Neoadjuvant Moderately Hypofractionated Radiotherapy Combined With Chemotherapy and Immunotherapy for High-risk pMMR/MSS Locally Advanced Rectal Cancer: A Prospective, Multi-center Randomized Control Phase II Trial

Trial statusNot yet recruiting
Trial phasePhase 2
Trial typeInterventional
Biological sexAll
Age18-75
SponsorFudan University

About this trial

This study aims to observe and evaluate the efficacy and safety of moderately hypofractionated radiotherapy combined with chemotherapy and immunotherapy, compared with conventional neoadjuvant chemoradiotherapy, in patients with high-risk locally advanced colorectal cancer.

Eligibility criteria

This trial does not accept healthy volunteers

Qualifiers

Age ≥ 18 years and ≤ 75 years.

Histologically confirmed colorectal adenocarcinoma with the lower margin of the lesion ≤ 10 cm from the anal verge as assessed by MRI, and immunohistochemistry confirming pMMR, or genetic testing demonstrating MSI-L or MSS.

Presence of at least one of the following high-risk factors as assessed by pelvic MRI: cT4a/b; N2; extramural vascular invasion (EMVI+); mesorectal fascia involvement (MRF+); enlarged lateral lymph node (longest diameter > 7 mm).

Eastern Cooperative Oncology Group (ECOG) performance status score of 0-1

Disqualifiers

Presence of distant metastasis.

Patients with stage I or II rectal cancer who do not require preoperative neoadjuvant therapy.

Severe diseases involving the heart, lung, brain, kidney, gastrointestinal tract, or other systemic conditions.

Untreated chronic hepatitis B or HBV carriers with HBV DNA > 500 IU/mL, or patients positive for HCV RNA. Patients with inactive hepatitis B surface antigen (HBsAg) carriers, those with hepatitis B who have been treated and are stable (HBV DNA < 500 IU/mL), and those who have been cured of hepatitis C may be enrolled.

Trial design

Design model

Parallel

Treatments tested in this trial

  • Moderately Hypofractionated Radiotherapy

    Radiation

    CapOx Regimen Recommended Dose:Capecitabine: 1000 mg/m² orally twice daily on days 1-14 of each 21-day cycle.Oxaliplatin: 130 mg/m² intravenously on day 1 of each 21-day cycle. Serplulimab: 300 mg intravenously on day 1 of each 21-day cycle. Moderately Hypofractionated Radiotherapy:Delivered using a simultaneous integrated boost (SIB) technique.Gross tumor volume (GTV): 3.5 Gy per fraction; clinical target volume (CTV): 3.0 Gy per fraction.Once daily, 5 fractions per week, for a total of 10 fractions.Total dose: GTV 35 Gy, CTV 30 Gy.

  • Serplulimab

    Drug

    CapOx Regimen Recommended Dose:Capecitabine: 1000 mg/m² orally twice daily on days 1-14 of each 21-day cycle.Oxaliplatin: 130 mg/m² intravenously on day 1 of each 21-day cycle. Serplulimab: 300 mg intravenously on day 1 of each 21-day cycle. Long-course Concurrent Chemoradiotherapy:Delivered using a conventional fractionation schedule.Gross tumor volume (GTV): 1.8-2.0 Gy per fraction, total dose 50-50.4 Gy.Clinical target volume (CTV): 1.8 Gy per fraction, total dose 45 Gy.Once daily, 5 fractions per week.GTV receives 25-28 fractions; CTV receives 25 fractions.

  • CapOx+Long-course radiotherapy

    Other intervention

    CapOx Regimen Recommended Dose:Capecitabine: 1000 mg/m² orally twice daily on days 1-14 of each 21-day cycle.Oxaliplatin: 130 mg/m² intravenously on day 1 of each 21-day cycle. Long-course Concurrent Chemoradiotherapy:Delivered using a conventional fractionation schedule.Gross tumor volume (GTV): 1.8-2.0 Gy per fraction, total dose 50-50.4 Gy.Clinical target volume (CTV): 1.8 Gy per fraction, total dose 45 Gy.Once daily, 5 fractions per week.GTV receives 25-28 fractions; CTV receives 25 fractions.

Treatment groups

165 Participants
are divided into 3 treatment groups
Group A: Experimental group AExperimental treatment 1 intervention
Group B: Experimental group BExperimental treatment 1 intervention
Group C: Control armActive comparator 1 intervention

Trial outcomes

Primary outcomes

1

Complete Remission (CR) Rate

Definition: The proportion of participants achieving complete remission, defined as: Pathologic complete response (pCR): No residual viable tumor cells detected in the resected specimen after neoadjuvant treatment (ypT0N0) Sustained clinical complete response (cCR): No evidence of residual tumor on digital rectal examination, endoscopy, and MRI, maintained for more than 1 year without surgery Assessment Method: Evaluated by investigators based on imaging, endoscopic findings, pathology (for surgical cases), and clinical examination

Time frame
At the time of surgery for pCR, and at 1 year after achieving cCR for sustained cCR

Secondary outcomes

1

3-Year Disease-Free Survival (DFS) Rate

Time from randomization to evidence of disease recurrence within 3 years

Time frame
Up to 3 years after randomization
2

3-Year Overall Survival (OS) Rate

Time from randomization to death from any cause.

Time frame
up to 5 years
3

3-Year Event-Free Survival (EFS) Rate

Defined as the time from the start of treatment to the occurrence of any of the following events, whichever occurs first: disease progression that precludes surgery, postoperative disease progression or recurrence (per RECIST v1.1), or death from any cause.

Time frame
up to 3 years from treatment
4

Objective Response Rate

The rate of participants that achieve either a complete response (CR) or a partial response (PR).

Time frame
Up to 1 years

Other outcomes

1

Quality of life (QoL)

Quality of life will be evaluated using the European O-rganization for Reasearch and Treatment of Cancer Quality of Life Questionnaire-C30(EORTC QLQ-C30) (range 0-100). It evaluates the quality of life from 30 aspects, including appetite, mental status, sleep quality, fatigue, etc. The higher scores mean a better quality of life.

Time frame
From date of randomization until the date of death from any cause, assessed up to 10 years

Sponsors and contacts

Click on the lead sponsor to view all of their trials.

This trial is not recruiting at the moment. You can still explore other options: