Clinical trial Recruiting at 1 site Interventional Ages 18 and up

Dietary fiber intervention to reduce immunotherapy side effects

Official title: Food Intervention to Reduce Immunotherapy ToXicity

Run by Universitair Ziekenhuis Brussel · NCT05832606 · Data updated 2026-11-12

This study is testing if eating more fiber from a variety of plants can help people with solid tumors have fewer side effects from their immunotherapy treatment.

Quick facts

Study typeInterventional
Ages18 Years and up
SexAll
Enrollment60 (estimated)
SponsorUniversitair Ziekenhuis Brussel
Academic / other
Drugs / interventionschemotherapy, immunotherapy
Locations1 site (Jette)
StatusRecruiting
StartedJanuary 1, 2024
Main results expectedJuly 31, 2026
Study endsDecember 31, 2026
Registry record updatedMarch 26, 2025
Trial IDNCT05832606 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Ideal candidates are patients with solid tumors who are starting treatment with anti-PD1 or anti-CTLA4 antibodies.

Probably not a fit

Patients who cannot take oral intake or are currently using probiotics may not benefit from this study.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

The FORX trial aims to determine if increasing dietary fiber intake through weekly boxes of 30 different plants can reduce immune-related adverse events (irAEs) in patients with solid tumors undergoing immune checkpoint inhibitor therapy. This innovative approach is based on the premise that a diverse gut microbiome, supported by a fiber-rich diet, can enhance tolerance to immunotherapy. Participants will receive these food boxes for the first 12 weeks of their treatment, and their stool and blood samples will be analyzed to understand the relationship between diet, gut microbiome, and irAEs. The trial seeks to provide actionable dietary recommendations to improve patient outcomes and quality of life.

Why it matters

Potential benefit: If successful, this intervention could significantly reduce the incidence of side effects from immunotherapy, enhancing patient quality of life and treatment adherence.

How similar studies have gone: While the approach of dietary intervention in this context is novel, previous studies have indicated that dietary diversity can positively influence gut microbiome health.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

* solid tumor starting anti-programmed cell death protein 1 (anti-PD1) and/or anti-cytotoxic T-lymphocyte-associated antigen 4 (anti-CTLA4) antibodies as part of standard of care.
* able to sign informed consent.

Exclusion Criteria:

* no oral intake possible.
* probiotic use and unwillingness to stop during the trial.
* combination therapy with chemotherapy or targeted agents.

Where it's running

  • UZ Brussel
    Jette, Belgium
    Recruiting

Study contacts

  • Principal investigator: Sandrine Aspeslagh, MD PhD — Vrije Universiteit Brussel (VUB), Universitair Ziekenhuis Brussel (UZ Brussel)
  • Study coordinator: Marthe Verhaert, MD
  • Email: marthe.verhaert@uzbrussel.be
  • Phone: +3224749480

Similar studies

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How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.