Evaluation of EXL01, a New Live Biotherapeutic Product to Prevent Recurrence of Clostridioides Difficile Infection in High-risk Patients (LIVEDIFF)

Clostridioides difficile infection (CDI) is the leading cause of nosocomial diarrhea in Europe, with over 120,000 cases and almost 3,700 deaths per year. This infection is characterized by a high risk of recurrence after cure, ranging from almost 20% after a first episode to over 60% after 2 recurrences, or in the case of specific risk factors.

Currently, first-line treatment of CDI is based on oral antibiotics such as fidaxomicin or vancomycin. These antibiotic treatments, which are effective in 89% and 86% of first-episode cases respectively, do not correct the microbiological imbalance underlying the onset of CDI and may, on the contrary, encourage recurrence by contributing to the maintenance of a deleterious change in the microbiota (dysbiosis) through the elimination of bacteria other than C. difficile, due to their spectrum of activity. In a number of patients, this ecological imbalance can no longer be restored after antibiotic treatment, leading to multiple recurrences of CDI.

In this context, fecal microbiota transplantation (FMT) has been validated for over 10 years for the prevention of recurrence in multi-recurrent CDI. The principle of FMT is based on the use of a pharmaceutical preparation made from the stool of a healthy donor, administered within the digestive tract of a patient for therapeutic purposes.

Currently, in the case of multiple recurrences, it is the recommended first-line treatment (from 2 recurrences) and the most effective, with a clinical efficacy preventing recurrence of CDI in 69% to 89% of cases at 8 weeks post-treatment, with a good safety profile.

Among the microbial factors promoting CDI, the loss of the bacterial species Faecalibacterium prausnitzii constitutes a specific therapeutic target. F. prausnitzii is a commensal bacterium of the human gut, making up nearly 5% of the fecal microbiota, and has been shown to be associated with an individual's state of health. A drop in its relative abundance is associated with an increased risk of numerous diseases, such as Crohn's disease and colorectal cancer. In CDI, F prausnitzii is greatly diminished. Moreover, low abundance of F. prausnitzii is predictive of C. difficile recurrence. Its abundance in stools is increased after FMT and is also predictive of response to treatment. From a pathophysiological point of view, one of the preventive effects of F. prausnitzii on recurrence would be mediated by its ability to hydrolyze the bile acids involved in the germination of C. difficile spores.

The aim of this Phase I/II trial is to assess the efficacy and safety of oral administration of EXL01, a single isolated unmodified strain of F. prausnitzii, in preventing CDI recurrence in high-risk patients at W8. The study will be conducted in 2 parts. The phase I (Part A) is planned to include 6 patients. The phase II (Part B) will include 50 patients in two arms (25 patients respectively in the placebo and EXL01 arm).

Study Overview

• Status: Recruiting
• Conditions: Clostridioides Difficile Infection; Recurrent Infection
• Intervention / Treatment: Drug: EXL01; Drug: EXL01; Drug: Placebo

• Study Type: Interventional
• Enrollment (Estimated): 56
• Phase: Phase 2; Phase 1

Contacts and Locations

• Study Contact: Name: Nicolas BENECH, MD; Phone Number: +33 04 26 10 94 35; Email: nicolas.benech@chu-lyon.fr
• Study Contact Backup: Name: Fanny JOUBERT; Phone Number: +33 04 26 73 27 27; Email: Fanny.joubert@chu-lyon.fr

Study Locations

• France
  • Annecy, France
    • Not yet recruiting
    • CH Annecy Genevois Service de Maladies infectieuses
    • Contact: Emilie PIET, MD; Phone Number: +33 450636602; Email: epiet@ch-annecygenevois.fr
    • Principal Investigator: Emilie PIET, MD
  • Clermont-Ferrand, France, 63003
    • Recruiting
    • Service d'hépato-gastroentérologie - CHU Estaing
    • Contact: Julien SCANZI, MD; Phone Number: 04 73 75 02 35; Email: jscanzi@chu-clermontferrand.fr
    • Principal Investigator: Julien SCANZI, MD
  • Grenoble, France
    • Not yet recruiting
    • CHU Grenoble Service Maladies infectieuses et tropicales
    • Contact: Salomé GALLET, MD; Phone Number: +33 476763947; Email: sgallet@chu-grenoble.fr
    • Principal Investigator: Salomé GALLET, MD
  • Lyon, France, 69004
    • Recruiting
    • Service d'Hépato-gastroentérologie Hôpital de la Croix Rousse
    • Contact: Nicolas BENECH, MD; Phone Number: +33 04 26 10 94 35; Email: nicolas.benech@chu-lyon.fr
    • Principal Investigator: Nicolas BENECH, MD
    • Contact: Emma SANDOZ; Phone Number: +33 04 26 73 28 62; Email: emma.sandoz@chu-lyon.fr
  • Marseille, France
    • Recruiting
    • APHM La Timone Service de Maladies infectieuses
    • Contact: Nadim CASSIR, MD; Email: nadimshams.cassir@ap-hm.fr
    • Principal Investigator: Nadim CASSIR, MD
  • Paris, France, 75012
    • Recruiting
    • Service d'hépato-gastroentérologie - Hôpital Saint Antoine (APHP)
    • Contact: Paul MCLELLAN, MD; Phone Number: +33 01 49 28 20 00; Email: Paul.mclellan@aphp.fr
    • Principal Investigator: Paul MCLELLAN, MD
  • Saint-Etienne, France, 42100
    • Not yet recruiting
    • Service d'infectiologie - Hôpital Nord / CHU Saint Etienne
    • Contact: Elisabeth BOTHELO-NEVERS, Pr; Phone Number: +33 04 77 12 77 89; Email: elisabeth.botelho-nevers@chu-st-etienne.fr
    • Principal Investigator: Elisabeth BOTHELO-NEVERS, Pr
  • Toulouse, France, 31059
    • Recruiting
    • Service de médecine interne - Pôle des maladies de l'appareil digestif - CHU de Toulouse
    • Principal Investigator: Laurent ALRIC, Pr
    • Contact: Laurent ALRIC, Pr; Phone Number: 05 61 32 37 54; Email: Alric.l@chu-toulouse.fr
  • Valence, France, 26000
    • Recruiting
    • Service de Maladies Infectieuses - CH de Valence
    • Contact: Amélie DUREAULT, MD; Phone Number: +33 04 75 75 75 71; Email: adureault@ch-valence.fr
    • Principal Investigator: Amélie DUREAULT, MD

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Adult patient ≥18 years of age

• ≥3rd episode of proven C. difficile infection (≥3 liquid stools per day and detection of toxigenic C. difficile in stool by PCR or enzyme-linked immunosorbent assay or immunochromatography or toxigenic culture) within 6 months with an interval ≤ 12 weeks since the end of treatment of the previous episode of resolved CDI or 2nd episode of proven C. difficile infection (≥3 liquid stools per day and detection of toxigenic C. difficile in the stools by PCR or enzyme-linked immunosorbent assay or immunochromatography or toxigenic culture) within 6 months with an interval ≤ 12 weeks since the end of treatment of the previous episode of resolved CDI with at least one of the following risk factors:

  • Age ≥70 years
  • Chronic renal failure (haemodialysis or GFR<60ml/min
  • History of severe or severe-complicated CDI (excluding current episode) according to ESCMID 2021 criteria
  • ≥3 CDI in the last 12 months (including current episode)
  • CDI associated with care defined as CDI occurring during hospitalisation (<3 months)
• On current or planned vancomycin treatment per os
• Patient able to give free, informed and written consent
• Enrolled in compulsory national social security scheme

Exclusion Criteria:

• Currently participating or has participated in a study with an investigational compound or device within 3 months prior to the first dose of the study intervention.
• Severe C. difficile infection severe (defined by the presence of a white blood cell count >15×10⁹ cells/L or a body temperature >38.5°C or >50% increase in the patient's baseline creatinine related to CDI at the time of V1) and/or complicated (defined by any of the factors attributed to current Clostridioides difficile infection (CDI): hypotension, septic shock, elevated serum lactate, ileus, toxic megacolon, intestinal perforation or any fulminant course of the disease)
• Refractory C. difficile infection defined as lack of response to well-conducted per os vancomycin or fidaxomicin treatment with ≥3 liquid stools per day after ≥5 days of treatment
• Cirrhosis with Child C score
• Hospitalization in continuing care unit or intensive care unit

• Immunosuppression including :

  • Malignant hemopathy under treatment (excluding CLL)
  • HIV AIDS stage
  • Stem cell allograft ≤ 12 months
  • Aplasia (<500 PNN/mm3) at inclusion
  • Treatment with >20mg prednisone equivalent within 14 days prior to inclusion (excluding inhaled or topical treatment).
• Personal history of gastrointestinal resection other than appendectomy (gastrectomy, esophagectomy, colonic or small bowel resection, short small bowel syndrome).
• Personal history of small intestinal microbial overgrowth
• Inflammatory bowel disease
• Proven celiac disease
• Current stoma (ileostomy or colostomy) or within the last 6 months, or any other intra-abdominal surgery within the 3 months prior to treatment
• major surgery or trauma ≤ 4 weeks before the start of treatment
• Antibiotic therapy in progress or planned during the study for an infection other than CDI
• Surgery scheduled during the study requiring perioperative antibiotics.
• -Women without contraception*, pregnant or breastfeeding women
• History of hypersensitivity to EXL01 and/or to any of its excipients (D-mannitol, sucrose, maltodextrin, L-cysteine, L-cysteine hydrochloride, magnesium stearate and hydroxypropylmethylcellulose), and/or to soy or soy-containing products.
• History of hypersensitivity to vancomycin as mentioned in local prescribing information.
• Personal history of fecal microbiota transplantation < 12 months
• Persons deprived of liberty by judicial or administrative decision
• Adults under legal protection or unable to give consent
• Swallowing disorders making oral treatment impossible
• Participation in another interventional study within 3 months prior to inclusion. (Patients who have entered the follow-up phase of an interventional study may participate provided that more than 3 months have elapsed since the last intervention).
• Expected life expectancy of less than 6 months
• Presents a known psychiatric disorder that would interfere with adequate cooperation with study requirements.
• Regular use of illicit or recreational drugs
• Anticipated administration during the study of treatment that is expected to cause diarrhea (chemotherapy, colonic preparation prior to colonoscopy)
• History of chronic diarrhea (> 3 watery stools per day for > 4 weeks) not related to gastrointestinal infection.
• Clinically significant medical or surgical condition not mentioned in the above criteria which, in the opinion of the investigator, could interfere with the administration of study drug, the interpretation of study safety or efficacy data, or compromise the safety or well-being of the subject.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Part A (Open-Label EXL01)	Drug: EXL01; Following a at least 10-days vancomycin treatment : Oral EXL01 including: 10 capsules per day in week 1 and 2; 4 capsules per day, in weeks 3 and 4; 1 capsule per day in weeks 5 to 8 Phase I : EXL01 during a 8 weeks open-label period; Drug: EXL01; Following a at least 10-days vancomycin treatment : Oral EXL01 including: 10 capsules per day in week 1 and 2; 4 capsules per day, in weeks 3 and 4; 1 capsule per day in weeks 5 to 8 Phase II: EXL01 during a 8 weeks double blind placebo-controlled period
Experimental: Part B (EXL01)	Drug: EXL01; Following a at least 10-days vancomycin treatment : Oral EXL01 including: 10 capsules per day in week 1 and 2; 4 capsules per day, in weeks 3 and 4; 1 capsule per day in weeks 5 to 8 Phase I : EXL01 during a 8 weeks open-label period; Drug: EXL01; Following a at least 10-days vancomycin treatment : Oral EXL01 including: 10 capsules per day in week 1 and 2; 4 capsules per day, in weeks 3 and 4; 1 capsule per day in weeks 5 to 8 Phase II: EXL01 during a 8 weeks double blind placebo-controlled period
Placebo Comparator: Part B (Placebo)	Drug: Placebo; Following a at least 10-days vancomycin treatment: Oral placebo including: 10 capsules per day in week 1 and 2; 4 capsules per day, in weeks 3 and 4; 1 capsule per day in weeks 5 to 8 Phase II : Placebo during a 8 weeks double blind placebo-controlled period

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of Treatment-Emergent Adverse Events	Phase I The primary endpoint is the occurrence of serious adverse events (CTCAE grade≥3) during treatment and follow-up and discontinuation of treatment due to adverse events attributed to treatment	at Week 1, Week 2, Week 4, Week 8, Week 16
Evaluation of the efficacy of EXL01 in preventing recurrence of C. difficile infection in patients at high risk of recurrence	Phase II The primary endpoint is the proportion of patients at W8 after the start of treatment who had a recurrence of toxigenic C. difficile defined by ≥3 liquid stools per day for more than 48 hours + detection of C. difficile toxin in stool (enzyme-linked immunosorbent assay or toxigenic culture +/- PCR) resulting in the initiation of CDI-specific treatment.	at Week 8

