Clostridioides Difficile Infection RecurrenceNCT07250724
C. Difficile Toxin Levels in Stool From Healthy Individuals Following Standard of Care Antibiotic Treatment for CDI.
An observational study of Clostridioides Difficile Infection Recurrence, run by Bactolife A/S at 4 sites in United States.
Trial summary
Hospitals and clinics interested in participating in this multi-site study, please contact the people mentioned under "Contacts and Locations". The goal of this study is to map the risk of having a C. Difficile infection recurrence (rCDI) after being treated with standard-of-care antibiotics for a C. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Clostridioides Difficile Infection Recurrence
- How many people
- 60 participants
- Where
- 4 sitesUnited States
- Study dates
- 1 Mar 2026to 31 Jan 2027
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: This prospective observational study will enrol 60 otherwise healthy adults with a documented history of first recurrent Clostridioides difficile infection (rCDI). Eligible participants must have had a confirmed positive toxin B test for C. difficile, with the initial infection occurring within the past 12 months. At the time of enrolment (Day 0), participants must have completed a standard-of-care oral antibiotic therapy for their first rCDI no more than five days prior and be asymptomatic for CDI. Potential participants will sign an informed consent form at their initial visit to their doctor (visit 1) and provide a stool sample for c diff testing. Participants will only be considered 'enrolled' if their stool sample is positive for toxin B and they meet all criteria at visit 2.
Who may be able to join
None listed.
Who cannot join
- Participants will be excluded from the study if they meet any of the following criteria:
- At the time of screening:
- Planned CDI recurrence treatment for the planned 8-week duration of study participation (I.e., Fecal microbiome transplant, Rebyota, Vowst, Live Biotherapeutic Products (LBPs), probiotics etc)
- Pregnant or lactating women or women who intend/wish to become pregnant in the time period in between screening and visit 4
- Has any significant acute or chronic coexisting health conditions that would prevent them from fulfilling the study requirements, put the Participant at risk or would confound the interpretation of the study results as judged by the investigator on the basis of medical history and routine laboratory test results. I.e.: Ostomized participants, Parenteral nutrition users, Patients with active Pancreatitis, Active, non-controlled intestinal diseases such as IBS, IBD, Crohn's Disease, ulcerative colitis, celiac disease, or other chronic diarrheal illness
- Currently or recently taking a medication that the investigator believes would interfere with the objectives of the study or pose a safety risk or confound the interpretation of the study results.
Show all 11Show fewer
- Individuals who, in the opinion of the investigator, are considered to be poor study attendees or unlikely for any reason to be able to comply with the study.
- Participants may not be participating in other clinical studies, or planning to do so during participating in the present study. If the participant has previously taken part in an experimental study, the Investigator must ensure sufficient time has elapsed before entry to this study to ensure the integrity of the results.
- At the time of baseline visit:
- Lack of CDI symptom resolution following the SoC antibiotic regime. I.e. still active diarrhoea (3 or more stools per 24-hour period) and within Bristol stool scale range of 5-7 at baseline.
- Those who are on, or during study participation plan to go on, antibiotic treatment for any reason.
Trial locations and contacts
4 sites in 1 country.
United States4 sites
Emory University Hospital
Atlanta, Georgia, 30322
University of Wisconsin-Madison
Madison, Wisconsin, 53705-2281
Mayo Clinic, Minnesota
Rochester, Minnesota, 55905
Corewell Health William Beaumont University Hospital
Royal Oak, Michigan, 48073
About this study
Official title: A Prospective, Observational Study to Evaluate C. Difficile Toxin Levels in Stool in Healthy Individuals Following Standard of Care Antibiotic Treatment for CDI.
Hospitals and clinics interested in participating in this multi-site study, please contact the people mentioned under "Contacts and Locations".
The goal of this study is to map the risk of having a C. Difficile infection recurrence (rCDI) after being treated with standard-of-care antibiotics for a C. Difficile infection.
Read more
The main questions it aims to answer are:
- What is the recurrence rate of CDI in the 8 weeks following antibiotic treatment for a first recurrence of CDI?
- Does toxin levels of Toxin A and/or B from C. Diff. at baseline predict CDI recurrence risk?
