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Fitzpatrick F, Brennan R, van Prehn J, Skally M, Brady M, Burns K, Rooney C, Wilcox MH. European Practice for CDI Treatment. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1435:57-84. [PMID: 38175471 DOI: 10.1007/978-3-031-42108-2_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Clostridioides difficile infection (CDI) remains a significant cause of morbidity and mortality worldwide. Historically, two antibiotics (metronidazole and vancomycin) and a recent third (fidaxomicin) have been used for CDI treatment; convincing data are now available showing that metronidazole is the least efficacious agent. The European Society of Clinical Microbiology and Infectious Diseases (ESCMID) management guidance for CDI were updated in 2021. This guidance document outlines the treatment options for a variety of CDI clinical scenarios and for non-antimicrobial management (e.g., faecal microbiota transplantation, FMT). One of the main changes is that metronidazole is no longer recommended as first-line CDI treatment. Rather, fidaxomicin is preferred on the basis of reduced recurrence rates with vancomycin as an acceptable alternative. Recommended options for recurrent CDI now include bezlotoxumab as well as FMT.A 2017 survey of 20 European countries highlighted variation internationally in CDI management strategies. A variety of restrictions were in place in 65% countries prior to use of new anti-CDI treatments, including committee/infection specialist approval or economic review/restrictions. This survey was repeated in November 2022 to assess the current landscape of CDI management practices in Europe. Of 64 respondents from 17 countries, national CDI guidelines existed in 14 countries, and 11 have already/plan to incorporate the ESCMID 2021 CDI guidance, though implementation has not been surveyed in 6. Vancomycin is the most commonly used first-line agent for the treatment of CDI (n = 42, 66%), followed by fidaxomicin (n = 30, 47%). Six (9%) respondents use metronidazole as first-line agent for CDI treatment, whereas 22 (34%) only in selected low-risk patient groups. Fidaxomicin is more likely to be used in high-risk patient groups. Availability of anti-CDI therapy influenced prescribing in six respondents (9%). Approval pre-prescription was required before vancomycin (n = 3, 5%), fidaxomicin (n = 10, 6%), bezlotoxumab (n = 11, 17%) and FMT (n = 10, 6%). Implementation of CDI guidelines is rarely audited.Novel anti-CDI agents are being evaluated; it is not yet clear what will be the roles of these agents. The treatment of recurrent CDI is particularly troublesome, and several different live biotherapeutics are being developed, in addition to FMT.
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Affiliation(s)
- Fidelma Fitzpatrick
- Department of Clinical Microbiology, The Royal College of Surgeons in Ireland, Dublin, Ireland.
- Department of Clinical Microbiology, Beaumont Hospital, Dublin, Ireland.
| | - Robert Brennan
- Department of Clinical Microbiology, The Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Joffrey van Prehn
- Department of Medical Microbiology, Leiden University Medical Center, Leiden, the Netherlands
| | - Mairead Skally
- Department of Clinical Microbiology, The Royal College of Surgeons in Ireland, Dublin, Ireland
- Department of Clinical Microbiology, Beaumont Hospital, Dublin, Ireland
| | - Melissa Brady
- Health Protection Surveillance Centre (HPSC), Dublin, Ireland
| | - Karen Burns
- Department of Clinical Microbiology, Beaumont Hospital, Dublin, Ireland
| | - Christopher Rooney
- Microbiology, Leeds Teaching Hospitals, Leeds, UK
- University of Leeds, Leeds, UK
| | - Mark H Wilcox
- University of Leeds, Leeds, UK.
- Leeds Teaching Hospitals and Leeds Regional Public Health Laboratory, UK Health Security Agency (UKHSA), Leeds, UK.
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Butler MS, Henderson IR, Capon RJ, Blaskovich MAT. Antibiotics in the clinical pipeline as of December 2022. J Antibiot (Tokyo) 2023; 76:431-473. [PMID: 37291465 PMCID: PMC10248350 DOI: 10.1038/s41429-023-00629-8] [Citation(s) in RCA: 101] [Impact Index Per Article: 50.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 04/20/2023] [Accepted: 04/25/2023] [Indexed: 06/10/2023]
Abstract
The need for new antibacterial drugs to treat the increasing global prevalence of drug-resistant bacterial infections has clearly attracted global attention, with a range of existing and upcoming funding, policy, and legislative initiatives designed to revive antibacterial R&D. It is essential to assess whether these programs are having any real-world impact and this review continues our systematic analyses that began in 2011. Direct-acting antibacterials (47), non-traditional small molecule antibacterials (5), and β-lactam/β-lactamase inhibitor combinations (10) under clinical development as of December 2022 are described, as are the three antibacterial drugs launched since 2020. Encouragingly, the increased number of early-stage clinical candidates observed in the 2019 review increased in 2022, although the number of first-time drug approvals from 2020 to 2022 was disappointingly low. It will be critical to monitor how many Phase-I and -II candidates move into Phase-III and beyond in the next few years. There was also an enhanced presence of novel antibacterial pharmacophores in early-stage trials, and at least 18 of the 26 phase-I candidates were targeted to treat Gram-negative bacteria infections. Despite the promising early-stage antibacterial pipeline, it is essential to maintain funding for antibacterial R&D and to ensure that plans to address late-stage pipeline issues succeed.
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Affiliation(s)
- Mark S Butler
- Centre for Superbug Solutions, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, 4072, Australia.
| | - Ian R Henderson
- Centre for Superbug Solutions, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, 4072, Australia
| | - Robert J Capon
- Centre for Superbug Solutions, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, 4072, Australia
| | - Mark A T Blaskovich
- Centre for Superbug Solutions, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, 4072, Australia.
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3
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Khanna S, Voth E. Therapeutics for Clostridioides difficile infection: molecules and microbes. Expert Rev Gastroenterol Hepatol 2023; 17:903-911. [PMID: 37606962 DOI: 10.1080/17474124.2023.2250716] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 07/11/2023] [Accepted: 08/18/2023] [Indexed: 08/23/2023]
Abstract
INTRODUCTION Clostridioides difficile infection (CDI) is a major healthcare problem in the developed world, and effective management of recurrent infection remains one of the biggest challenges. Several advances have occurred in the management of CDI, and in the last 15 years, multiple new agents have been tested. Since 2011, four new products have been approved by the US FDA for treatment of CDI or prevention of recurrent CDI. AREAS COVERED This review focuses on therapeutics of CDI and includes sections on primary prevention, management of active infection, and prevention of recurrent CDI. Specifically, data are included on fecal microbiota transplantation and live biotherapeutics. A comprehensive search of several databases including Ovid MEDLINE(R) and Epub Ahead of Print, In-Process & Other Non-Indexed Citations, and Daily, Ovid EMBASE, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews, and Scopus from inception to 1 May 2023 was conducted. EXPERT OPINION Metronidazole is no longer advised for management of outpatient CDI. The preferred medication of choice for a first episode is oral vancomycin or fidaxomicin. For those patients who recur after the first episode, vancomycin taper pulse or fidaxomicin can be used. Intravenous bezlotoxumab, a monoclonal antibody, is available to prevent recurrences. There are now two FDA-approved microbiome-based therapies or live biotherapeutics for prevention of recurrent CDI, for any recurrent CDI and not necessarily multiply recurrent C difficile. Fecal microbiota transplantation remains available in limited settings for recurrent CDI.
