Effects of High-Fiber Diet on Gut Microbiota, Metabolism, and Immune Microenvironment in Solid Tumor Patients: A Clinical Study

NCT07477522 | Recruiting Phase 1 DMC

• 1 other identifier: Approval No. 1038 (2025)
• Study Type: interventional
• Target: 25
• Locations: 1 country
• Sites: 1

Brief Summary

Cancer remains a major global public-health challenge and a central focus of medical research. According to the International Agency for Research on Cancer (IARC, 2020), 19.29 million new malignant tumors and 9.96 million cancer deaths occurred worldwide, \>90 % being solid cancers. Lung cancer alone accounted for 2.2 million new cases and 1.8 million deaths; \>75 % of patients were already at an advanced stage at diagnosis. Current options for late-stage solid tumors are limited: surgery is often impossible because of metastasis; cytotoxic chemotherapy produces dose-limiting toxicities (grade Ⅲ-Ⅳ myelosuppression 15-40 %, mucositis 50-80 %); radiotherapy risks pneumonitis (5-15 %) or enteritis (5-20 %) when tumors abut vital organs; targeted agents succumb to acquired resistance after a median 9-13 months; and immune-checkpoint inhibitors achieve \<40 % objective response with 7-15 % grade 3-4 immune-related adverse events. Dietary intervention is therefore emerging as a promising adjunct. Dietary fibre protects against cardiovascular and metabolic diseases, yet intake is universally low. WHO and the Chinese Nutrition Society recommend 25-30 g total fibre per day (≈15-21 g insoluble), whereas Chinese adults consume only \~11 g insoluble fibre. High-fibre diets reshape gut microbiota, augment short-chain fatty acid (SCFA) production, strengthen intestinal barrier function, activate CD8⁺ T cells and dampen regulatory T cells, thereby enhancing anti-tumour immunity. A melanoma cohort showed improved progression-free survival under immunotherapy when fibre intake was high. Similar microbiota-immune axes may operate in colorectal and other solid cancers, but clinical data are scarce. We therefore propose a study to examine whether a high-insoluble-fibre diet (\>21 g/day) modulates gut-microbiota composition, metabolite profiles and peripheral-blood immune subsets in solid-tumour patients, and to evaluate consequent effects on treatment response and quality of life. The findings will clarify whether fibre-driven microbiota-immune crosstalk can be harnessed as a personalised nutritional strategy to improve cancer outcomes.

Conditions

Colorectal Cancer (Diagnosis); Diet Habits; High-fibre Diet

Keywords

high-fibre diet; Colorectal Cancer

Outcome Measures

Primary Outcomes (1)

• Evaluate the safety and tolerability of High-fibre diet in patients with solid tumors.

  The occurrence types, frequencies, and severities of treatment - emergent adverse events (TEAE).

  From enrollment to the end of treatment at 6 weeks

Secondary Outcomes (3)

• Objective Response Rate (ORR)

  From enrollment to the end of treatment at 1 year

• Disease Control Rate (DCR)

  From enrollment to the end of treatment at 1 year

• Duration of Response (DoR)

  From enrollment to the end of treatment at 1 year

Study Arms (1)

high-insoluble-fibre diet

EXPERIMENTAL

Dietary Supplement: High-fibre diet

Interventions

High-fibre diet DIETARY_SUPPLEMENT

Dietary fibre, recommended at 25-30 g/d (15-21 g insoluble), is chronically under-consumed (\~11 g/d in China). High-fibre diets increase SCFAs, enhance gut-barrier integrity and boost anti-tumour immunity, correlating with better immunotherapy outcomes in melanoma. Clinical evidence in solid tumours is lacking. Our trial will test whether \>21 g/d insoluble fibre reshapes microbiota, metabolites and immune markers in solid-cancer patients and improves treatment response and quality of life, providing rationale for microbiota-targeted nutrition.

