• Skip to primary navigation
  • Skip to main content
Rebiotix Logo

Rebiotix

Powerful Therapy Delivered

  • Home
  • About
    • Senior Management
    • Stool Donor Program
    • Careers and Employment
  • Our Therapy
    • The Human Microbiome
    • Microbiota Restoration Therapy
    • Clostridioides difficile Infection
    • The Future of Microbiome-Based Therapeutics
  • Clinical Trials
    • RBX2660 Clinical Trials
    • RBX7455 Clinical Evaluation
    • Physician-sponsored Studies
    • Patient Resources
    • Expanded Access Policy
  • Science
    • Congress Publications
    • Manuscripts and Whitepapers
    • Related Evidence
  • Media
    • Latest Press Releases
    • Frequently Asked Questions
    • “Rebiotix” in the News
    • Conferences
    • Media Tools
    • Presentations & Videos
    • Contacts
  • Contact Us
  • Show Search
Hide Search

Response to Microbiota-Based Drug RBX2660 is Associated with Reduction in Antimicrobial Resistance Genes in Patients with Recurrent Clostridioides difficile Infections

Julia Garcia-Diaz MD, Courtney Jones, Hiren Karathia PhD, Brian Fanelli, Nur A Hasan PhD, Ken Blount PhD

Download this poster (341 KB)

ASM Microbe 2019
June 20-24, 2019, San Francisco, CA

Background

  • Antibiotic microbial resistance (AMR) is a global health challenge, and is common in recurrent Clostridioides difficile infection (rCDI) population due to high historical exposure to antibiotics.
  • The gut microbiota implicated as a reservoir of AMR bacteria.
  • Therapeutic approaches that decolonize AMR gut bacteria would be valuable.
  • In a previous analysis, RBX2660, an investigational standardized microbiota-restoration therapy in clinical development for preventing rCDI decreased vancomycin-resistant enterococci colonization.
  • Herein, we assessed the total AMR gene profile before and after treatment in fecal samples from RBX2660 treatment responders in a Phase 2 rCDI trial.

Methods

  • PUNCH Open Label™ (NCT02589847) – prospective, multicenter, open-label Phase 2 study assessing the efficacy and safety of RBX2660 treatment of recurrent CDI.
    • PATIENT POPULATION: multi-recurrent CDI (≥ 2 recurrent episodes at enrollment)
    • TREATMENT: two doses of RBX2660 administered 7 ± 2 days apart
    • EFFICACY: absence of CDI recurrence at 8 weeks after last study treatment
    • FAILURE: documented recurrence, including positive laboratory diagnosis for C. difficile
    • CONTROL GROUP: historical chart review of patients who only received antibiotic therapy for rCDI
  • Analysis included 66 longitudinally matched samples from 22 treatment responsive participants, including before treatment (BL) and 7 ± 3 and 30 ± 10 days after treatment. Sample set represents 17 trial sites from US and Canada.
  • All samples were frozen without stabilizers after collection, extracted, and sequenced using a shallow shotgun method.
  • Sequencing reads were compared to a proprietary database of gene sequences annotated as related to antimicrobial resistance (CosmosID)
  • ≥ 40% sequencing coverage of an AMR gene was considered positive identification in each sample.
  • AMR gene coverage for participant samples were compared to Human Microbiome Project (HMP) data for which comparable sequencing depth was simulated.

RBX2660 is Efficacious & Durable

  • 119 of 149 RBX2660-treated participants (80%) were responders at 8 weeks after treatment
  • 57 of 110 patients (52%) in the historical control group were recurrence free 8 weeks after antibiotic treatment
  • Only 3 of 109 evaluable primary RBX2660 responders reported reinfection at 6 months
  • 97% of RBX2660-treated 8-week responders who were evaluable at 6 months remained recurrence free
  • Follow up ongoing to 24 months

RBX2660 Shifts Microbiome Composition

  • Participants were dysbiotic at study entry, with decreased Bacteroidia and Clostridia and overabundance of Gammaproteobacteria and Bacilli
  • Bacteroidia, Clostridia increased and Gammaproteobacteria, Bacilli decreased after treatment; durable to 6 months after treatment
  • Based on shallow-shotgun sequencing data

Antimicrobial Resistance Genes (AMR) Analysis

  • Prior to treatment (BL) rCDI participants had significantly higher abundance of antimicrobial resistance (AMR) genes than the HMP healthy population
  • After treatment (7 and 30 days), participants’ had decreased AMR gene abundance, not significantly different from HMP

Conclusions

  • In a Phase 2 open label trial, RBX2660 was 80% effective for preventing rCDI, with durable response to at least 6 months.
  • Responding participants’ microbiomes resolved toward a healthier composition after treatment.
  • In a 22-participant subgroup analysis, there was a significant decrease in antimicrobial resistance genes from before to after successful response to RBX2660.

Microbiota Restoration Therapy Posters Posters

Interested in Becoming a Stool Donor? Learn More

Rebiotix

  • Copyright © 2022 Rebiotix, Inc.
  • A Ferring Company
  • Privacy Policy
  • Terms of Use
  • Sitemap
  • Contact Us

We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. By clicking “Accept”, you consent to the use of ALL the cookies.
Cookie settingsACCEPT
Manage consent

Privacy Overview

This website uses cookies to improve your experience while you navigate through the website. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience.
Necessary
Always Enabled
Necessary cookies are absolutely essential for the website to function properly. These cookies ensure basic functionalities and security features of the website, anonymously.
CookieDurationDescription
cookielawinfo-checbox-analytics11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Analytics".
cookielawinfo-checbox-functional11 monthsThe cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional".
cookielawinfo-checbox-others11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other.
cookielawinfo-checkbox-necessary11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookies is used to store the user consent for the cookies in the category "Necessary".
cookielawinfo-checkbox-performance11 monthsThis cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Performance".
viewed_cookie_policy11 monthsThe cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. It does not store any personal data.
Functional
Functional cookies help to perform certain functionalities like sharing the content of the website on social media platforms, collect feedbacks, and other third-party features.
Performance
Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors.
Analytics
Analytical cookies are used to understand how visitors interact with the website. These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc.
Advertisement
Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. These cookies track visitors across websites and collect information to provide customized ads.
Others
Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet.
SAVE & ACCEPT