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Affiliation(s)
- Sahil Khanna
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA
| | - Elida Voth
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA
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4
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Yip C, Phan JR, Abel-Santos E. Mechanism of germination inhibition of Clostridioides difficile spores by an aniline substituted cholate derivative (CaPA). J Antibiot (Tokyo) 2023; 76:335-345. [PMID: 37016015 PMCID: PMC10406169 DOI: 10.1038/s41429-023-00612-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 02/28/2023] [Accepted: 03/07/2023] [Indexed: 04/06/2023]
Abstract
Clostridioides difficile infection (CDI) is the major identifiable cause of antibiotic-associated diarrhea and has been declared an urgent threat by the CDC. C. difficile forms dormant and resistant spores that serve as infectious vehicles for CDI. To cause disease, C. difficile spores recognize taurocholate and glycine to trigger the germination process. In contrast to other sporulating bacteria, C. difficile spores are postulated to use a protease complex, CspABC, to recognize its germinants. Since spore germination is required for infection, we have developed anti-germination approaches for CDI prophylaxis. Previously, the bile salt analog CaPA (an aniline-substituted cholic acid) was shown to block spore germination and protect rodents from CDI caused by multiple C. difficile strains and isolates. In this study, we found that CaPA is an alternative substrate inhibitor of C. difficile spore germination. By competing with taurocholate for binding, CaPA delays C. difficile spore germination and reduces spore viability, thus diminishing the number of outgrowing vegetative bacteria. We hypothesize that the reduction of toxin-producing bacterial burden explains CaPA's protective activity against murine CDI. Previous data combined with our results suggests that CaPA binds tightly to C. difficile spores in a CspC-dependent manner and irreversibly traps spores in an alternative, time-delayed, and low yield germination pathway. Our results are also consistent with kinetic data suggesting the existence of at least two distinct bile salt binding sites in C. difficile spores.
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Affiliation(s)
- Christopher Yip
- Department of Chemistry and Biochemistry, University of Nevada, Las Vegas, NV, 89154, USA
| | - Jacqueline R Phan
- Department of Chemistry and Biochemistry, University of Nevada, Las Vegas, NV, 89154, USA
| | - Ernesto Abel-Santos
- Department of Chemistry and Biochemistry, University of Nevada, Las Vegas, NV, 89154, USA.
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Rep V, Štulić R, Koštrun S, Kuridža B, Crnolatac I, Radić Stojković M, Paljetak HČ, Perić M, Matijašić M, Raić-Malić S. Novel tetrahydropyrimidinyl-substituted benzimidazoles and benzothiazoles: synthesis, antibacterial activity, DNA interactions and ADME profiling. RSC Med Chem 2022; 13:1504-1525. [PMID: 36561067 PMCID: PMC9749923 DOI: 10.1039/d2md00143h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 07/12/2022] [Indexed: 12/25/2022] Open
Abstract
A series of tetrahydropyrimidinyl-substituted benzimidazoles attached to various aliphatic or aromatic residues via phenoxymethylene were synthesised to investigate their antibacterial activities against selected Gram-positive and Gram-negative bacteria. The influence of the type of substituent at the C-3 and C-4 positions of the phenoxymethylene linker on the antibacterial activity was observed, showing that the aromatic moiety improved the antibacterial potency. Of all the evaluated compounds, benzoyl-substituted benzimidazole derivative 15a was the most active compound, particularly against the Gram-negative pathogens E. coli (MIC = 1 μg mL-1) and M. catarrhalis (MIC = 2 μg mL-1). Compound 15a also exhibited the most promising antibacterial activity against sensitive and resistant strains of S. pyogenes (MIC = 2 μg mL-1). Significant stabilization effects and positive induced CD bands strongly support the binding of the most biologically active benzimidazoles inside the minor grooves of AT-rich DNA, in line with docking studies. The predicted physico-chemical and ADME properties lie within drug-like space except for low membrane permeability, which needs further optimization. Our findings encourage further development of novel structurally related 5(6)-tetrahydropyrimidinyl substituted benzimidazoles in order to optimize their antibacterial effect against common respiratory pathogens.
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Affiliation(s)
- Valentina Rep
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of ZagrebMarulićev trg 1910000 ZagrebCroatia
| | - Rebeka Štulić
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of ZagrebMarulićev trg 1910000 ZagrebCroatia
| | - Sanja Koštrun
- Selvita d.o.oPrilaz baruna Filipovića 2910000 ZagrebCroatia
| | - Bojan Kuridža
- Ruđer Bošković Institute, Division of Organic Chemistry and BiochemistryBijenička cesta 5410000 ZagrebCroatia
| | - Ivo Crnolatac
- Ruđer Bošković Institute, Division of Organic Chemistry and BiochemistryBijenička cesta 5410000 ZagrebCroatia
| | - Marijana Radić Stojković
- Ruđer Bošković Institute, Division of Organic Chemistry and BiochemistryBijenička cesta 5410000 ZagrebCroatia
| | - Hana Čipčić Paljetak
- Department for Intercellular Communication, Center for Translational and Clinical Research, University of Zagreb School of MedicineŠalata 210000 ZagrebCroatia
| | - Mihaela Perić
- Department for Intercellular Communication, Center for Translational and Clinical Research, University of Zagreb School of MedicineŠalata 210000 ZagrebCroatia
| | - Mario Matijašić
- Department for Intercellular Communication, Center for Translational and Clinical Research, University of Zagreb School of MedicineŠalata 210000 ZagrebCroatia
| | - Silvana Raić-Malić
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of ZagrebMarulićev trg 1910000 ZagrebCroatia
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Collins DA, Riley TV. Ridinilazole: a novel, narrow-spectrum antimicrobial agent targeting Clostridium (Clostridioides) difficile. Lett Appl Microbiol 2022; 75:526-536. [PMID: 35119124 PMCID: PMC9541751 DOI: 10.1111/lam.13664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 01/12/2022] [Accepted: 01/31/2022] [Indexed: 11/26/2022]
Abstract
Clostridium (Clostridioides) difficile infection (CDI) remains an urgent threat to patients in health systems worldwide. Recurrent CDI occurs in up to 30% of cases due to sustained dysbiosis of the gut microbiota which normally protects against CDI. Associated costs of initial and recurrent episodes of CDI impose heavy financial burdens on health systems. Vancomycin and metronidazole have been the mainstay of therapy for CDI for many years; however, these agents continue to cause significant disruption to the gut microbiota and thus carry a high risk of recurrence for CDI patients. Treatment regimens are now turning towards novel narrow spectrum antimicrobial agents which target C. difficile while conserving the commensal gut microbiota, thus significantly reducing risk of recurrence. One such agent, fidaxomicin, has been in therapeutic use for several years and is now recommended as a first-line treatment for CDI, as it is superior to vancomycin in reducing risk of recurrence. Another narrow spectrum agent, ridnilazole, was recently developed and is undergoing evaluation of its potential clinical utility. This review aimed to summarize experimental reports of ridinilazole and assess its potential as a first-line agent for treatment of CDI. Reported results from in vitro assessments, and from hamster models of CDI, show potent activity against C. difficile, non-inferiority to vancomycin for clinical cure and non-susceptibility among most gut commensal bacteria. Phase I and II clinical trials have been completed with ridinilazole showing high tolerability and efficacy in treatment of CDI, and superiority over vancomycin in reducing recurrence of CDI within 30 days of treatment completion. Phase III trials are currently underway, the results of which may prove its potential to reduce recurrent CDI and lessen the heavy health and financial burden C. difficile imposes on patients and healthcare systems.