Participants will:
- Undergo standard of care Antibiotic treatment for first recurrence of CDI
- Visit their clinic at 4 different visits over a time period of approximately 9 weeks. (Visits can also be performed remote/via phone call.)
Read the detailed description
Hospitals and clinics interested in participating in this multi-site study, please contact the people mentioned under "Contacts and Locations".
This prospective observational study will enrol 60 otherwise healthy adults with a documented history of first recurrent Clostridioides difficile infection (rCDI). Eligible participants must have had a confirmed positive toxin B test for C. difficile, with the initial infection occurring within the past 12 months. At the time of enrolment (Day 0), participants must have completed a standard-of-care oral antibiotic therapy for their first rCDI no more than five days prior and be asymptomatic for CDI. Potential participants will sign an informed consent form at their initial visit to their doctor (visit 1) and provide a stool sample for c diff testing. Participants will only be considered 'enrolled' if their stool sample is positive for toxin B and they meet all other criteria at visit 2 (week 0).
The primary objective of the study is to measure the rate of CDI recurrence within an 8-week follow-up period. The secondary objective is to assess stool levels of Toxin A and B at baseline, week 2, and week 8. The second objective will enable exploration of the reliability of using high-sensitivity assays for toxin detection in stool. Further, potential correlations between post-treatment stool toxin levels and rCDI development will be explored.
- Being tested
- Participants that are undergoing standard of care antibiotic treatment for their second C. Diff infection will be followed for 8 weeks after completing antibiotic treatment.
- Keywords
- C. Diff, Clostridioides Difficile, Clostridioides Difficile Infection, Clostridioides Difficile Infection Recurrence, Clostridioides Difficile Recurrence, C. Diff recurrence
- Medical subject headings
- Clostridium Infections
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Participants that are undergoing standard of care antibiotic treatment for their second C. Diff infection will be followed for 8 weeks after completing antibiotic treatment.Other
Participants that are undergoing standard of care antibiotic treatment for their second C. Diff infection will be followed for 8 weeks after completing antibiotic treatment.
What is being measured
The primary outcome is the main question the study is designed to answer.
The proportion of subjects experiencing CDI recurrence in the time period between baseline and end of study follow-up.
CDI recurrence will be defined as the development of a new episode of diarrhoea (3 or more loose stools in 24 or fewer hours) associated with a positive stool test for toxigenic C. difficile following clinical cure of the initial CDI episode.
Measured: Within the 8 week time period between baseline and end of follow-up
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted26 Nov 2025
- Study start1 Mar 2026
- Primary completion15 Jan 2027 (estimated)
- Study completion31 Jan 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Clostridioides Difficile Infection RecurrenceStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 60 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Bactolife A/S
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Brynjulf Mortensen, pHD, Study director, Bactolife A/S
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07250724
- Sponsor's protocol ID
- AFCRO-193
- Status last verified
- Nov 2026
- First submitted
- 26 Sep 2025
- Last updated
- 4 Nov 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 4 Nov 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Prospective, Observational Study to Evaluate C. Difficile Toxin Levels in Stool in Healthy Individuals Following Standard of Care Antibiotic Treatment for CDI.
- ClinicalTrials.gov ID
- NCT07250724
- Acronym / sponsor ID
- AFCRO-193
- Keywords
- C. Diff, Clostridioides Difficile, Clostridioides Difficile Infection, Clostridioides Difficile Infection Recurrence, Clostridioides Difficile Recurrence, C. Diff recurrence
- Study type
- Observational
- Recruitment status
- Active, not recruiting
- Enrolment
- 60 participants (estimated)
- Lead sponsor
- Bactolife A/SIndustry (pharma, biotech, devices)
- Study start
- 1 Mar 2026 (actual)
- Primary completion
- 15 Jan 2027 (estimated)
- Study completion
- 31 Jan 2027 (estimated)
- First posted
- 26 Nov 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Hospitals and clinics interested in participating in this multi-site study, please contact the people mentioned under "Contacts and Locations".
The goal of this study is to map the risk of having a C. Difficile infection recurrence (rCDI) after being treated with standard-of-care antibiotics for a C. Difficile infection.
The main questions it aims to answer are:
- What is the recurrence rate of CDI in the 8 weeks following antibiotic treatment for a first recurrence of CDI?
