Clinical Trials In Progress

Every scientific research and development, every clinical trial in progress is a glimmer of hope………..HOPE for clinically safe and approved avenues to prevent and treat a
C. difficile infection

Listed below you will find a few examples of  organizations that have active
C. difficile Prevention and Treatment clinical trials in progress.  Click on each organization’s website listed to review their clinical trial study opportunities — Inquire if you or your loved one qualify to participate in their study. 

To Learn More About Clinical Trials — is a registry and results database of publicly and privately supported clinical studies of human participants conducted around the world. Learn more About Clinical Studies and About This Site, including relevant History, Policies, and Laws.  Click on the link below to be redirected to the website:

Clinical Studies Are In Progress To

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Here is a partial-listing and explanations of Clinical Trial Phases:

Clinical trials are conducted in a series of steps, called phases – each phase is designed to answer a separate research question.

  • Phase I: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
  • Phase II: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
  • Phase III: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
  • Phase IV: Studies are done after the drug or treatment has been marketed to gather information on the drug’s effect in various populations and any side effects associated with long-term use.


Visit for a full listing.

  C. diff. Infection (CDI)_Prevention Clinical Studies

Da Volterra is a clinical-stage biotechnology company whose vision is to be a trusted and acknowledged leader in the microbiota field. Da Volterra’s mission is to discover, develop, and bring to market safe and novel therapeutic options, preserving patients’ microbiota to prevent and cure life-threatening diseases. Its most advanced product is DAV132, an oral product to be co-administered with any oral and intravenous antibiotics, to protect patients from antibiotic-induced intestinal microbiota disruption. DAV132 can prevent Clostridioides difficile infection by capturing residual antibiotics in the colon before they can disrupt the intestinal microbiota, without impacting the systemic efficacy of the antibiotics.

 We see DAV132 as a real game-changer for C. difficile prevention.

 Have a look at the DAV132 webpage and video presenting its mechanism of action: 

The video is highly illustrative of what C. diff. is, how C. diff.  is triggered, and how DAV132 could prevent the colonization of the intestinal microbiota by C. diff.  and the occurrence of the infection.

Da Volterra has already performed 6 phase 1 clinical trial with DAV132 in healthy volunteers and one phase 2 clinical trial (SHIELD) in patients demonstrating DAV132 favorable safety profile and mechanism of action. The SHIELD study met its primary endpoint: DAV132 was very safe for use in hospitalized patients with several comorbidities and concomitant medications. The study also demonstrated positive results with regards to biological markers of efficacy for prevention of   C. difficile infection: DAV132 effectively protected the intestinal microbiota of patients from antibiotic-induced disruption and DAV132 also prevented the proliferation of         C. difficile in an ex vivo assay, suggesting that DAV132 is able to protect patients against antibiotic-induced C. difficile infection.

The press release on Da Volterra’s phase 2 SHIELD study results is available here:

 Da Volterra is now preparing for the launch of phase 3 pivotal study of DAV132 in patients who have a high risk of developing Clostridioides difficile infection.

Information on this study is available here:

Pfizer, a leader in vaccine research and innovation, continues to advance its Clostridium difficile (C. difficile) vaccine candidate, PF-06425090. The Phase 3 trial CLOstridium difficile Vaccine Efficacy TRial (CLOVER), is an ongoing placebo-controlled trial designed to assess whether PF-06425090 prevents the disease and whether it is safe and well-tolerated in adults 50 years of age and older. [i], [ii]

Additional information about CLOVER can be found at

i] Clover Trial. Available from: Accessed July 31, 2019.

[ii] Pfizer. Clostridium Difficile Vaccine Efficacy Trial (Clover). [Internet]. [cited 2019 July 31]. Available from: NLM Identifier: NCT03090191.





Seres Therapeutics

“Is another C. diff.  infection getting in the way of your life?”

Most Clostridioides difficile (C. diff) infections occur after antibiotic treatment. Why? Our gut contains trillions of microbes, called the microbiome, which protects us from bacterial invaders that can cause disease. Antibiotics disrupt the microbiome by killing both good and bad bacteria. When the microbiome is damaged, bad bacteria, like C diff, can take advantage and cause disease. Although specific antibiotics can kill the active C diff bacteria, the inactive forms (i.e. C diff spores) are untouched. When the microbiome is disrupted, these spores turn into active C diff bacteria and cause disease again and again – usually after antibiotic treatment has finished.

Seres Therapeutics is developing an investigational microbiome drug called SER-109. This medicine is being developed to prevent C diff from coming back by repairing the microbiome. Seres is pleased to announce the positive top-line results from its ECOSPOR-III trial reported in August 2020. In a placebo-controlled randomized trial of 182 patients with multiple (> 3) recurrent C. diff infection, the recurrence rate was significantly reduced from 41.3% in placebo recipients to 11.1% in the SER-109 recipients. In addition, SER-109 was well tolerated. Based on these encouraging results, Seres is now enrolling an open-label study, in which all participants will receive SER-109. This new study will be open to patients experiencing their first recurrence or multiple recurrences of C. diff at sites in the US and Canada.

On the website, there is a phrase at the bottom stating “Recurrent
C. diff. study now enrolling”. Readers should click on the LEARN MORE icon to get further information on the study.

Vedanta Biosciences, Inc. is a clinical-stage microbiome company developing a new category of therapies for immune-mediated diseases based on rationally-defined consortia of human microbiome-derived bacteria.


VE303 is a defined bacterial consortium designed to prevent recurrent C. difficile infections (“CDI”).  VE303 is a preparation of eight different bacteria that were selected for their presumed ability to prevent the regrowth of C. Difficile.

Why bacterial consortia?

Unlike fecal transplants, which require the use of donors’ stool and are an inherently variable procedure, bacterial consortia therapeutics are defined drug compositions produced from clonally isolated bacteria that can trigger targeted immune responses. And unlike reductionistic approaches such as single strain probiotics, they can robustly shift the gut ecosystem.

The results of the Phase 1 study of VE303 showed both rapid expansion of protective VE303 bacteria in the gut and accelerated recovery to a healthy microbiome after disruption to the normal microbiome in the gut caused by antibiotics.  Based on these Phase 1 results, Vedanta is now evaluating VE303 (the “CONSORTIUM” study) in individuals with CDI to see if it can prevent future CDI recurrences by restoring the intestinal bacteria to a healthy state.


CONSORTIUM (NCT03788434) is a randomized, double-blind placebo-controlled Phase 2 study to evaluate the safety, tolerability, pharmacokinetic/pharmacodynamic (PK/PD), and efficacy of VE303 in patients with a recent diagnosis of CDI, who have completed a course of antibiotics but remain at risk for recurrence. The primary endpoint will be the prevention of infection recurrence at eight weeks.

CONSORTIUM is currently enrolling participants across North America (U.S. and Canada) who have been diagnosed with high-risk CDI.

For additional study information or to locate a study site near you, please visit

Artugen Therapeutics

Artugen is developing a novel oral Live Biotherapeutic Product for the prevention of C. difficile infection recurrence. The investigational drug, ART24 capsules, is composed of freeze-dried gut-derived bacteria called Bacillus amyloliquefaciens which acts directly against the C. difficile bacteria. ART24-1-001 is a blinded study for people with a recent C. difficile infection (first episode or recurrent infection). The study is to see how well ART24 is tolerated and how well ART24 can help prevent future episodes of C. difficile infection compared with placebo.

You may be eligible to participate in ART24-1-001 if you meet these criteria*:

  • Greater than or equal to 18 years of age
  • Currently taking or have recently finished (within the last 6 days) taking antibiotics for a
    C. difficile infection
  • Do not have inflammatory bowel disease (IBD)

*Other criteria will also apply.

All eligible participants will receive:

  • ART24 or placebo
  • Study-related medication and exams at no cost
  • Compensation for reasonable travel and meal expenses

This study is currently recruiting in the following areas: Butte (MT), Riverton (UT), Shreveport (LA), Doral (FL), Hillsborough (NJ), Bronx (NY), New York (NY), Massapequa (NY/Long Island), Palm Springs (CA), and Boston (MA).

To learn more or join the study please go to and click on More Information.

C. diff. Infection (CDI) Treatment – Clinical Studies

.Acurx Pharmaceuticals is a privately held, clinical-stage biopharmaceutical company developing a new class of antibiotics for infections caused by bacteria listed as priority pathogens by the World Health Organization, Centers for Disease Control and Prevention, and Food and Drug Administration.

Ibezapolstat (formerly named ACX-362E) is our lead antibiotic candidate.  Ibezapolstat is a first-in-class of a new class of Pol IIIC inhibitors which is in clinical development to treat
C. difficile infections or CDI.  Current treatments for CDI infections utilize other mechanisms of action while ibezapolstat is the first antibiotic candidate intended to work by blocking the Pol IIIC enzyme in C. difficile.  This enzyme is necessary for the replication of the DNA of the bacterial cell.

Acurx has worked closely with the FDA to obtain FDA “Fast track” designation as well as the designation of ibezapolstat as a qualified infectious disease product, or QIDP, which provides incentives through the GAIN Act including priority review by the FDA, “fast-track” eligibility, and extension of statutory exclusivity periods in the U.S. for an additional 5 years upon FDA marketing approval of the product to treat patients with CDI.

Acurx acquired the worldwide rights to ibezapolstat from GLSynthesis Inc. in February 2018.

Ibezapolstat is active against the GAIN Pathogen Clostridium difficile

C. difficile, or CDI, is a pathogen listed in the GAIN Act as a pathogen that causes serious or life-threatening infections and the CDC identifies CDI as an urgent need in terms of generating new antibiotics to treat these infections.

The GAIN Act, Title VIII (Sections 801 through 806) of the FDA Safety and Innovation Act, seeks to provide pharmaceutical and biotechnology companies with incentives to encourage the development of new drugs to treat, prevent, detect and diagnose antibiotic-resistant infections. Qualifying pathogens are defined by the GAIN Act to include multi-drug resistant Gram-negative bacteria, including PseudomonasAcinetobacterKlebsiella, and Escherichia coli species; resistant Gram-positive pathogens, including methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Staphylococcus aureus, and vancomycin-resistant Enterococcus (VRE); multi-drug resistant tuberculosis; and Clostridium difficile. It extends the length of time an approved drug is free from competition and clarifies the regulatory pathway for new antibiotics.

For more information, please visit the website at

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DEINOVE is a French biotechnology company, a leader in disruptive innovation, which aims to help meet the challenges of antibiotic resistance and the transition to a sustainable production model for the nutrition and cosmetics industries.

DEINOVE has developed unique and comprehensive expertise in the field of rare bacteria that it can decipher, culture, and optimize to disclose unsuspected possibilities and induce them to produce biobased molecules with activities of interest on an industrial scale. To do so, DEINOVE has been building and documenting since its creation an unparalleled biodiversity bank that it exploits thanks to a unique technological platform in Europe.

This trial is concentrated in the United States. It will take place in two stages:

  • In the first phase, involving 5 centers, a cohort of 10 patients with moderate to severe CDI will be treated with DNV3837. At the end of this phase, the DSMB*** will review the interim results.
  • The second phase will involve 30 patients with severe CDI and will be carried out in 15 investigation centers. This will be an open-label randomized trial testing DNV3837 (in 2/3 of patients) against an approved standard of care**** (1/3 of patients) for comparison purposes.

The results of this clinical trial should be available by the end of 2020.

 “The start of this Phase II clinical trial is a significant step forward for DEINOVE and a great hope for patients. We are very proud to provide a potential solution to this unmet medical need and, to this end, work with the best American specialists in this area. The investigation centers are very committed to conducting this trial which, in the event of positive results, will be an important milestone towards the registration of DNV3837,” said Dr. Georges Gaudriault, Scientific Director of DEINOVE.