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Affiliation(s)
- Deirdre A Collins
- School of Medical and Health SciencesEdith Cowan UniversityJoondalupWesternAustralia
| | - Thomas V. Riley
- School of Medical and Health SciencesEdith Cowan UniversityJoondalupWesternAustralia
- Department of MicrobiologyPathWest Laboratory MedicineNedlandsWesternAustralia
- Medical, Molecular and Forensic SciencesMurdoch UniversityMurdochWestern AustraliaAustralia
- School of Biomedical SciencesThe University of Western AustraliaQueen Elizabeth II Medical CentreNedlandsWAAustralia
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7
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In Vitro and In Vivo Antibacterial Activities of a Novel Quinolone Compound, OPS-2071, against Clostridioides difficile. Antimicrob Agents Chemother 2021; 65:AAC.01170-20. [PMID: 33495229 PMCID: PMC8097418 DOI: 10.1128/aac.01170-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 12/25/2020] [Indexed: 02/06/2023] Open
Abstract
OPS-2071 is a novel quinolone antibacterial agent characterized by low oral absorption that reduces the risk of adverse events typical of fluoroquinolone class antibiotics. The in vitro and in vivo antibacterial activities of OPS-2071 against Clostridioides difficile were evaluated in comparison to vancomycin and fidaxomicin. OPS-2071 is a novel quinolone antibacterial agent characterized by low oral absorption that reduces the risk of adverse events typical of fluoroquinolone class antibiotics. The in vitro and in vivo antibacterial activities of OPS-2071 against Clostridioides difficile were evaluated in comparison to vancomycin and fidaxomicin. OPS-2071 exhibited potent antibacterial activity against 54 clinically isolated C. difficile strains with a MIC of 0.125 μg/ml (MIC50) and 0.5 μg/ml (MIC90), making it more active than vancomycin on a concentration basis (MIC50, 2 μg/ml; MIC90, 4 μg/ml) and comparable to fidaxomicin (MIC50, 0.063 μg/ml; MIC90, 8 μg/ml). OPS-2071 showed equally potent antibacterial activity against both hypervirulent and nonhypervirulent strains, while a significant difference in susceptibility to fidaxomicin was observed. Spontaneous resistance to OPS-2071 and vancomycin was not observed; however, resistance to fidaxomicin was observed at 4× MIC. The mutant prevention concentration of OPS-2071 was 16-fold lower than those of fidaxomicin and vancomycin, and the postantibiotic effect of OPS-2071 was longer than those of fidaxomicin and vancomycin. Also, OPS-2071 showed low systemic exposure, with OPS-2071 having 2.9% oral bioavailability at 1 mg/kg in rats. Furthermore, OPS-2071 showed significant in vivo efficacy at 0.0313 mg/kg/day (50% effective doses), 39.0-fold and 52.1-fold lower than those of vancomycin and fidaxomicin, respectively, in a hamster model of C. difficile infection. OPS-2071 has the potential to become a new therapeutic option for treating C. difficile infection.
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8
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Dutta D, Jafri F, Stuhr D, Knoll BM, Lim SH. A contemporary review of Clostridioides difficile infections in patients with haematologic diseases. J Intern Med 2021; 289:293-308. [PMID: 32910532 DOI: 10.1111/joim.13173] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 08/18/2020] [Indexed: 12/14/2022]
Abstract
Clostridioides (Clostridium) difficile (C. difficile) infection is one of the most common causes of increased morbidity and mortality. Approximately 500 000 C. difficile infections (CDIs) occur each year in the United States, and they result in more than 29 000 deaths. Patients with haematologic diseases are at a higher risk for this infection due to frequent hospitalization and exposure to treatment-associated risk factors. Whilst several currently available antimicrobial agents offer resolution, recurrence of infection remains a major concern. Recent advancement in deciphering C. difficile virulence mechanisms and identification of its allies in contributing to the infection has led to the development of alternative treatment strategies. Here, we will provide a contemporary discussion of how major risk factors in haematologic diseases, such as immunosuppression, chemoradiation, use of antibiotic, proton pump inhibitor and opioid, and deficiency in butyrate and antimicrobial peptides contribute to C. difficile infection. Next, we will highlight different approaches to control and mitigate this infection such as antibiotic stewardship and faecal microbiota transplantation. Finally, we will explore several emerging treatments such as use of pre- and probiotics, immunotherapy and microbiome-sparing agents.
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Affiliation(s)
- D Dutta
- From the, Division of Hematology and Oncology, State University of New York Downstate Health Sciences University, Brooklyn, NY, USA.,Division of Hematology and Oncology, New York Medical College, Valhalla, NY, USA
| | - F Jafri
- Department of Medicine, New York Medical College, Valhalla, NY, USA
| | - D Stuhr
- Division of Hematology and Oncology, New York Medical College, Valhalla, NY, USA.,Lake Erie College of Osteopathic Medicine, Bradenton, FL, USA
| | - B M Knoll
- Department of Medicine, New York Medical College, Valhalla, NY, USA.,Division of Infectious Diseases, New York Medical College, Valhalla, NY, USA
| | - S H Lim
- From the, Division of Hematology and Oncology, State University of New York Downstate Health Sciences University, Brooklyn, NY, USA.,Division of Hematology and Oncology, New York Medical College, Valhalla, NY, USA
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9
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Carlson TJ, Endres BT, Bassères E, Gonzales-Luna AJ, Garey KW. Ridinilazole for the treatment of Clostridioides difficile infection. Expert Opin Investig Drugs 2019; 28:303-310. [PMID: 30767587 DOI: 10.1080/13543784.2019.1582640] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 02/11/2019] [Indexed: 12/23/2022]
Abstract
INTRODUCTION Ridinilazole is a novel antibiotic being developed for the treatment of Clostridioides difficile infection (CDI). Ridinilazole has completed two phase II trials and phase III trials which are denoted Ri-CoDIFy 1 and 2, are planned (ClinicalTrials.gov identifiers: NCT03595553 and NCT03595566). Areas covered: This article covers the chemistry, mechanism of action, in vitro microbiology versus C. difficile and host microbiota, pre-clinical and clinical efficacy, pharmacokinetics, pharmacodynamics and safety and tolerability of ridinilazole. Expert opinion: Ridinilazole is a novel antibiotic with ideal properties for the treatment of CDI. Given the promising results from the phase II clinical trial, ridinilazole may have the capability to lower the risk for CDI recurrence thus improving sustained clinical response rates - a current unmet medical need. Assuming a positive phase III trial, ridinilazole will enter a market with heightened awareness on the importance of prevention of CDI. This along with further research into the economic consequences and decreased patient quality of life associated with recurrent CDI, should provide clinicians with further evidence for the need for therapy that limits CDI recurrence and improves sustained clinical cure.
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Affiliation(s)
- Travis J Carlson
- a Department of Pharmacy Practice and Translational Research , University of Houston College of Pharmacy , Houston , TX , USA
| | - Bradley T Endres
- a Department of Pharmacy Practice and Translational Research , University of Houston College of Pharmacy , Houston , TX , USA
| | - Eugénie Bassères
- a Department of Pharmacy Practice and Translational Research , University of Houston College of Pharmacy , Houston , TX , USA
| | - Anne J Gonzales-Luna
- a Department of Pharmacy Practice and Translational Research , University of Houston College of Pharmacy , Houston , TX , USA
| | - Kevin W Garey
- a Department of Pharmacy Practice and Translational Research , University of Houston College of Pharmacy , Houston , TX , USA
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10
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Tran MCN, Kullar R, Goldstein EJC. Investigational drug therapies currently in early-stage clinical development for the treatment of clostridioides (clostridium) difficile infection. Expert Opin Investig Drugs 2019; 28:323-335. [DOI: 10.1080/13543784.2019.1581763] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Mai-Chi N. Tran
- Department of Pharmacy, Providence St. John’s Health Center, Santa Monica,
CA, USA
- Department of Pharmacy, Clinica Juan Pablo Medical Group, Los Angeles,
CA, USA
| | | | - Ellie J. C. Goldstein
- R M Alden Research Laboratory, Santa Monica,
CA, USA
- David Geffen School of Medicine, Los Angeles,
CA, USA
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11
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Heidebrecht HJ, Weiss WJ, Pulse M, Lange A, Gisch K, Kliem H, Mann S, Pfaffl MW, Kulozik U, von Eichel-Streiber C. Treatment and Prevention of Recurrent Clostridium difficile Infection with Functionalized Bovine Antibody-Enriched Whey in a Hamster Primary Infection Model. Toxins (Basel) 2019; 11:toxins11020098. [PMID: 30736358 PMCID: PMC6409564 DOI: 10.3390/toxins11020098] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 01/29/2019] [Accepted: 02/01/2019] [Indexed: 12/17/2022] Open
Abstract
Toxin-induced Clostridium difficile infection (CDI) is a major disease characterized by severe diarrhea and high morbidity rates. The aim with this study was to develop an alternative drug for the treatment of CDI. Cows were repeatedly immunized to establish specific immunoglobulin G and A titers against toxins A (TcdA) and B (TcdB) and against C. difficile cells in mature milk or colostrum. The effect of three different concentrations of anti-C. difficile whey protein isolates (anti-CD-WPI) and the standard of care antibiotic vancomycin were investigated in an animal model of CD infected hamsters (6 groups, with 10 hamsters each). WPI obtained from the milk of exactly the same cows pre-immunization and a vehicle group served as negative controls. The survival of hamsters receiving anti-CD-WPI was 50, 80 and 100% compared to 10 and 0% for the control groups, respectively. Vancomycin suppressed the growth of C. difficile and thus protected the hamsters at the time of administration, but 90% of these hamsters nevertheless died shortly after discontinuation of treatment. In contrast, the surviving hamsters of the anti-CD-WPI groups survived the entire study period, although they were treated for only 75 h. The specific antibodies not only inactivated the toxins for initial suppression of CDI, but also provoked the inhibition of C. difficile growth after discontinuation, thus preventing recurrence. Oral administration of anti-CD-WPI is a functional therapy of CDI in infected hamsters for both primary treatment and prevention of recurrence. Thus, anti-CD-WPI could address the urgent unmet medical need for treating and preventing recurrent CDI in humans.