- Does toxin levels of Toxin A and/or B from C. Diff. at baseline predict CDI recurrence risk?
Participants will:
- Undergo standard of care Antibiotic treatment for first recurrence of CDI
- Visit their clinic at 4 different visits over a time period of approximately 9 weeks. (Visits can also be performed remote/via phone call.)
Detailed description
Hospitals and clinics interested in participating in this multi-site study, please contact the people mentioned under "Contacts and Locations".
This prospective observational study will enrol 60 otherwise healthy adults with a documented history of first recurrent Clostridioides difficile infection (rCDI). Eligible participants must have had a confirmed positive toxin B test for C. difficile, with the initial infection occurring within the past 12 months. At the time of enrolment (Day 0), participants must have completed a standard-of-care oral antibiotic therapy for their first rCDI no more than five days prior and be asymptomatic for CDI. Potential participants will sign an informed consent form at their initial visit to their doctor (visit 1) and provide a stool sample for c diff testing. Participants will only be considered 'enrolled' if their stool sample is positive for toxin B and they meet all other criteria at visit 2 (week 0).
The primary objective of the study is to measure the rate of CDI recurrence within an 8-week follow-up period. The secondary objective is to assess stool levels of Toxin A and B at baseline, week 2, and week 8. The second objective will enable exploration of the reliability of using high-sensitivity assays for toxin detection in stool. Further, potential correlations between post-treatment stool toxin levels and rCDI development will be explored.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- This prospective observational study will enrol 60 otherwise healthy adults with a documented history of first recurrent Clostridioides difficile infection (rCDI). Eligible participants must have had a confirmed positive toxin B test for C. difficile, with the initial infection occurring within the past 12 months. At the time of enrolment (Day 0), participants must have completed a standard-of-care oral antibiotic therapy for their first rCDI no more than five days prior and be asymptomatic for CDI. Potential participants will sign an informed consent form at their initial visit to their doctor (visit 1) and provide a stool sample for c diff testing. Participants will only be considered 'enrolled' if their stool sample is positive for toxin B and they meet all criteria at visit 2.
Key inclusion criteria (0 listed)
Key exclusion criteria (11 listed)
- Planned CDI recurrence treatment for the planned 8-week duration of study participation (I.e., Fecal microbiome transplant, Rebyota, Vowst, Live Biotherapeutic Products (LBPs), probiotics etc)
- Pregnant or lactating women or women who intend/wish to become pregnant in the time period in between screening and visit 4
- Has any significant acute or chronic coexisting health conditions that would prevent them from fulfilling the study requirements, put the Participant at risk or would confound the interpretation of the study results as judged by the investigator on the basis of medical history and routine laboratory test results. I.e.: Ostomized participants, Parenteral nutrition users, Patients with active Pancreatitis, Active, non-controlled intestinal diseases such as IBS, IBD, Crohn's Disease, ulcerative colitis, celiac disease, or other chronic diarrheal illness
- Currently or recently taking a medication that the investigator believes would interfere with the objectives of the study or pose a safety risk or confound the interpretation of the study results.
- Individuals who, in the opinion of the investigator, are considered to be poor study attendees or unlikely for any reason to be able to comply with the study.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Participants that are undergoing standard of care antibiotic treatment for their second C. Diff infection will be followed for 8 weeks after completing antibiotic treatment.Participants that are undergoing standard of care antibiotic treatment for their second C. Diff infection will be followed for 8 weeks after completing antibiotic treatment. | Other | – |
Primary outcome
The proportion of subjects experiencing CDI recurrence in the time period between baseline and end of study follow-up.
Time frame: Within the 8 week time period between baseline and end of follow-up
CDI recurrence will be defined as the development of a new episode of diarrhoea (3 or more loose stools in 24 or fewer hours) associated with a positive stool test for toxigenic C. difficile following clinical cure of the initial CDI episode.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 4 Nov 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Brynjulf Mortensen, pHD study director
Bactolife A/S
4 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Clostridioides Difficile Infection Recurrence, run by Bactolife A/S at 4 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 0 inclusion and 11 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 4 Nov 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 4 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
The proportion of subjects experiencing CDI recurrence in the time period between baseline and end of study follow-up. (time frame: Within the 8 week time period between baseline and end of follow-up). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 4 Nov 2026.