This multicentric open-label trial will be conducted both in Germany and the United States. Under the updated protocol, the number of sites, necessary for the implementation of its Phase II, has been reached. The inclusion of the first patient is planned for mid-2019. Medpace (Nasdaq: MEDP) was chosen as the Clinical Research Organization to oversee the trial.

In parallel, DEINOVE has started the production of the first DNV3837 batch on a commercial scale, following good manufacturing practices. This batch will be used to prepare enough material for conducting Phase III trial. CMC (Chemistry, Manufacturing, and Controls) operations in the United States have been contracted to a recognized CMO and the first production steps have been completed per the agreed specifications.

For more information: 

Rebiotix Inc., a Ferring Company, is a clinical-stage biotechnology company founded to revolutionize the treatment of debilitating diseases by harnessing the power of the human microbiome.

It is increasingly recognized that the restoration of healthy gut microbiota is necessary for the effective treatment of a large number of challenging diseases.


The PUNCH CD3-OLS study is a Phase 3 clinical study to assess the safety and tolerability of Rebiotix RBX2660 for the prevention of recurrent Clostridium difficile infection (CDI) in a recurrent CDI population that is broader and more inclusive than that included in prior studies using RBX2660.

This open-label study is expected to enroll up to 200 patients at 80 research sites in the U.S. and Canada. Patients that meet the study requirements and choose to enroll will receive RBX2660, an investigational new drug (no placebo). Study patients whose CDI returns within 8 weeks after study treatment may be scheduled to receive additional RBX2660 treatment. The study’s primary objective is to assess the safety and tolerability of RBX2660 through 6 months after the final RBX2660 study treatment.

Additional information can be found  on the website

Or through the Rebiotix website:

 Rebiotix has a diverse pipeline of investigational drug products built on its pioneering microbiota-based MRT drug platform. The MRT platform is a standardized, stabilized drug technology that is designed to rehabilitate the human microbiome by delivering a broad consortium of live microbes into a patient’s intestinal tract. The lead drug candidate, RBX2660, is currently in Phase 3 clinical development for the prevention of recurrent Clostridium difficile(C. diff) infection. RBX2660 has been granted Fast Track status, Orphan Drug, and Breakthrough Therapy designation from the US FDA for its potential to prevent recurrent C. diff infection. Rebiotix’s clinical pipeline also features RBX7455, a lyophilized, non-frozen, oral capsule part of a recently completed investigator-sponsored Phase 1 trial for the prevention of recurrent C. diff infection. For more information on Rebiotix and its pipeline of human microbiome-directed therapies for diverse disease states, visit

About Ferring Pharmaceuticals:   Ferring Pharmaceuticals is a research-driven biopharmaceutical company devoted to identifying, developing, and marketing innovative products in the fields of reproductive health, women’s health, urology, gastroenterology, endocrinology, oncology, and orthopedics. For more information,  visit

Summit Therapeutics  Ridinilazole is being developed by Summit Therapeutics as a potential treatment for    C. difficile infection (CDI). It’s a new antibiotic, and Summit is testing whether it can improve patient outcomes over the current standard of care, vancomycin, in two global clinical trials. In an earlier clinical trial in patients with CDI, ridinilazole was found to be superior to vancomycin in a measure called a sustained clinical response, which tested if patients were cured after treatment and did not experience a recurrence within 30-days post-treatment. More information on ridinilazole can be found by visiting

Some key information about the trials:

  • Each trial is expected to enroll up to 680 patients
  • Patients will be randomized to receive either ridinilazole or vancomycin, and neither the patients nor the study doctors will know which drug they receive
  • Participation will involve about 7 study visits over approximately 100 days to track the safety and effectiveness of each drug
  • Patients who participate may be reimbursed for travel expenses associated with study site visits
  • Patients must be 18 years of age or older
  • Patients must have signs and symptoms of CDI, including diarrhea, in the 24 hours before entry in the trial and a positive toxin test on a stool sample produced within 72 hours of entry into the trial
  • Patients cannot have had more than one prior episode of CDI in the previous three months or more than three episodes in the past 12 months
  • Patients cannot have had more than 24 hours of CDI antibiotic treatment before entry into the trial
  • There are additional entry criteria and considerations; the study doctors will ultimately decide whether a patient is eligible for entry into the clinical trials and the patient will be required to give consent