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Affiliation(s)
- Hans-Jürgen Heidebrecht
- Chair of Food and Bioprocess Engineering, Technical University of Munich, 85354 Freising, Germany.
- ZIEL Institute for Food & Health, Technical University of Munich, 85354 Freising, Germany.
| | - William J Weiss
- University of North Texas Health Science Center, Fort Worth, TX 76107-2699, USA.
| | - Mark Pulse
- University of North Texas Health Science Center, Fort Worth, TX 76107-2699, USA.
| | | | | | - Heike Kliem
- Chair of Animal Physiology and Immunology, Technical University of Munich, 85354 Freising, Germany.
| | - Sacha Mann
- Biosys UK Limited, London, SW1H, 9BP, UK.
| | - Michael W Pfaffl
- Chair of Animal Physiology and Immunology, Technical University of Munich, 85354 Freising, Germany.
- School of Life Science, Technical University of Munich, 85354 Freising, Germany.
| | - Ulrich Kulozik
- Chair of Food and Bioprocess Engineering, Technical University of Munich, 85354 Freising, Germany.
- ZIEL Institute for Food & Health, Technical University of Munich, 85354 Freising, Germany.
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12
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Cho JC, Crotty MP, Pardo J. Ridinilazole: a novel antimicrobial for Clostridium difficile infection. Ann Gastroenterol 2018; 32:134-140. [PMID: 30837785 PMCID: PMC6394264 DOI: 10.20524/aog.2018.0336] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 11/07/2018] [Indexed: 12/12/2022] Open
Abstract
Clostridium difficile (C. difficile) infection remains a global healthcare threat worldwide and the limited options available for its treatment are of particular concern. Ridinilazole is one potential future agent, as it demonstrates rapid bactericidal activity against C. difficile. Current studies show that ridinilazole has a lower propensity for collateral damage to the gut microbiome and appears to diminish the production of C. difficile toxins. Results from phase II studies demonstrate that patients receiving ridinilazole had a higher sustained clinical response compared with patients receiving vancomycin (66.7% vs. 42.4%; P=0.0004). Adverse reactions were similar between ridinilazole and vancomycin (40% vs. 56%, respectively), with most being gastrointestinal-related. Nausea (20%) and abdominal pain (12%) were the most commonly reported adverse reactions associated with ridinilazole. Phase II study results are promising and future availability of phase III trial results will help further delineate the role and value of ridinilazole.
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Affiliation(s)
- Jonathan C Cho
- College of Pharmacy, The University of Texas at Tyler, Tyler, TX (Jonathan C. Cho), USA
| | - Matthew P Crotty
- Department of Pharmacy, Methodist Dallas Medical Center, Dallas, TX (Matthew P. Crotty), USA
| | - Joe Pardo
- Department of Pharmacy, North FL/South GA Veterans Health System, Gainesville, FL (Joe Pardo), USA
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Effect of the Synthetic Bile Salt Analog CamSA on the Hamster Model of Clostridium difficile Infection. Antimicrob Agents Chemother 2018; 62:AAC.02251-17. [PMID: 30012758 DOI: 10.1128/aac.02251-17] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 07/01/2018] [Indexed: 12/15/2022] Open
Abstract
Clostridium difficile infection (CDI) is the leading cause of antibiotic-associated diarrhea and has gained worldwide notoriety due to emerging hypervirulent strains and the high incidence of recurrence. We previously reported protection of mice from CDI using the antigerminant bile salt analog CamSA. Here we describe the effects of CamSA in the hamster model of CDI. CamSA treatment of hamsters showed no toxicity and did not affect the richness or diversity of gut microbiota; however, minor changes in community composition were observed. Treatment of C. difficile-challenged hamsters with CamSA doubled the mean time to death, compared to control hamsters. However, CamSA alone was insufficient to prevent CDI in hamsters. CamSA in conjunction with suboptimal concentrations of vancomycin led to complete protection from CDI in 70% of animals. Protected animals remained disease-free at least 30 days postchallenge and showed no signs of colonic tissue damage. In a delayed-treatment model of hamster CDI, CamSA was unable to prevent infection signs and death. These data support a putative model in which CamSA reduces the number of germinating C. difficile spores but does not keep all of the spores from germinating. Vancomycin halts division of any vegetative cells that are able to grow from spores that escape CamSA.
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Vedantam G, Kochanowsky J, Lindsey J, Mallozzi M, Roxas JL, Adamson C, Anwar F, Clark A, Claus-Walker R, Mansoor A, McQuade R, Monasky RC, Ramamurthy S, Roxas B, Viswanathan VK. An Engineered Synthetic Biologic Protects Against Clostridium difficile Infection. Front Microbiol 2018; 9:2080. [PMID: 30233548 PMCID: PMC6134020 DOI: 10.3389/fmicb.2018.02080] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 08/14/2018] [Indexed: 12/18/2022] Open
Abstract
Morbidity and mortality attributed to Clostridium difficile infection (CDI) have increased over the past 20 years. Currently, antibiotics are the only US FDA-approved treatment for primary C. difficile infection, and these are, ironically, associated with disease relapse and the threat of burgeoning drug resistance. We previously showed that non-toxin virulence factors play key roles in CDI, and that colonization factors are critical for disease. Specifically, a C. difficile adhesin, Surface Layer Protein A (SlpA) is a major contributor to host cell attachment. In this work, we engineered Syn-LAB 2.0 and Syn-LAB 2.1, two synthetic biologic agents derived from lactic acid bacteria, to stably and constitutively express a host-cell binding fragment of the C. difficile adhesin SlpA on their cell-surface. Both agents harbor conditional suicide plasmids expressing a codon-optimized chimera of the lactic acid bacterium's cell-wall anchoring surface-protein domain, fused to the conserved, highly adherent, host-cell-binding domain of C. difficile SlpA. Both agents also incorporate engineered biocontrol, obviating the need for any antibiotic selection. Syn-LAB 2.0 and Syn-LAB 2.1 possess positive biophysical and in vivo properties compared with their parental antecedents in that they robustly and constitutively display the SlpA chimera on their cell surface, potentiate human intestinal epithelial barrier function in vitro, are safe, tolerable and palatable to Golden Syrian hamsters and neonatal piglets at high daily doses, and are detectable in animal feces within 24 h of dosing, confirming robust colonization. In combination, the engineered strains also delay (in fixed doses) or prevent (when continuously administered) death of infected hamsters upon challenge with high doses of virulent C. difficile. Finally, fixed-dose Syn-LAB ameliorates diarrhea in a non-lethal model of neonatal piglet enteritis. Taken together, our findings suggest that the two synthetic biologics may be effectively employed as non-antibiotic interventions for CDI.
