Involved-field Radiotherapy-TNT Combined With PD-1 Inhibitor for pMMR Locally Advanced Rectal Cancer (Neo-Field I)

Hebei Medical University

Status and phase: Enrolling; Phase 2

Conditions: Locally Advanced Rectal Cancer

Treatments: Drug: Capecitabine; Procedure: TME surgery; Radiation: Involve-field irradiation; Radiation: Elective nodal irradiation; Drug: CAPOX; Drug: Camrelizumab

Study type: Interventional

Funder types: Other

Identifiers

NCT07057089

ARK-Rectal cancer-001

Details and patient eligibility

About

The purpose of this study is to explore the efficacy and safety of involved-field radiotherapy-TNT combined with PD-1 inhibitors in pMMR locally advanced rectal cancer.

Enrollment: 162 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Age ≥18 years old, male or female;
2. Eastern Cooperative Oncology Group (ECOG) performance status of 0-1;
3. Pathologic diagnosis of adenocarcinoma of the rectum, definite pMMR type;
4. Clinical staging of T3-4NanyM0 or T1-2N+M0 (based on AJCC 8th edition staging criteria);
5. The lower margin of the primary tumor is located below the peritoneal reflex or the lower margin of the tumor is ≤10 cm from the anal verge;
6. Pre-enrollment laboratory indicators meet the following indicator ranges： 1)Blood: absolute neutrophils ≥1.5×10^9/L, platelets ≥100×10^9/L, hemoglobin ≥90g/L; 2)Liver and kidney function: ALT/AST ≤ 2.5 x ULN, total bilirubin ≤ 1.5 x ULN, creatinine ≤ 1.5 x ULN or creatinine clearance ≥ 60mL/min (Cockcroft-Gault formula)； 3)Coagulation: INR ≤ 1.5, APTT ≤ 1.5 x ULN (for those not receiving anticoagulation)；
7. Women or men of childbearing potential need to agree to use effective contraception during the study and for 6 months after the last treatment session;
8. Voluntary written informed consent and commitment to complete the full treatment and follow-up program.

Exclusion criteria

1. Pathologic type is other specific types such as neuroendocrine carcinoma, squamous carcinoma, etc;
2. Previous radiotherapy, chemotherapy, targeted or immunotherapy for rectal cancer;
3. Active autoimmune diseases (e.g., systemic lupus erythematosus, rheumatoid arthritis requiring long-term immunosuppressive therapy)；
4. Presence of active infection (e.g. HIV, HBV/HCV viral load positive requiring stabilization on antiretroviral therapy)；
5. Severe cardiovascular disease (e.g., myocardial infarction within 6 months, unstable angina, uncontrolled hypertension >160/100 mmHg)；
6. History of other malignant tumors (except non-melanoma skin cancers, cervical cancer in situ, etc. cured for ≥5 years)；
7. Uncontrolled diabetes mellitus (HbA1c > 8%), abnormal thyroid function (TSH outside normal range and requiring pharmacologic intervention)；
8. Severe chronic bowel disease (e.g., Crohn's disease, active ulcerative colitis)； Patients deemed by the investigator to be unsuitable for participation in this study.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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162 participants in 2 patient groups

Involve-field chemoradiotherapy-TNT+Camrelizumab

Experimental group

Description:

Patients received Involve-field long-course concurrent chemoradiotherapy (50.4 Gy/28f, including the primary rectal tumor, metastatic or suspected pelvic lymph nodes, mesorectal, and presacral regions). Capecitabine (825 mg/m² bid) was administered orally on radiotherapy days. At 30.6 Gy/17 fractions, patients received one cycle of Carilizumab (200 mg). Four cycles of CAPOX plus Carilizumab were given to patients 1-2 weeks after chemoradiotherapy completion. Patients were evaluated 2-3 weeks after the end of treatment. Patients who met the cCR criteria could choose to undergo surgical treatment or not. For patients who did not meet the cCR criteria, surgical treatment was recommended. For patients who refused surgery, the patients in the trial group continued to receive 4 cycles of CAPOX chemotherapy combined with camrelizumab.

Treatment:

Drug: Camrelizumab

Drug: CAPOX

Radiation: Involve-field irradiation

Procedure: TME surgery

Drug: Capecitabine

Elective nodal irradiation-TNT

Other group

Description:

Patients received elective nodal long-course concurrent chemoradiotherapy (50.4 Gy/28f). Capecitabine (825 mg/m² bid) was administered orally on radiotherapy days. Four cycles of CAPOX were given to patients 1-2 weeks after chemoradiotherapy completion. Patients were evaluated 2-3 weeks after the end of treatment. Patients who met the cCR criteria could choose to undergo surgical treatment or not. For patients who did not meet the cCR criteria, surgical treatment was recommended. For patients who refused surgery, the patients in the trial group continued to receive 4 cycles of CAPOX chemotherapy.

Treatment:

Radiation: Elective nodal irradiation

Drug: CAPOX

Procedure: TME surgery

Drug: Capecitabine