Clinical trial Recruiting at 5 sites Phase 2 Interventional Ages 18 to 75

Comparing long-course chemoradiation versus short-course radiation plus CAPOX, a PD-1 blocker (serplulimab), and celecoxib for locally advanced rectal cancer

Official title: A Randomized Phase II Study of Long-term Chemoradiotherapy or Short-term Radiotherapy Combined With CAPOX, PD-1 Monoclonal Antibody and COX-2 Inhibitors in MSS Type Locally Advanced Rectal Cancer

Run by Fudan University · NCT07154316 · Data updated 2026-11-12

This trial will test whether adding CAPOX, the PD-1 drug serplulimab, and celecoxib to short-course radiotherapy works better than standard long-course chemoradiation for adults with MSS locally advanced rectal cancer.

Quick facts

PhasePhase 2
Study typeInterventional
Ages18 Years to 75 Years
SexAll
Enrollment138 (estimated)
SponsorFudan University
Academic / other
Drugs / interventionschemotherapy, immunotherapy, serplulimab
Locations5 sites (Fuzhou, Fujian and 4 other locations)
StatusRecruiting
StartedAugust 1, 2025
Main results expectedAugust 1, 2028
Study endsDecember 30, 2028
Registry record updatedSeptember 4, 2025
Trial IDNCT07154316 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Ideal candidates are adults age 18–75 with pathologically confirmed MSS/pMMR locally advanced rectal adenocarcinoma (T3-4 and/or N+, tumor ≤10 cm from anal verge), no distant metastasis, KPS ≥70, and no prior chemotherapy or immunotherapy.

Probably not a fit

Patients with MSI-high/dMMR tumors, distant metastases, prior systemic therapy, poor performance status, pregnancy, or serious uncontrolled comorbidities are unlikely to benefit or are ineligible for this protocol.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This randomized phase II trial enrolls adults with microsatellite-stable (MSS) locally advanced rectal adenocarcinoma to compare standard long-course chemoradiotherapy (50 Gy in 25 fractions with capecitabine) against short-course radiotherapy (25 Gy in 5 fractions) followed by CAPOX (capecitabine plus oxaliplatin), the PD-1 inhibitor serplulimab, and the COX-2 inhibitor celecoxib. The primary endpoint is combined complete response rate (pathologic complete response plus clinical complete response), with secondary endpoints including anal-preservation rate and three-year survival outcomes. The protocol also includes correlative studies to explore how the triple regimen alters the tumor microenvironment and immune response. Participants must be treatment-naïve for chemotherapy and immunotherapy and have tumors located ≤10 cm from the anal verge.

Why it matters

Potential benefit: If successful, the combination approach could raise complete remission rates and increase the chance of preserving the anus while reducing recurrence.

How similar studies have gone: Short-course radiotherapy combined with chemotherapy and PD-1 blockade has shown encouraging early signals in rectal cancer, but adding a COX-2 inhibitor like celecoxib is a novel component that remains exploratory.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Age 18-75 years, regardless of gender.
* Pathologically confirmed rectal adenocarcinoma.
* Tumor located ≤10 cm from the anal verge.
* Baseline stage T3-4 and/or N+ (locally advanced disease).
* No evidence of distant metastasis.
* Microsatellite stability (MSS) or proficient mismatch repair (pMMR).
* Karnofsky Performance Status (KPS) ≥70.
* No prior chemotherapy or any other anticancer therapy before enrollment.
* No prior immunotherapy.
* Able to comply with study protocol requirements throughout the study period.
* Signed written informed consent obtained prior to study participation.

Exclusion Criteria:

* Pregnant or lactating women.
* Individuals with a history of other malignant diseases within the past 5 years, excluding cured skin cancer and cervical carcinoma in situ.
* Individuals with a history of uncontrolled epilepsy, central nervous system diseases, or mental disorders, where the clinical severity (as judged by the investigator) may impair the ability to sign the informed consent form or affect compliance with oral medication.
* Clinically significant (i.e., active) heart disease, including symptomatic coronary heart disease, congestive heart failure of New York Heart Association (NYHA) class II or worse, severe arrhythmias requiring pharmacological intervention, or a history of myocardial infarction within the past 12 months.
* Individuals requiring immunosuppressive therapy for organ transplantation and those on long-term corticosteroid therapy.
* Individuals with autoimmune diseases.
* Individuals with severe, uncontrolled, recurrent infections or other severe, uncontrolled concurrent diseases.
* Baseline blood routine and biochemical parameters not meeting the following criteria: hemoglobin ≥90 g/L; absolute neutrophil count (ANC) ≥1.5×10⁹/L; platelets ≥100×10⁹/L; alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤2.5× upper limit of normal (ULN); alkaline phosphatase (ALP) ≤2.5×ULN; serum total bilirubin \<1.5×ULN; serum creatinine \<1×ULN; serum albumin ≥30 g/L.
* Individuals with known dihydropyrimidine dehydrogenase (DPD) deficiency. Individuals with a history of hypersensitivity to any component of the study medications.

Where it's running

  • Fujian Provincial Cancer Hospital
    Fuzhou, Fujian, China
    Recruiting
  • Anyang Tumor Hospital
    Anyang, Henan, China
    Recruiting
  • The First Affiliated Hospital of Shandong First Medical University
    Jinan, Shandong, China
    Recruiting
  • Yunnan Cancer Hospital
    Kunming, China
    Recruiting
  • Fudan University Shanghai Cancer Center
    Shanghai, China
    Recruiting

Study contacts

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.