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Affiliation(s)
- Gayatri Vedantam
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
- Department of Immunobiology, The University of Arizona, Tucson, AZ, United States
- Bio5 Institute for Collaborative Research, The University of Arizona, Tucson, AZ, United States
- Southern Arizona VA Health Care System, Tucson, AZ, United States
| | - Joshua Kochanowsky
- Department of Immunobiology, The University of Arizona, Tucson, AZ, United States
| | - Jason Lindsey
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
| | - Michael Mallozzi
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
| | - Jennifer Lising Roxas
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
| | - Chelsea Adamson
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
| | - Farhan Anwar
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
| | - Andrew Clark
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
| | - Rachel Claus-Walker
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
| | - Asad Mansoor
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
| | - Rebecca McQuade
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
| | - Ross Calvin Monasky
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
| | - Shylaja Ramamurthy
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
| | - Bryan Roxas
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
| | - V. K. Viswanathan
- School of Animal and Comparative Biomedical Sciences, The University of Arizona, Tucson, AZ, United States
- Department of Immunobiology, The University of Arizona, Tucson, AZ, United States
- Bio5 Institute for Collaborative Research, The University of Arizona, Tucson, AZ, United States
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15
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Snydman DR, McDermott LA, Thorpe CM, Chang J, Wick J, Walk ST, Vickers RJ. Antimicrobial susceptibility and ribotypes of Clostridium difficile isolates from a Phase 2 clinical trial of ridinilazole (SMT19969) and vancomycin. J Antimicrob Chemother 2018; 73:2078-2084. [PMID: 29718329 PMCID: PMC6054158 DOI: 10.1093/jac/dky135] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 02/22/2018] [Accepted: 03/20/2018] [Indexed: 12/18/2022] Open
Abstract
Objectives We evaluated the antimicrobial susceptibility and ribotypes of Clostridium difficile isolates from participants in a Phase 2 study of ridinilazole, a novel targeted-spectrum agent for treatment of C. difficile infection. Methods Participants received ridinilazole (200 mg twice daily) or vancomycin (125 mg four times daily) for 10 days (ClinicalTrials.gov: NCT02092935). The MICs of ridinilazole and comparators for C. difficile isolates from stool samples were determined by agar dilution. Toxin gene profiling was performed by multiplex PCR and ribotype identification by capillary electrophoresis. Results Eighty-nine isolates were recovered from 88/100 participants (one participant had two strains at baseline). The median colony count (cfu/g stool) was 1.9 × 104 (range: 2.5 × 102-7.0 × 106). Twelve participants (three received ridinilazole and nine received vancomycin) experienced recurrence, confirmed by immunoassays for free toxin in stool samples. The ribotype of eight out of nine isolates obtained at recurrence matched those of the initial isolates. All isolates, including those obtained at recurrence, were susceptible to ridinilazole within the expected range [median (range) MIC: 0.12 (0.06-0.5) mg/L]. The median (range) vancomycin MIC was 1 (0.5-4.0) mg/L. At baseline, 13.6% and 13.3% of samples in the ridinilazole and vancomycin groups were positive for VRE, increasing to 23.7% and 29.7% by day 40, respectively. Common ribotypes included 014-20 (14 isolates), 027 (13), 106 (7), 002 (7), 078-126 (4), 001 (4), 087 (3) and 198 (3). Toxin gene profiling of nearly all baseline isolates (98.9%) revealed a binary toxin gene (cdtA/cdtB) prevalence of 35%. Conclusions Ridinilazole potently inhibited recovered C. difficile isolates. Recurrence was not associated with altered susceptibility.
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Affiliation(s)
- David R Snydman
- Division of Geographic Medicine and Infectious Diseases and Department of Medicine, Tufts Medical Center, Boston, MA, USA
- Tufts University School of Medicine, Boston, MA, USA
| | - Laura A McDermott
- Division of Geographic Medicine and Infectious Diseases and Department of Medicine, Tufts Medical Center, Boston, MA, USA
| | - Cheleste M Thorpe
- Division of Geographic Medicine and Infectious Diseases and Department of Medicine, Tufts Medical Center, Boston, MA, USA
- Tufts University School of Medicine, Boston, MA, USA
| | - Justin Chang
- Division of Geographic Medicine and Infectious Diseases and Department of Medicine, Tufts Medical Center, Boston, MA, USA
| | - Jenna Wick
- Division of Geographic Medicine and Infectious Diseases and Department of Medicine, Tufts Medical Center, Boston, MA, USA
| | - Seth T Walk
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
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16
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Abstract
Clostridium difficile infection (CDI) represents one of the most serious nosocomial infections that have grown dramatically over the past decade. Vancomycin and metronidazole are currently used as a standard therapy for CDI. Metronidazole is recommended as a first-line therapy for mild-to-moderate infections and vancomycin is mainly used for severe and/or refractory cases. However, studies have demonstrated that there are quite high CDI relapse rates with both of these medications, which represents a challenge for clinicians. Over the last decade, a number of newer and novel therapeutic options have emerged as promising alternatives to these standard CDI therapies. The following review provides the updated summaries of these newer therapeutic agents and their status in the treatment of CDI.
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17
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Petrosillo N, Granata G, Cataldo MA. Novel Antimicrobials for the Treatment of Clostridium difficile Infection. Front Med (Lausanne) 2018; 5:96. [PMID: 29713630 PMCID: PMC5911476 DOI: 10.3389/fmed.2018.00096] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 03/26/2018] [Indexed: 12/17/2022] Open
Abstract
The current picture of Clostridium difficile infection (CDI) is alarming with a mortality rate ranging between 3% and 15% and a CDI recurrence rate ranging from 12% to 40%. Despite the great efforts made over the past 10 years to face the CDI burden, there are still gray areas in our knowledge on CDI management. The traditional anti-CDI antimicrobials are not always adequate in addressing the current needs in CDI management. The aim of our review is to give an update on novel antimicrobials for the treatment of CDI, considering the currently available evidences on their efficacy, safety, molecular mechanism of action, and their probability to be successfully introduced into the clinical practice in the near future. We identified, through a PubMed search, 16 novel antimicrobial molecules under study for CDI treatment: cadazolid, surotomycin, ridinilazole, LFF571, ramoplanin, CRS3123, fusidic acid, nitazoxanide, rifampin, rifaximin, tigecycline, auranofin, NVB302, thuricin CD, lacticin 3147, and acyldepsipeptide antimicrobials. In comparison with the traditional anti-CDI antimicrobial treatment, some of the novel antimicrobials reviewed in this study offer several advantages, i.e., the favorable pharmacokinetic and pharmacodynamic profile, the narrow-spectrum activity against CD that implicates a low impact on the gut microbiota composition, the inhibitory activity on CD sporulation and toxins production. Among these novel antimicrobials, the most active compounds in reducing spore production are cadazolid, ridinilazole, CRS3123, ramoplanin and, potentially, the acyldepsipeptide antimicrobials. These antimicrobials may potentially reduce CD environment spread and persistence, thus reducing CDI healthcare-associated acquisition. However, some of them, i.e., surotomycin, fusidic acid, etc., will not be available due to lack of superiority versus standard of treatment. The most CD narrow-spectrum novel antimicrobials that allow to preserve microbiota integrity are cadazolid, ridinilazole, auranofin, and thuricin CD. In conclusion, the novel antimicrobial molecules under development for CDI have promising key features and advancements in comparison to the traditional anti-CDI antimicrobials. In the near future, some of these new molecules might be effective alternatives to fight CDI.
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Affiliation(s)
- Nicola Petrosillo
- Clinical and Research Department for Infectious Diseases, Unit Systemic and Immunedepression-Associated Infections, National Institute for Infectious Diseases L. Spallanzani, Rome, Italy
| | - Guido Granata
- Clinical and Research Department for Infectious Diseases, Unit Systemic and Immunedepression-Associated Infections, National Institute for Infectious Diseases L. Spallanzani, Rome, Italy
| | - Maria Adriana Cataldo
- Clinical and Research Department for Infectious Diseases, Unit Systemic and Immunedepression-Associated Infections, National Institute for Infectious Diseases L. Spallanzani, Rome, Italy
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18
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Gil F, Calderón IL, Fuentes JA, Paredes-Sabja D. Clostridioides (Clostridium) difficile infection: current and alternative therapeutic strategies. Future Microbiol 2018; 13:469-482. [PMID: 29464969 DOI: 10.2217/fmb-2017-0203] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Clostridioides difficile (C. difficile) has become a pathogen of worldwide importance considering that epidemic strains are disseminated in hospitals of several countries, where community-acquired infections act as a constant source of new C. difficile strains into hospitals. Despite the advances in the treatment of infections, more effective therapies against C. difficile are needed but, at the same time, these therapies should be less harmful to the resident gastrointestinal microbiota. The purpose of this review is to present a description of issues associated to C. difficile infection, a summary of current therapies and those in developmental stage, and a discussion of potential combinations that may lead to an increased efficacy of C. difficile infection treatment.