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Evaluation of the presence of EXL01 in the fecal microbiota	Phases I and II Level of F. prausnitzii (qPCR) in stool at W8 versus W0	At Week 8
Assessment of recurrences of C. difficile infection requiring hospitalization	phases I and II percentage of patients with recurrence of C. difficile infection requiring hospitalization at W8	At Week 8
Assessment of recurrences of C. difficile infection requiring surgery	phases I and II phases I and II percentage of patients with a recurrence of C. difficile infection requiring surgery at W8	at Week 8
Evaluation of the efficacy of EXL01 in preventing recurrence of C. difficile infection in patients at high risk of recurrence	Phase I Proportion of patients at W8 after the start of treatment who had a recurrence of toxigenic C. difficile defined by ≥3 liquid stools per day for more than 48 hours + detection of C. difficile toxin in stool (enzyme-linked immunosorbent assay or toxigenic culture +/- PCR) resulting in the initiation of specific treatment for CDI.	at Week 8
Evaluation of the safety and tolerability profile of oral EXL01	Phase II Occurrence of adverse events (CTCAE grade≥3) during treatment and follow-up, and discontinuation of treatment due to adverse events	at Week 2, Week 4, Week 8, Week 16
Number of stools per day over the past 24 hours	Phase I Assessment of digestive symptoms during treatment and follow-up Digestive symptoms are measured at each visit using a stool calendar	at Week 0, Week 1, Week 2, Week 4, Week 8, Week 16
Stool consistency, as assessed by the Bristol scale, over the past 24 hours	Phase I Digestive symptoms are measured at each visit using the stool calendar	at Week 0, Week 1, Week 2, Week 4, Week 8, Week 16
Abdominal discomfort assessed by a validated irritable bowel syndrome scale	Phase I Assessment of digestive symptoms during treatment and follow-up Digestive symptoms are measured at each visit (IBS-SSS modified, GCSI, GERDQ)	at Week 8, Week 16
Number of stools per day over the past 24 hours	Phase II Assessment of digestive symptoms during treatment and follow-up Digestive symptoms are measured at each visit using a stool calendar	at Week 0, Week 2, Week 4, Week 8, Week 16
Stool consistency, as assessed by the Bristol scale, over the past 24 hours	Phase II Digestive symptoms are measured at each visit using the stool calendar	at Week 0, Week 2, Week 4, Week 8, Week 16
Abdominal discomfort assessed by a validated irritable bowel syndrome scale	Phase II Assessment of digestive symptoms during treatment and follow-up Digestive symptoms are measured at each visit (IBS-SSS modified, GCSI, GERDQ)	at Week 8, Week 16
Assessment of patient quality of life during treatment and follow-up	Phases I and II Patient quality of life at W8 and M4 measured by a validated digestive disease quality of life questionnaire (GIQLI)	At Week 8 and Week 16
Assessment of recurrence of C. difficile infection	Phases I and II percentage of patients with recurrence of C. difficile infection at M4	At Week 16
Assessment of EXL01 persistence in the intestinal microbiota	Phases I and II Level of F. prausnitzii (qPCR) in stool at M4 versus W0	At Week 0 and Week 16
16S rRNA sequencing or shotgun	Phase I Gut microbiota composition at each visit	at Week 0, Week 1, Week 2, Week 4, Week 8, Week 16
16S rRNA sequencing or shotgun	Phase II Gut microbiota composition at each visit	at Week 0, Week 2, Week 4, Week 8, Week 16
Assessment of the persistence of toxigenic C. difficile in the stool of patients in clinical remission during the study.	Phase I Percentage of patients at each visit with a positive stool PCR test for toxigenic C. difficile considered to be in clinical remission	at Week 0, Week 1, Week 2, Week 4, Week 8, Week 16
Assessment of the persistence of toxigenic C. difficile in the stool of patients in clinical remission during the study.	Phase II Percentage of patients at each visit with a positive stool PCR test for toxigenic C. difficile considered to be in clinical remission	at Week 0, Week 2, Week 4, Week 8, Week 16
Assessment of recurrences of C. difficile infection requiring hospitalization	phases I and II percentage of patients with recurrence of C. difficile infection requiring hospitalization at M4	at Week 16
Assessment of recurrences of C. difficile infection requiring surgery	phases I and II percentage of patients with recurrent C. difficile infection requiring surgery at M4	at Week 16

Collaborators and Investigators

• Sponsor: Hospices Civils de Lyon
• Collaborators: Exeliom Biosciences
• Investigators: Principal Investigator: Nicolas BENECH, MD, Hospices Civils de Lyon

Study record dates

Study Major Dates

• Study Start (Actual): May 7, 2024
• Primary Completion (Estimated): January 7, 2027
• Study Completion (Estimated): January 7, 2027

Study Registration Dates

• First Submitted: February 21, 2024
• First Submitted That Met QC Criteria: March 5, 2024
• First Posted (Actual): March 12, 2024

Study Record Updates

• Last Update Posted (Actual): May 15, 2026
• Last Update Submitted That Met QC Criteria: May 13, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Microbiota; Live Biotherapeutic Product; Recurrent Infection; Clostridioides difficile Infection
• Additional Relevant MeSH Terms: Pathologic Processes; Disease Attributes; Infections; Gram-Positive Bacterial Infections; Bacterial Infections; Bacterial Infections and Mycoses; Recurrence; Pathological Conditions, Signs and Symptoms; Reinfection; Clostridium Infections; Substandard Drugs; Pharmaceutical Preparations; Counterfeit Drugs
• Other Study ID Numbers: 69HCL22_0980; 2023-506232-32-00 (Other Identifier: EU CT Number)

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