less responsive to checkpoint inhibitors.

Eligibility criteria

Inclusion Criteria:

1. Age 18-75 years, any gender.
2. Pathologically confirmed rectal cancer with liver metastases (stage M1).
3. Karnofsky Performance Status ≥70.
4. Adequate organ function, no contraindications to radiotherapy, or immunotherapy.
5. Microsatellite/mismatch repair status MSS/pMMR.
6. No prior chemotherapy or any other anti-tumor treatment before inclusion.
7. No prior immunotherapy.
8. Ability to comply with the study protocol during the study period.
9. Signed written informed consent.

Exclusion Criteria:

1. Pregnant or lactating women.
2. Pathological diagnosis of signet ring cell carcinoma.
3. History of other malignancies within the past 5 years, except cured skin cancer and cervical carcinoma in situ.
4. Uncontrolled epilepsy, central nervous system disorders, or history of psychiatric disorders that, in the opinion of the investigator, may interfere with signing the informed consent form or affect patient compliance with oral medication.
5. Clinically significant (i.e., active) cardiac disease, such as symptomatic coronary artery disease, New York Heart Association (NYHA) Class II or greater congestive heart failure, or significant arrhythmias requiring drug intervention (see Appendix 12), or history of myocardial infarction within the past 12 months.
6. Organ transplant recipients requiring immunosuppressive therapy and long-term steroid users.
7. Patients with autoimmune diseases.
8. Severe uncontrolled recurrent infections or other severe uncontrolled comorbidities.
9. Subjects with baseline hematological and biochemical parameters not meeting the following criteria: hemoglobin ≥90g/L; absolute neutrophil count (ANC) .≥1.5×10\^9/L; platelets ≥100×10\^9/L; ALT, AST ≤2.5 times the upper limit of normal; ALP ≤2.5 times the upper limit of normal; serum total bilirubin \<1.5 times the upper limit of normal; serum creatinine \<1 times the upper limit of normal; serum albumin ≥30g/L.
10. Known deficiency of dihydropyrimidine dehydrogenase (DPD).
11. Allergy to any investigational drug components.

Where this trial is running

Fuzhou, Fujian and 1 other locations

• Fuzhou First General Hospital — Fuzhou, Fujian, China (Not_yet_recruiting)
• Fujian Cancer Hospital — Fuzhou, Fujian, China (Recruiting)

Study contacts

• Study coordinator: Hui Li, MD

Conditions Locally Advanced Rectal Cancer With Liver Metastases; short course radiotheraphy; CAPOX; QL1706