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Affiliation(s)
- Fernando Gil
- Microbiota-Host Interactions & Clostridia Research Group, Departamento de Ciencias Biológicas, Facultad de Ciencias Biológicas, Universidad Andres Bello, Santiago, 8370035, Chile
| | - Iván L Calderón
- Laboratorio de Genética y Patogénesis Bacteriana, Departamento de Ciencias Biológicas, Facultad de Ciencias Biológicas, Universidad Andres Bello, Santiago, 8370035, Chile
| | - Juan A Fuentes
- Laboratorio de Genética y Patogénesis Bacteriana, Departamento de Ciencias Biológicas, Facultad de Ciencias Biológicas, Universidad Andres Bello, Santiago, 8370035, Chile
| | - Daniel Paredes-Sabja
- Microbiota-Host Interactions & Clostridia Research Group, Departamento de Ciencias Biológicas, Facultad de Ciencias Biológicas, Universidad Andres Bello, Santiago, 8370035, Chile
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Fitzpatrick F, Skally M, Brady M, Burns K, Rooney C, Wilcox MH. European Practice for CDI Treatment. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1050:117-135. [PMID: 29383667 DOI: 10.1007/978-3-319-72799-8_8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Clostridium difficile infection (CDI) remains a significant cause of morbidity and mortality worldwide. Historically, two antibiotics (metronidazole and vancomycin) and a recent third (fidaxomicin) have been used routinely for CDI treatment; convincing data are now available showing that metronidazole is the least efficacious agent. The European Society of Clinical Microbiology and Infectious Diseases CDI treatment guidelines outline the treatment options for a variety of CDI clinical scenarios, including use of the more traditional anti-CDI therapies (e.g., metronidazole, vancomycin), the role of newer anti-CDI agents (e.g., fidaxomicin), indications for surgical intervention and for non-antimicrobial management (e.g., faecal microbiota transplantation, FMT). A 2017 survey of 20 European countries found that while the majority (n = 14) have national CDI guidelines that provide a variety of recommendations for CDI treatment, only five have audited guideline implementation. A variety of restrictions are in place in 13 (65%) countries prior to use of new anti-CDI treatments, including committee/infection specialist approval or economic review/restrictions. Novel anti-CDI agents are being evaluated in Phase III trials; it is not yet clear what will be the roles of these agents. Prophylaxis is an optimum approach to reduce the impact of CDI especially in high-risk populations; monoclonal antibodies, antibiotic blocking approaches and multiple vaccines are currently in advanced clinical trials. The treatment of recurrent CDI is particularly troublesome, and several different live bio therapeutics are being developed, in addition to FMT.
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Affiliation(s)
- Fidelma Fitzpatrick
- Department of Clinical Microbiology, The Royal College of Surgeons in Ireland, Dublin, Ireland.
- Department of Clinical Microbiology, Beaumont Hospital, Dublin, Ireland.
| | - Mairead Skally
- Department of Clinical Microbiology, Beaumont Hospital, Dublin, Ireland
| | - Melissa Brady
- Department of Clinical Microbiology, Beaumont Hospital, Dublin, Ireland
| | - Karen Burns
- Department of Clinical Microbiology, Beaumont Hospital, Dublin, Ireland
- Health Protection Surveillance Centre, Dublin, Ireland
| | - Christopher Rooney
- Microbiology, Leeds Teaching Hospitals and University of Leeds, Leeds, UK
| | - Mark H Wilcox
- Microbiology, Leeds Teaching Hospitals and University of Leeds, Leeds, UK.
- Leeds Teaching Hospitals and University of Leeds, Leeds, UK.
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Vickers RJ, Tillotson GS, Nathan R, Hazan S, Pullman J, Lucasti C, Deck K, Yacyshyn B, Maliakkal B, Pesant Y, Tejura B, Roblin D, Gerding DN, Wilcox MH. Efficacy and safety of ridinilazole compared with vancomycin for the treatment of Clostridium difficile infection: a phase 2, randomised, double-blind, active-controlled, non-inferiority study. THE LANCET. INFECTIOUS DISEASES 2017; 17:735-744. [PMID: 28461207 PMCID: PMC5483507 DOI: 10.1016/s1473-3099(17)30235-9] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 02/21/2017] [Accepted: 03/02/2017] [Indexed: 12/17/2022]
Abstract
BACKGROUND Clostridium difficile infection is the most common health-care-associated infection in the USA. We assessed the safety and efficacy of ridinilazole versus vancomycin for treatment of C difficile infection. METHODS We did a phase 2, randomised, double-blind, active-controlled, non-inferiority study. Participants with signs and symptoms of C difficile infection and a positive diagnostic test result were recruited from 33 centres in the USA and Canada and randomly assigned (1:1) to receive oral ridinilazole (200 mg every 12 h) or oral vancomycin (125 mg every 6 h) for 10 days. The primary endpoint was achievement of a sustained clinical response, defined as clinical cure at the end of treatment and no recurrence within 30 days, which was used to establish non-inferiority (15% margin) of ridinilazole versus vancomycin. The primary efficacy analysis was done on a modified intention-to-treat population comprising all individuals with C difficile infection confirmed by the presence of free toxin in stool who were randomly assigned to receive one or more doses of the study drug. The study is registered with ClinicalTrials.gov, number NCT02092935. FINDINGS Between June 26, 2014, and August 31, 2015, 100 patients were recruited; 50 were randomly assigned to receive ridinilazole and 50 to vancomycin. 16 patients did not complete the study, and 11 discontinued treatment early. The primary efficacy analysis included 69 patients (n=36 in the ridinilazole group; n=33 in the vancomycin group). 24 of 36 (66·7%) patients in the ridinilazole group versus 14 of 33 (42·4%) of those in the vancomycin group had a sustained clinical response (treatment difference 21·1%, 90% CI 3·1-39·1, p=0·0004), establishing the non-inferiority of ridinilazole and also showing statistical superiority at the 10% level. Ridinilazole was well tolerated, with an adverse event profile similar to that of vancomycin: 82% (41 of 50) of participants reported adverse events in the ridinilazole group and 80% (40 of 50) in the vancomycin group. There were no adverse events related to ridinilazole that led to discontinuation. INTERPRETATION Ridinilazole is a targeted-spectrum antimicrobial that shows potential in treatment of initial C difficile infection and in providing sustained benefit through reduction in disease recurrence. Further clinical development is warranted. FUNDING Wellcome Trust and Summit Therapeutics.
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Affiliation(s)
| | | | | | | | | | | | - Kenneth Deck
- Alliance Research Centers, Laguna Hills, CA, USA
| | | | | | - Yves Pesant
- St-Jerome Medical Research, St-Jérôme, QC, Canada
| | | | | | - Dale N Gerding
- Edward Hines Jr Veterans Administration Hospital and Loyola University Chicago, Stritch School of Medicine, Maywood, IL, USA
| | - Mark H Wilcox
- Microbiology, Leeds Teaching Hospitals and University of Leeds, Leeds, UK
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21
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Duvall JR, Bedard L, Naylor-Olsen AM, Manson AL, Bittker JA, Sun W, Fitzgerald ME, He Z, Lee MD, Marie JC, Muncipinto G, Rush D, Xu D, Xu H, Zhang M, Earl AM, Palmer MA, Foley MA, Vacca JP, Scherer CA. Identification of Highly Specific Diversity-Oriented Synthesis-Derived Inhibitors of Clostridium difficile. ACS Infect Dis 2017; 3:349-359. [PMID: 28215073 PMCID: PMC5509442 DOI: 10.1021/acsinfecdis.6b00206] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
In 2013, the Centers for Disease Control highlighted Clostridium difficile as an urgent threat for antibiotic-resistant infections, in part due to the emergence of highly virulent fluoroquinolone-resistant strains. Limited therapeutic options currently exist, many of which result in disease relapse. We sought to identify molecules specifically targeting C. difficile in high-throughput screens of our diversity-oriented synthesis compound collection. We identified two scaffolds with apparently novel mechanisms of action that selectively target C. difficile while having little to no activity against other intestinal anaerobes; preliminary evidence suggests that compounds from one of these scaffolds target the glutamate racemase. In vivo efficacy data suggest that both compound series may provide lead optimization candidates.
