Cetuximab and Envafolimab Plus mFOLFOXIRI as First-line Treatment for RAS/BRAF Wild-type, MSS, Unresectable Left-side Metastatic Colorectal Cancer (CEIL)

Cetuximab and Envafolimab Plus mFOLFOXIRI Versus Cetuximab Plus mFOLFOX6 as First-line Treatment for RAS/BRAF Wild-type, MSS, Unresectable Left-side Metastatic Colorectal Cancer: A Randomized Controlled Phase II Trial (CEIL)

The primary aim of phase II CEIL study is to evaluate the efficacy of cetuximab and envafolimab plus mFOLFOXIRI versus cetuximab plus mFOLFOX6 as first line treatment of patients with initially unresectable and previously untreated RAS/BRAF wild-type, MSS, left-side metastatic colorectal cancer(mCRC), in terms of Progression-free Survival.

Study Overview

• Status: Recruiting
• Conditions: Metastatic Colorectal Cancer
• Intervention / Treatment: Drug: Cetuximab + Envafolimab + mFOLFOXIRI; Drug: Cetuximab + mFOLFOX6

Detailed Description

This is a prospective, open-label, multi-center, randomized controlled phase II trial in which patients with initially unresectable and previously untreated RAS/BRAF wild-type, MSS, left-side mCRC will be randomized to two therapy groups:

Experimental arm A: receive induction treatment with cetuximab and envafolimab plus mFOLFOXIRI up to 8 cycles followed by maintenance with cetuximab and envafolimab plus 5-FU/LV until disease progression, unacceptable toxicity or patient's refusal.

Standard arm B: receive induction treatment with cetuximab plus mFOLFOX6 up to 8 cycles followed by maintenance with cetuximab plus 5-FU/LV until disease progression, unacceptable toxicity or patient's refusal.

The second- and subsequent lines of treatment will be at investigators' choice.

• Study Type: Interventional
• Enrollment (Estimated): 198
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Yanhong Deng, Ph.D; Phone Number: 86-13925106525; Email: 13925106525@163.com
• Study Contact Backup: Name: Xiaoyu Xie, M.D.; Phone Number: 86-13570487315; Email: xie_xyu@163.com

Study Locations

• China
  • Guangdong
    • Foshan, Guangdong, China, 528000
      • Recruiting
      • The First People's Hospital of Foshan
      • Contact: Wei Wang, Ph.D; Phone Number: 8618666392971
    • Guangzhou, Guangdong, China, 510655
      • Recruiting
      • The Sixth Affiliated Hospital of Sun Yat-sen University
      • Contact: Yanhong Deng, Ph.D; Phone Number: 8613925106525; Email: dengyanh@mail.sysu.edu.cn
  • Guizhou
    • Guiyang, Guizhou, China, 550000
      • Recruiting
      • Affiliated Cancer Hospital of Guizhou Medical University
      • Contact: Wen-Ling Wang, Ph.D; Phone Number: 8613885077539

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Signed informed consent obtained before any study specific procedures. Subjects must be able to understand and willing to sign a written informed consent.
• Male or female subjects ≥ 18 years, expected lifespan ≥ 12 weeks.
• Patients have histologically or cytologically confirmed RAS and BRAF wild-type, MSS metastatic colorectal adenocarcinoma (mCRC), excluding appendiceal and anal cancers.
• AJCC/UICC stage IV left-side metastatic colorectal cancer. At least one measurable lesion according to RECIST 1.1.
• The patient has not previously received any systemic treatment specifically targeting advanced or metastatic colorectal cancer, including chemotherapy, monoclonal antibodies such as cetuximab or panitumumab targeting the epidermal growth factor receptor (EGFR), bevacizumab targeting the vascular endothelial growth factor (VEGF), immune checkpoint inhibitors such as anti-PD-1 or anti-PD-L1 antibodies, and anti-CTLA-4 antibodies. If recurrence or metastasis occurs during or within 6 months after adjuvant or neoadjuvant chemotherapy, adjuvant/neoadjuvant therapy is considered as a first-line systemic treatment for advanced or metastatic disease.
• Eastern Cooperative Oncology Group (ECOG) performance status of 0-1.
• Within 7 days before treatment, the following laboratory test values are obtained and appropriate organ function is present:

Hemoglobin ≥ 90g/L, neutrophil count ≥ 1.5 × 10^9/L, platelet count ≥ 75 × 10^9/L; Serum total bilirubin ≤ 1.5 × upper limit of normal (UNL); Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) ≤ 2.5 × UNL; if there are liver metastases, AST or ALT ≤ 5 × UNL; Serum creatinine ≤ 1.5 × UNL.