Further details of the global clinical trials can be found by visiting: and

ridinilazole has already received Qualified Infectious Disease Product, or QIDP, designation and has been granted Fast Track status from the US Food and Drug Administration

To learn more about ridinilazole and Summit Therapeutics, click on the following link

to be redirected to the Summit Therapeutics website:

The PRISM 3 clinical study is for patients who have had a recurrence of Clostridium difficile infection (CDI or C. diff). The study is evaluating the safety and effectiveness of the study drug (CP101) to prevent the recurrence of CDI compared to a placebo. The study is currently enrolling across the United States. This clinical trial (CP101) is in Phase 2.  For more information from  click on the following link:

The study drug, CP101, is a Full-Spectrum Microbiota investigational drug designed to deliver bacteria to the intestine. This bacteria may help overtake the surplus of C. diff. bacteria that cause CDI.CP101 is encapsulated for oral administration. The powder is intended to be released from the capsules in the right part of your intestine where the bacteria may repopulate. This may aid in restoring the diverse community of bacteria found in the healthy human gut, which may prevent the recurrence of C. diff…
Click here to learn more about PRISM 3 ( and see if there is a study near you and if you are eligible.

Crestone is developing a novel antibiotic known as CRS3123 for treatment of C. difficile infection, or CDI.  In preclinical (early) studies CRS3123 has demonstrated that it quickly halts production of C. difficile toxin and spores via a new mechanism of action.  In Phase 1 human clinical trials it caused minimal disruption of other, normal gut bacteria.  In this Phase 2 study sponsored by NIAID (NIH), Crestone will test two different doses of CRS3123 compared to a standard antibiotic treatment for this infection called vancomycin.

If enrolled, subjects will receive either, 400 mg or 800 mg of CRS3123 or vancomycin for 10 days.  Doses will be taken by mouth, every 6 hours. Neither subjects nor study healthcare providers will know which drug is being administered.  Then subjects will be followed for an additional 60 days, resulting in about eight outpatient study visits over 70 days.  Participants will receive study-related medication and exams at no cost and may be reimbursed for travel expenses for study visits.

The study will enroll subjects 18 or older who have a primary episode or first recurrence of CDI, including diarrhea in the last 24 hours and a positive C. difficile toxin test on a stool sample.  They may not participate if they have had more than one CDI episode in the last three months (or one that was not initially responsive to vancomycin), or two CDI episodes in the past twelve months.  Pregnant or breastfeeding women may not participate in this study, and other entry criteria apply.  Study physicians will determine eligibility and then request subjects’ consent to participate.

This study is currently recruiting in the following areas: Sacramento, CA; Lancaster, CA; Calgary, AB CANADA; London, ON CANADA; St. Petersburg, FL; Miami Lakes, FL; Pompano Beach, FL; Miami, FL; Doral, FL; Idaho Falls, ID; Shreveport, LA; Rochester, MN; Omaha, NE; Mentor, OH; Toledo, OH; Uniontown, PA; Union City, TN; San Antonio, TX; Cedar Park, TX; Houston, TX; Seattle, WA.

To learn more, please visit Crestone’s website



“The C Diff Foundation’s mission is to educate and advocate for Clostridium difficile infection prevention, treatments, support, and environmental safety worldwide.
The C Diff Foundation’s organization is comprised of 100% volunteering members who are dedicated to our mission and adhere to the Foundation’s Code of Ethics
which prohibits the endorsement and paid promotion of products, services, medications, or clinical studies in progress. All website entries, public presentations, and workshops are to raise C. diff. infection awareness in all areas of the C Diff Foundation’s mission statement, including, and not limited to, infection prevention, sepsis, healthcare-associated infections, antimicrobial resistance, antibiotic stewardship and provide education on all the above.”