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Affiliation(s)
- Jeremy R. Duvall
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, Massachusetts 02142, United States
| | - Leanne Bedard
- WuXi AppTec Early Risk Sharing Group, 1690 Sumneytown Pike, Suite 150, Lansdale, Pennsylvania 19446, United States
| | - Adel M. Naylor-Olsen
- WuXi AppTec Early Risk Sharing Group, 1690 Sumneytown Pike, Suite 150, Lansdale, Pennsylvania 19446, United States
| | - Abigail L. Manson
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, Massachusetts 02142, United States
| | - Joshua A. Bittker
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, Massachusetts 02142, United States
| | - Wenye Sun
- WuXi AppTec, 168 Nanhai Road, TEDA, Tianjin 300457, China
| | - Mark E. Fitzgerald
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, Massachusetts 02142, United States
| | - Zhenmin He
- WuXi AppTec, 168 Nanhai Road, TEDA, Tianjin 300457, China
| | - Maurice D. Lee
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, Massachusetts 02142, United States
| | - Jean-Charles Marie
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, Massachusetts 02142, United States
| | - Giovanni Muncipinto
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, Massachusetts 02142, United States
| | - Diane Rush
- WuXi AppTec Early Risk Sharing Group, 1690 Sumneytown Pike, Suite 150, Lansdale, Pennsylvania 19446, United States
| | - Deming Xu
- WuXi AppTec, 168 Nanhai Road, TEDA, Tianjin 300457, China
| | - Huisheng Xu
- WuXi AppTec, 168 Nanhai Road, TEDA, Tianjin 300457, China
| | | | - Ashlee M. Earl
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, Massachusetts 02142, United States
| | - Michelle A. Palmer
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, Massachusetts 02142, United States
| | - Michael A. Foley
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, Massachusetts 02142, United States
| | - Joseph P. Vacca
- WuXi AppTec Early Risk Sharing Group, 1690 Sumneytown Pike, Suite 150, Lansdale, Pennsylvania 19446, United States
| | - Christina A. Scherer
- Broad Institute of MIT and Harvard, 415 Main Street, Cambridge, Massachusetts 02142, United States
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Fehér C, Soriano A, Mensa J. A Review of Experimental and Off-Label Therapies for Clostridium difficile Infection. Infect Dis Ther 2017; 6:1-35. [PMID: 27910000 PMCID: PMC5336415 DOI: 10.1007/s40121-016-0140-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Indexed: 12/16/2022] Open
Abstract
In spite of increased awareness and the efforts taken to optimize Clostridium difficile infection (CDI) management, with the limited number of currently available antibiotics for C. difficile the halt of this increasing epidemic remains out of reach. There are, however, close to 80 alternative treatment methods with controversial anti-clostridial efficacy or in experimental phase today. Indeed, some of these therapies are expected to become acknowledged members of the recommended anti-CDI arsenal within the next few years. None of these alternative treatment methods can respond in itself to all the major challenges of CDI management, which are primary prophylaxis in the susceptible population, clinical cure of severe cases, prevention of recurrences, and forestallment of asymptomatic C. difficile carriage and in-hospital spread. Yet, the greater the variety of treatment choices on hand, the better combination strategies can be developed to reach these goals in the future. The aim of this article is to provide a comprehensive summary of these experimental and currently off-label therapeutic options.
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Affiliation(s)
- Csaba Fehér
- Department of Infectious Diseases, Hospital Clínic of Barcelona, Barcelona, Spain.
| | - Alex Soriano
- Department of Infectious Diseases, Hospital Clínic of Barcelona, Barcelona, Spain
- August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
- University of Barcelona, Barcelona, Spain
| | - Josep Mensa
- Department of Infectious Diseases, Hospital Clínic of Barcelona, Barcelona, Spain
- August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
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Bassères E, Endres BT, Dotson KM, Alam MJ, Garey KW. Novel antibiotics in development to treat Clostridium difficile infection. Curr Opin Gastroenterol 2017; 33:1-7. [PMID: 28134686 DOI: 10.1097/mog.0000000000000332] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE OF REVIEW Clostridium difficile infections (CDI) remain a challenge to treat clinically due primarily to limited number of antibiotics available and unacceptably high recurrence rates. Because of this, there has been significant demand for creating innovative therapeutics, which has resulted in the development of several novel antibiotics. RECENT FINDINGS This review updates seven different antibiotics that are currently in development to treat CDI including fidaxomicin, surotomycin, ridinilazole, ramoplanin, cadazolid, LFF571, and CRS3123. Available preclinical and clinical data are compared between these antibiotics. SUMMARY Many of these new antibiotics display almost ideal properties for antibiotics directed against CDI. Despite these properties, not all clinical development of these compounds has been successful. These studies have provided key insights into the pathogenesis of CDI and will continue to inform future drug development. Successful phase III clinical trials should result in several new and novel antibiotics to treat CDI.
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Abstract
PURPOSE OF REVIEW Clostridium difficile infection has attained high prominence given its prevalence and impacts on patients and healthcare institutions. Multiple new approaches to the prevention and treatment of C. difficile infection (CDI) are undergoing clinical trials. RECENT FINDINGS Bezlotoxumab is a monoclonal antibody against toxin B that has successfully completed phase III studies, demonstrating a significant reduction in recurrent CDI when given with standard of care antibiotics. Antibiotics under development include cadazolid and ridinilazole, whereas surotomycin has had disappointing phase III results. Multiple live biotherapeutics are being developed, including freeze thawed and encapsulated versions of faecal microbiota transplantation to improve the practicality of treating patients with recurrent CDI. Alternatives to faecal microbiota transplantation, that aim to improve safety, including a microbial suspension, RBX2660, and a complex spore formulation, SER-109, have progressed to phase II studies. A nontoxigenic C. difficile strain has also shown promise to prevent recurrent CDI. In addition, three C. difficile vaccines have progressed to phase II/III clinical trials. SUMMARY The diverse approaches to treating and preventing CDI offer substantial promise that new treatment options will soon emerge, particular ones that reduce the risk of recurrences.
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Affiliation(s)
- Jessica Martin
- aLeeds Teaching Hospitals NHS Trust/University of Leeds, Microbiology, Old Medical School, Leeds General Infirmary bLeeds Teaching Hospitals NHS Trust cUniversity of Leeds, Leeds dPublic Health England, UK
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Vickers RJ, Tillotson G, Goldstein EJC, Citron DM, Garey KW, Wilcox MH. Ridinilazole: a novel therapy for Clostridium difficile infection. Int J Antimicrob Agents 2016; 48:137-43. [PMID: 27283730 DOI: 10.1016/j.ijantimicag.2016.04.026] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 04/22/2016] [Accepted: 04/23/2016] [Indexed: 12/15/2022]
Abstract
Clostridium difficile infection (CDI) is the leading cause of infectious healthcare-associated diarrhoea. Recurrent CDI increases disease morbidity and mortality, posing a high burden to patients and a growing economic burden to the healthcare system. Thus, there exists a significant unmet and increasing medical need for new therapies for CDI. This review aims to provide a concise summary of CDI in general and a specific update on ridinilazole (formerly SMT19969), a novel antibacterial currently under development for the treatment of CDI. Owing to its highly targeted spectrum of activity and ability to spare the normal gut microbiota, ridinilazole provides significant advantages over metronidazole and vancomycin, the mainstay antibiotics for CDI. Ridinilazole is bactericidal against C. difficile and exhibits a prolonged post-antibiotic effect. Furthermore, treatment with ridinilazole results in decreased toxin production. A phase 1 trial demonstrated that oral ridinilazole is well tolerated and specifically targets clostridia whilst sparing other faecal bacteria. Phase 2 and 3 trials will hopefully further our understanding of the clinical utility of ridinilazole for the treatment of CDI.
