Modified SCRT Followed by Tislelizumab Plus CAPOX for Locally Advanced Rectal Cancer

A Phase II Multicenter Clinical Trial of Modified Short-course Radiotherapy Combined With CAPOX and PD-1 Monoclonal Antibody for Locally Advanced Mid-low Rectal Cancer

To explore the complete response (CR) rate of modified short-course radiotherapy combined with CAPOX and tislelizumab for locally Advanced Mid-low Rectal Cancer

Study Overview

• Status: Completed
• Conditions: Mid-low Rectal Cancer
• Intervention / Treatment: Drug: Tislelizumab; Radiation: Short-course Radiotherapy; Drug: Capecitabine; Drug: Oxaliplatin

Detailed Description

In the neoadjuvant treatment of rectal cancer, the new mode of short-course radiotherapy and chemotherapy combined with immunotherapy has shown good potential for application. Combining PD-1 antibody with short-course radiotherapy and chemotherapy to increase the tumour-killing and immune-mediated effects of the radiation dose may further improve tumour regression and increase the complete remission rate, providing a promising treatment option for patients with low-grade rectal cancer who are seeking a 'wait-and-see' strategy to preserve organ function.

• Study Type: Interventional
• Enrollment (Actual): 38
• Phase: Phase 2

Contacts and Locations

Study Locations

• China
  • Fujian
    • Fuzhou, Fujian, China, 350014
      • Fujian Cancer Hospital
    • Longyan, Fujian, China, 364000
      • The Second Hospital of Longyan
    • Quanzhou, Fujian, China, 362200
      • Jinjiang Municipal Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age 18-75 years, any gender.
• Pathologically confirmed rectal adenocarcinoma.
• Baseline MR stage T3-4/N+.
• Distance from anal verge ≤12cm.
• No distant metastasis.
• Karnofsky Performance Status ≥70.
• Adequate organ function, no contraindications to surgery, radiotherapy, or immunotherapy.
• Microsatellite/mismatch repair status MSS/pMMR.
• No prior chemotherapy or any other anti-tumor treatment before inclusion.
• No prior immunotherapy.
• Ability to comply with the study protocol during the study period.
• Signed written informed consent.

Exclusion Criteria:

• Pregnant or lactating women.
• Pathological diagnosis of signet ring cell carcinoma.
• History of other malignancies within the past 5 years, except cured skin cancer and cervical carcinoma in situ.
• 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.
• 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.
• Organ transplant recipients requiring immunosuppressive therapy and long-term steroid users.
• Patients with autoimmune diseases.
• Severe uncontrolled recurrent infections or other severe uncontrolled comorbidities.
• 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.
• Known deficiency of dihydropyrimidine dehydrogenase (DPD).
• Allergy to any investigational drug components.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Modified Short-course Radiotherapy Combined with CAPOX and Tislelizumab; Modified SCRT (GTV 30Gy/5f, CTV 22.5Gy/5f), followed by Tislelizumab and CAPOX q3w *2 cycles. Efficacy and surgery were assessed 2-4 weeks after the end of treatment.	Drug: Tislelizumab; Tislelizumab：200mg，d1，q3w，2 cycles.; Radiation: Short-course Radiotherapy; Rectal lesion + metastatic lymph nodes, GTV 30Gy/5Fx. Pelvic lymphatic drainage area, CTV 22.5Gy/5Fx.; Drug: Capecitabine; Capecitabine：1000mg/m2，d1-14，bid, q3w, 2 cycles.; Drug: Oxaliplatin; Oxaliplatin：130mg/m2, d1, q3w, 2 cycles

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Complete response (CR) rate	Including pCR and CCR.	From enrollment to 3 month and during follow-up

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
3y-DFS		From enrollment to 36 month
Organ preservation rate	Sphincter-saving rate in enrolled patients	1 year.
3-year OS	The percentage of patients enrolled who are still alive three years after their initial enrollment.	From enrollment to 36 month
Quality of life	EORTC Core Quality of Life questionnaire (QLQ-C30)，range from 0-100, with comprehensive assessment indicators, including positive and negative indicators.	Before each treatment, before surgery and during follow-up.

Collaborators and Investigators

• Sponsor: Fujian Cancer Hospital

Study record dates

Study Major Dates

• Study Start (Actual): July 12, 2024
• Primary Completion (Actual): August 10, 2025
• Study Completion (Actual): August 14, 2025

Study Registration Dates

• First Submitted: March 20, 2024
• First Submitted That Met QC Criteria: March 20, 2024
• First Posted (Actual): March 27, 2024

Study Record Updates

• Last Update Posted (Estimated): August 15, 2025
• Last Update Submitted That Met QC Criteria: August 14, 2025
• Last Verified: August 1, 2025

More Information

Terms related to this study

• Keywords: CAPOX; short-course radiotherapy; PD-1 monoclonal antibody
• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Intestinal Diseases; Gastrointestinal Neoplasms; Digestive System Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Colorectal Neoplasms; Intestinal Neoplasms; Rectal Diseases; Rectal Neoplasms; Antineoplastic Agents, Immunological; Antineoplastic Agents; Molecular Mechanisms of Pharmacological Action; Antimetabolites, Antineoplastic; Antimetabolites; Capecitabine; Oxaliplatin; Tislelizumab
• Other Study ID Numbers: CATIMOR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No