high-insoluble-fibre diet

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• (1) Sign a written informed consent form before any study - related procedures are carried out.
• (2) Males or females, aged 18 - 80 years old. (3) Diagnosed with solid tumors by pathological tissue biopsy. (4) According to the RECIST v1.1 (Response Evaluation Criteria in Solid Tumors Version 1.1) criteria, there is at least 1 measurable lesion (lesions previously treated with local therapies such as radiotherapy cannot be regarded as measurable lesions).
• (5) ECOG (Eastern Cooperative Oncology Group Performance Status) score of 0 - 1.
• (6) NRS - 2002 (Nutritional Risk Screening 2002) score \< 3. (7) BMI (Body Mass Index) ≥ 18.5 (can be adjusted appropriately according to the actual situation).
• (8) Patients who can eat orally or through a feeding tube and can tolerate enteral nutrition.
• (9) Sufficient organ function, and the subjects need to meet the following laboratory indicators: In the absence of granulocyte - colony - stimulating factor use in the past 14 days, the absolute neutrophil count ≥ 1.5×10⁹/L.
• Platelets ≥ 75×10⁹/L. In the absence of blood transfusion or erythropoietin use in the past 7 days, hemoglobin ≥ 8 g/dL.
• Serum albumin ≥ 3.0 g/dL. Total bilirubin ≤ 1.5× the upper limit of normal (ULN). Aspartate Aminotransferase (AST) and Alanine Aminotransferase (ALT) ≤ 2.5×ULN. In case of liver metastasis, ALT and/or AST ≤ 5×ULN, and total bilirubin ≤ 3×ULN. In case of liver or bone metastasis, Alkaline Phosphatase (AKP) ≤ 5×ULN.
• Creatinine clearance rate ≥ 50 mL/min (calculated according to the Cockcroft - Gault formula) or serum creatinine ≤ 1.5×ULN.
• International Normalized Ratio (INR) ≤ 1.5×ULN, Prothrombin Time (PT) and Activated Partial Thromboplastin Time (APTT) ≤ 1.5×ULN.
• Urine protein \< 2+ (if urine protein ≥ 2+, a 24 - hour urine protein quantification can be performed, and subjects with a 24 - hour urine protein quantification \< 2.0 g can be enrolled).
• (10) Women of child - bearing potential must agree to avoid sexual intercourse (heterosexual intercourse) or use a reliable and effective contraceptive method from the signing of the informed consent form until at least 6 months after the last administration of the study drug. In addition, the serum HCG (Human Chorionic Gonadotropin) test must be negative within 3 days before the start of the study treatment, and the subject must be non - lactating. A female patient is considered to be of child - bearing potential if she is post - menopausal but has not reached the post - menopausal state (non - menstrual period ≥ 12 consecutive months, and no other causes are found except menopause) and has not undergone sterilization surgery (such as hysterectomy, bilateral tubal ligation, or bilateral oophorectomy).
• (11) If there is a risk of pregnancy, all subjects (regardless of male or female) need to use a contraceptive method with an annual failure rate of less than 1% throughout the treatment period until 120 days after the last administration of the study drug (or 180 days after the last administration of the chemotherapy drug)

You may not qualify if:

• (1) Patients with cognitive impairment or mental illness who are unable to understand the study content.
• (2) Patients with central nervous system or meningeal metastases. (3) Patients with clinically symptomatic moderate or severe ascites (that is, those who require therapeutic paracentesis within 2 weeks before the start of study treatment; patients with only a small amount of ascites shown on imaging and no clinical symptoms can be enrolled).
• (4) Patients with uncontrolled or moderate to severe pleural effusion and pericardial effusion.
• (5) Patients with severe diarrhea, intractable vomiting, severe malabsorption syndrome, paralytic and mechanical intestinal obstruction; tracheoesophageal fistula, gastrointestinal perforation or gastrointestinal fistula, or abdominal abscess; patients with extra - gastrointestinal bleeding with a CTCAE (Common Terminology Criteria for Adverse Events) grade 3 or above within 6 months before the start of study treatment or grade 2 or above within 3 months (such as abnormal vaginal bleeding, hematemesis).
• (6) Patients known to be allergic to the active ingredients or excipients of the study drug.
• (7) Patients with poorly controlled diabetes. (8) Patients with poorly controlled hypertension (systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg under routine antihypertensive treatment), with a history of hypertensive crisis or hypertensive encephalopathy.
• (9) Patients with severe cardiovascular and cerebrovascular diseases, including cerebrovascular accident (CVA), transient ischemic attack (TIA), myocardial infarction, and major vascular diseases within 6 months before enrollment (including but not limited to aortic aneurysms requiring surgical repair or recent arterial thrombosis); patients with poorly controlled clinical symptoms or heart diseases, such as unstable angina pectoris, NYHA (New York Heart Association) heart failure grade II or above, left ventricular ejection fraction \< 50% on color Doppler echocardiography, or severe arrhythmias that cannot be controlled by drug treatment.
• (10) Pregnant or lactating women. (11) Other situations considered by the investigator as inappropriate for enrollment.

Sponsors & Collaborators

• West China Hospital: lead

Study Sites (1)

West China Hospital

Chengdu, Sichuan, China

RECRUITING

MeSH Terms

Conditions

Colorectal Neoplasms; Disease; Feeding Behavior

Condition Hierarchy (Ancestors)

Intestinal Neoplasms; Gastrointestinal Neoplasms; Digestive System Neoplasms; Neoplasms by Site; Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Colonic Diseases; Intestinal Diseases; Rectal Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Behavior, Animal; Behavior

Central Study Contacts

Jingwen Wei

CONTACT

8283095730; jingwenwinni@163.com

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Deputy Director (Medical) of the Department of Biotherapy, Cancer Center, West China Hospital, Sichuan University; Associate Director of the Stem Cell Research and Translational Research Laboratory; PhD Supervisor; Professor/Researcher

Model Details: high-fibre diet

Study Record Dates

• First Submitted: March 12, 2026
• First Posted: March 17, 2026
• Study Start: October 31, 2025
• Primary Completion: June 30, 2026
• Study Completion: June 30, 2026
• Last Updated: March 17, 2026

Record last verified: 2025-10

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)