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Affiliation(s)
- Richard J Vickers
- Summit Therapeutics plc, 85b Park Drive, Milton Park, Abingdon, Oxford OX14 4RY, UK.
| | | | - Ellie J C Goldstein
- R.M. Alden Research Laboratory, Culver City, CA, USA; David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | | | - Kevin W Garey
- University of Houston College of Pharmacy, Houston, TX, USA
| | - Mark H Wilcox
- Microbiology, Leeds Teaching Hospitals and University of Leeds, Old Medical School, Leeds General Infirmary, Leeds, UK
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Slayton ET, Hay AS, Babcock CK, Long TE. New antibiotics in clinical trials for Clostridium difficile. Expert Rev Anti Infect Ther 2016; 14:789-800. [PMID: 27410763 DOI: 10.1080/14787210.2016.1211931] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
INTRODUCTION There are limited number of approved therapies for C. difficile infections (CDIs) and new treatments are needed to decrease recurrence rates. Over the past 5 years, four novel antibiotics have been evaluated in clinical trials that offer distinct advantages over existing therapies for the treatment of CDI. AREAS COVERED This article reviews the preclinical and clinical studies of cadazolid, LFF571, ridinilazole, and surotomycin. The advantages that these antibiotics may have in the treatment of CDI is compared with current therapies metronidazole, vancomycin, and fidaxomicin. Expert commentary: The antibiotics examined have the potential to improve rates of CDI treatment without recurrence. We anticipate that one or more of these medications will be approved within five years.
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Affiliation(s)
- Eric T Slayton
- a Department of Pharmaceutical Science and Research, School of Pharmacy , Marshall University , Huntington , WV , USA
| | - Abigail S Hay
- b Department of Pharmacy Practice, Administration, and Research, School of Pharmacy , Marshall University , Huntington , WV , USA.,c Department of Pharmacy , St. Mary's Medical Center , Huntington , WV , USA
| | - Charles K Babcock
- b Department of Pharmacy Practice, Administration, and Research, School of Pharmacy , Marshall University , Huntington , WV , USA
| | - Timothy E Long
- a Department of Pharmaceutical Science and Research, School of Pharmacy , Marshall University , Huntington , WV , USA.,d Department of Biochemistry and Microbiology, Joan C. Edwards School of Medicine , Marshall University , Huntington , WV , USA
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Antibiotics in the clinical pipeline at the end of 2015. J Antibiot (Tokyo) 2016; 70:3-24. [PMID: 27353164 DOI: 10.1038/ja.2016.72] [Citation(s) in RCA: 250] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 03/24/2016] [Accepted: 05/12/2016] [Indexed: 12/13/2022]
Abstract
There is growing global recognition that the continued emergence of multidrug-resistant bacteria poses a serious threat to human health. Action plans released by the World Health Organization and governments of the UK and USA in particular recognize that discovering new antibiotics, particularly those with new modes of action, is one essential element required to avert future catastrophic pandemics. This review lists the 30 antibiotics and two β-lactamase/β-lactam combinations first launched since 2000, and analyzes in depth seven new antibiotics and two new β-lactam/β-lactamase inhibitor combinations launched since 2013. The development status, mode of action, spectra of activity and genesis (natural product, natural product-derived, synthetic or protein/mammalian peptide) of the 37 compounds and six β-lactamase/β-lactam combinations being evaluated in clinical trials between 2013 and 2015 are discussed. Compounds discontinued from clinical development since 2013 and new antibacterial pharmacophores are also reviewed.
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Bassères E, Endres BT, Khaleduzzaman M, Miraftabi F, Alam MJ, Vickers RJ, Garey KW. Impact on toxin production and cell morphology in Clostridium difficile by ridinilazole (SMT19969), a novel treatment for C. difficile infection. J Antimicrob Chemother 2016; 71:1245-51. [PMID: 26895772 PMCID: PMC4830417 DOI: 10.1093/jac/dkv498] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 12/15/2015] [Accepted: 12/21/2015] [Indexed: 12/17/2022] Open
Abstract
OBJECTIVES Ridinilazole (SMT19969) is a narrow-spectrum, non-absorbable antimicrobial with activity against Clostridium difficile undergoing clinical trials. The purpose of this study was to assess the pharmacological activity of ridinilazole and assess the effects on cell morphology. METHODS Antibiotic killing curves were performed using the epidemic C. difficile ribotype 027 strain, R20291, using supra-MIC (4× and 40×) and sub-MIC (0.125×, 0.25× and 0.5×) concentrations of ridinilazole. Following exposure, C. difficile cells were collected for cfu counts, toxin A and B production, and morphological changes using scanning electron and fluorescence microscopy. Human intestinal cells (Caco-2) were co-incubated with ridinilazole-treated C. difficile growth medium to determine the effects on host inflammatory response (IL-8). RESULTS Treatment at supra-MIC concentrations (4× and 40× MIC) of ridinilazole resulted in a significant reduction in vegetative cells over 72 h (4 log difference, P < 0.01) compared with controls without inducing spore formation. These results correlated with a 75% decrease in toxin A production (P < 0.05) and a 96% decrease in toxin B production (P < 0.05). At sub-MIC levels (0.5× MIC), toxin A production was reduced by 91% (P < 0.01) and toxin B production was reduced by 100% (P < 0.001), which resulted in a 74% reduction in IL-8 release compared with controls (P < 0.05). Sub-MIC (0.5×)-treated cells formed filamentous structures ∼10-fold longer than control cells. Following fluorescence labelling, the cell septum was not forming in sub-MIC-treated cells, yet the DNA was dividing. CONCLUSIONS Ridinilazole had robust killing effects on C. difficile that significantly reduced toxin production and attenuated the inflammatory response. Ridinilazole also elicited significant cell division effects suggesting a potential mechanism of action.
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Affiliation(s)
- Eugénie Bassères
- University of Houston College of Pharmacy, 1441 Moursund Street, Houston, TX 77030, USA
| | - Bradley T Endres
- University of Houston College of Pharmacy, 1441 Moursund Street, Houston, TX 77030, USA
| | | | - Faranak Miraftabi
- University of Houston College of Pharmacy, 1441 Moursund Street, Houston, TX 77030, USA
| | - M Jahangir Alam
- University of Houston College of Pharmacy, 1441 Moursund Street, Houston, TX 77030, USA
| | - Richard J Vickers
- Summit Therapeutics, 85b Park Drive, Milton Park, Abingdon, Oxfordshire OX14 4RY, UK
| | - Kevin W Garey
- University of Houston College of Pharmacy, 1441 Moursund Street, Houston, TX 77030, USA
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Affiliation(s)
- Matthew C T Fyfe
- Topivert Limited, Imperial College Incubator, London, United Kingdom
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Mann J, Taylor PW, Dorgan CR, Johnson PD, Wilson FX, Vickers R, Dale AG, Neidle S. The discovery of a novel antibiotic for the treatment of Clostridium difficile infections: a story of an effective academic-industrial partnership. MEDCHEMCOMM 2015; 6:1420-1426. [PMID: 26949507 PMCID: PMC4756575 DOI: 10.1039/c5md00238a] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 06/30/2015] [Indexed: 12/13/2022]
Abstract
The story of the discovery of the bis-benzimidazole derivative SMT19969, which is currently in clinical trials against the pathogen Clostridium difficile.
Academic drug discovery is playing an increasingly important role in the identification of new therapies for a wide range of diseases. There is no one model that guarantees success. We describe here a drug discovery story where chance, the ability to capitalise on chance, and the assembling of a range of expertise, have all played important roles in the discovery and subsequent development of an antibiotic chemotype based on the bis-benzimidazole scaffold, with potency against a number of current therapeutically challenging diseases. One compound in this class, SMT19969, has recently entered Phase 2 human clinical trials for the treatment of Clostridium difficile infections.
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Affiliation(s)
- John Mann
- UCL School of Pharmacy , University College London , London WC1N 1AX , UK .
| | - Peter W Taylor
- UCL School of Pharmacy , University College London , London WC1N 1AX , UK .
| | | | | | | | | | - Aaron G Dale
- UCL School of Pharmacy , University College London , London WC1N 1AX , UK .
| | - Stephen Neidle
- UCL School of Pharmacy , University College London , London WC1N 1AX , UK .
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