• Women of childbearing potential must have a negative blood pregnancy test at the baseline visit. For this trial, women of childbearing potential are defined as all women after puberty, unless they are postmenopausal for at least 12 continuous months, are surgically sterile, or are sexually inactive.
• Patients are not allowed to participate in other clinical trials during the study period and willing to comply with the study protocol and visit plan.

Exclusion Criteria:

• Concurrent active malignancy, excluding malignancies with disease-free survival of 5 years or more or in situ carcinoma considered cured after adequate treatment.
• Currently diagnosed with gastrointestinal diseases such as duodenal ulcer, ulcerative colitis, intestinal obstruction, or other conditions determined by the investigator to potentially cause gastrointestinal bleeding or perforation.
• Experienced thrombotic or embolic events, such as cerebrovascular accidents (including transient ischemic attacks), pulmonary embolism, or deep vein thrombosis, within the 12 months prior to study enrollment.
• Experienced the following conditions within the 12 months prior to study enrollment: myocardial infarction, severe/unstable angina pectoris, New York Heart Association (NYHA) class II or above heart failure, clinically significant supraventricular or ventricular arrhythmias, or symptomatic congestive heart failure.
• Use of systemic antibiotics for ≥7 days within the 4 weeks prior to study enrollment, or the occurrence of unexplained fever (>38.5°C) during the screening period/prior to the first dose (fever attributed to the tumor can be considered for enrollment, as determined by the investigator).
• Presence of uncontrolled pleural effusion, ascites, or pericardial effusion within 14 days prior to study enrollment despite appropriate treatment.
• Presence of any unresolved adverse events of Grade 2 or higher (excluding anemia, alopecia, and skin pigmentation) attributed to previous treatments according to the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) version 5.0.
• Presence of interstitial lung disease, non-infectious pneumonia, or uncontrolled systemic diseases (e.g., diabetes, hypertension, pulmonary fibrosis, and acute pneumonia).
• Known human immunodeficiency virus (HIV) infection or known active hepatitis (defined as HBV-DNA ≥ 500 IU/ml for hepatitis B, and HCV-RNA above the limit of detection for hepatitis C) or co-infection with hepatitis B and C.
• History of known or suspected allergy to any investigational drug used in the study.
• Pregnancy or lactation in women.
• Pre-menopausal women (last menstrual period <2 years ago) who do not use or refuse to use effective non-hormonal contraception, or fertile men.
• Presence of other significant physical or mental illnesses or laboratory abnormalities that may increase the risk of participation in the study, interfere with study results, or are deemed unsuitable for participation by the investigator.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Arm A; cetuximab+envafolimab+mFOLFOXIRI up to 8 cycles followed by maintenance with cetuximab+envafolimab+5-FU/LV	Drug: Cetuximab + Envafolimab + mFOLFOXIRI; Cetuximab 500mg/m² + envafolimab 200mg + irinotecan 150 mg/m² + oxaliplatin 85 mg/m² + leucovorin 200 mg/m² + 5-FU 2400 mg/m² civ. 46h all on day 1 of each 2 weeks cycle up to max 8 cycles, followed by maintenance with cetuximab 500mg/m² + envafolimab 200mg + leucovorin 200 mg/m² + 5-FU 400 mg/m² + 5-FU 2400 mg/m² civ. 46h all on day 1 of each 2 weeks cycle until PD, unacceptable toxicity or patient's refusal.; Other Names: 5-FU; Leucovorin; Irinotecan; Oxaliplatin; Envafolimab; Cetuximab or c225
Active Comparator: Arm B; cetuximab+mFOLFOX6 up to 8 cycles followed by maintenance with cetuximab+5-FU/LV	Drug: Cetuximab + mFOLFOX6; Cetuximab 500mg/m² + oxaliplatin 85 mg/m² + leucovorin 200 mg/m² + 5-FU 400 mg/m² + 5-FU 2400 mg/m² civ. 46h all on day 1 of each 2 weeks cycle up to max 8 cycles, followed by maintenance with cetuximab 500mg/m² + leucovorin 200 mg/m² + 5-FU 400 mg/m² + 5-FU 2400 mg/m² civ. 46h all on day 1 of each 2 weeks cycle until PD, unacceptable toxicity or patient's refusal.; Other Names: 5-FU; Leucovorin; Oxaliplatin; Cetuximab or c225

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Progression free survival	Time from date of randomization until the date of first documented progression or date of death from any cause, whichever came first.	2 year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Objective response rate	CR + PR rate according to RECIST	2 year
Disease control rate	CR + PR + SD rate according to RECIST	2 year
No evidence of disease	The percentage of patients who had a curative treatment following protocol treatment, i.e., liver metastases that can be completely resected and/or ablated with no evidence of residual malignant disease.	2 year
Overall survival	Time from date of randomization until the date of first documented death from any cause.	4 year
Safety (Incidence of Adverse Events)	Percentage of patients, relative to the total of enrolled subjects, experiencing a specific adverse event of grade 3/4, according to National Cancer Institute Common Toxicity Criteria (version 5.0), during the induction and the maintenance phases of treatment.	2 year
Health related quality of life	Scores according to EORTC QLQ-CR29 scoring manual.	Every 2 weeks after the first treatment until 6 months.
Quality-adjusted time without symptoms or toxicity	Q-TWiST was calculated as the sum of the utility-weighted mean durations for each health state. Q-TWiST = (TWiST × μTWiST) + (TOX × μTOX) + (REL × μREL). Base case utilities: μTWiST = 1, μTOX = 0.5, μREL = 0.5. Duration of AEs was measured until disease progression. All time in TOX was front-loaded at the beginning of threrapy.	2 year

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Tumor-infiltrating lymphocyte	Assessment of the tumor-infiltrating lymphocytes (TILs) in tumor tissue before treatment and during tumor progression.	2 year
Treatment-emergent genetic mutations (e.g., KRAS, NRAS, BRAF, SMAD4, HER2, Etc.)	Assessment of the correlation between mutation status of relevant genes and treatment response through ctDNA testing.	2 year

Collaborators and Investigators

• Sponsor: Sun Yat-sen University
• Investigators: Principal Investigator: Yanhong Deng, Ph.D, Sixth Affiliated Hospital, Sun Yat-sen University

Study record dates

Study Major Dates

• Study Start (Actual): November 9, 2023
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2028

Study Registration Dates

• First Submitted: July 16, 2023
• First Submitted That Met QC Criteria: July 24, 2023
• First Posted (Actual): July 25, 2023

Study Record Updates

• Last Update Posted (Estimated): December 17, 2025
• Last Update Submitted That Met QC Criteria: December 9, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: Envafolimab; First-line treatment; RAS/BRAF wild-type; Microsatellite stable(MSS); Unresectable left-side metastatic colorectal cancer
• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Intestinal Diseases; Gastrointestinal Neoplasms; Digestive System Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Intestinal Neoplasms; Rectal Diseases; Colonic Diseases; Colorectal Neoplasms; Amino Acids, Peptides, and Proteins; Proteins; Organic Chemicals; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Camptothecin; Alkaloids; Enzymes and Coenzymes; Antibodies, Monoclonal, Humanized; Antibodies, Monoclonal; Antibodies; Immunoglobulins; Immunoproteins; Blood Proteins; Serum Globulins; Globulins; Coordination Complexes; Pyrimidines; Formyltetrahydrofolates; Tetrahydrofolates; Folic Acid; Pterins; Pteridines; Uracil; Pyrimidinones; Coenzymes; Oxaliplatin; Irinotecan; Cetuximab; Fluorouracil; Leucovorin; envafolimab
• Other Study ID Numbers: GIHSYSU-33

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No