Author Archives: cdifffoundation

Study Investigators Find Combination of Vancomycin and FMT Superior In Treating Recurrent C.difficile Infection (rCDI)

The combination of vancomycin and fecal microbiota transplantation was found to be superior to fidaxomicin or vancomycin in the treatment of patients with recurrent Clostridium difficile infection (rCDI), according to a study published in Gastroenterology.

This randomized, single-center trial was designed to compare the efficacy of fecal microbiota transplantation with that of fidaxomicin and vancomycin.

Sixty-four adults with recurrent CDI seen at a gastroenterology clinic in Denmark between April 5, 2016 and June 10, 2018 were randomly assigned to a group receiving fecal microbiota transplantation applied by colonoscopy or nasojejunal tube after 4 to 10 days of 125 mg vancomycin 4 times daily (n=24), or 10 days of 200 mg fidaxomicin 2 times daily (n=24), or 10 days of 125 mg vancomycin 4 times daily (n=16).

Patients experiencing a CDI recurrence after this course of treatment, and those who could not be randomly assigned were provided rescue fecal microbiota transplantation. The primary study outcome was combined clinical resolution and negative polymerase chain reaction test for C difficile toxin at 8 weeks post-treatment, and secondary end points included week 8 clinical resolution.

The combination of negative C difficile test results and clinical resolution was observed in 71% of the 24 participants who received fecal microbiota transplantation (95% CI, 49-87%; n=17), 33% of the 24 participants who received fidaxomicin (95% CI, 16-55%; n=8), and 19% of the 16 participants (95% CI, 5-46%; n=3) who received vancomycin (fecal microbiota transplantation vs fidaxomicinP=.009; fecal microbiota transplantation vs vancomycin, P=.001; fidaxomicin vs vancomycin, P=.31). Clinical resolution was observed in 92% of participants who received fecal microbiota transplantation (n=22; P=.0002), 42% of participants who were treated with fidaxomicin (n=10; <.0001), and 19% of participants who were treated with vancomycin (n=3; P=.13). No significant differences in results were seen between patients receiving initial fecal microbiota transplantation therapy and those who received rescue treatment with such a transplant.

Of note, adverse events (transient abdominal pain, constipation, bloating and diarrhea) were observed in 10 of the participants who received a fecal microbiota transplant, 1 of which was classified as severe.

Researchers noted limitation of a lack of patients with C difficile ribotype 027, such that results may not be generalizable to settings with a high ribotype 027 frequency. Study interventions were also unblinded, introducing the possibility of observer bias, although the C difficile toxin test was applied to all patients at all time points in an effort to obtain objective outcome measures.

Study investigators concluded, “[fecal microbiota transplantation] was superior to both fidaxomicin and vancomycin monotherapies for [recurrent] CDI, with regard to both combined clinical and microbiological resolution and clinical resolution alone.”

Reference

https://www.infectiousdiseaseadvisor.com/respiratory/new-powder-formulation-tuberculosis-vaccine-candidate-is-in-human-trial/article/829508/

Hvas CL, Jørgensen SMD, Jørgensen SP, et al. Fecal microbiota transplantation is superior to fidaxomicin for treatment of recurrent Clostridium difficile infection [published online January 2, 2019]. Gastroenterology. doi: 10.1053/j.gastro.2018.12.019

Summit Therapeutics Doses First Patient in Global Phase 3 Clinical Trials Oral Antibiotic ridinilazole for C.difficile Infection Treatment

Summit Doses First Patient in Phase 3 Clinical Trials of Precision Antibiotic Ridinilazole for C. Difficile Infection

  • Trials Aim to Show Superiority of Ridinilazole Over Standard of Care Treatment Vancomycin
  • Health Economic Outcomes Included to Support Commercialisation

FROM PRESS RELEASE:

Oxford, UK, and Cambridge, MA, US, 13 February 2019 – Summit Therapeutics plc (NASDAQ: SMMT, AIM: SUMM), a leader in new mechanism antibiotic innovation, today announces it has dosed the first patient in the global Phase 3 clinical trials of its precision oral antibiotic, ridinilazole, for C. difficile infection (‘CDI’). The trials aim to show superiority of ridinilazole over the standard of care, vancomycin, in a measure that combines CDI cure and recurrence called sustained clinical response (‘SCR’). Ridinilazole achieved statistical superiority over vancomycin in SCR in a Phase 2 clinical trial.

“Starting our Phase 3 programme is an important milestone for Summit,” commented Mr Glyn Edwards, Chief Executive Officer of Summit. With positive results, we believe ridinilazole could be positioned as the drug of choice in the front-line treatment of CDI, which potentially provides patients with sustained cures and hospitals with compelling cost savings.”

“Ridinilazole is the trail-blazer in our growing pipeline of innovative product candidates targeting serious infectious diseases,” added Dr David Roblin, President of R&D of Summit. “Our Phase 3 programme exemplifies our broader strategy of demonstrating significant advantages over current standards of care by gathering a carefully considered package of clinical and economic data to address the needs of physicians, regulators, healthcare providers, payors and, above all, patients.”

The Phase 3 clinical programme comprises two global, randomised, double-blind, active-controlled clinical trials called Ri-CoDIFy 1 and Ri-CoDIFy 2. The trials will be run concurrently with each expected to enrol approximately 680 patients at sites in North America, Latin America, Europe, Australia and Asia. Upon confirmation of a positive CDI toxin test, patients will be randomised to receive either ridinilazole (200mg twice a day) or vancomycin (125mg four times a day) for ten days. The primary endpoint of both clinical trials will test for superiority in SCR, defined as cure at the end of treatment and no recurrence of CDI within 30 days post-treatment. Secondary endpoints include cure at the end of treatment and SCR at 60 days and 90 days post-treatment. Additional endpoints will evaluate the impact of ridinilazole and vancomycin on the gut microbiome, which is known to protect against CDI. The Phase 3 clinical trials also include health economic outcome measures, such as readmission rates and length of hospital stay, to help support the commercialisation of ridinilazole, if approved.

Top-line data from the Phase 3 programme are expected to be reported in the second half of 2021.

The clinical and regulatory development of ridinilazole is being funded in part with Federal funds from the US Department of Health and Human Services, Office of the Assistant Secretary for Preparedness and Response, Biomedical Advanced Research and Development Authority (‘BARDA’), under Contract No. HHS0100201700014C. Summit is eligible to receive up to $62 million in funding from BARDA to support the clinical and regulatory development of ridinilazole.

About Ridinilazole
Ridinilazole is an oral small molecule new mechanism antibiotic that is designed to selectively kill C. difficile, thereby preserving patients’ protective gut microbiome and leading to sustained CDI cures. In a Phase 2 proof of concept trial in CDI patients, ridinilazole showed statistical superiority in sustained clinical response (‘SCR’) rates compared to the standard of care, vancomycin. In that trial, SCR was defined as clinical cure at end of treatment and no recurrence of CDI within 30 days of the end of therapy. Ridinilazole was also shown to be highly preserving of the gut microbiome in the Phase 2 proof of concept trial, which was believed to be the reason for the improved clinical outcome for the ridinilazole-treated patients. In addition, ridinilazole preserved the gut microbiome to a greater extent than the marketed narrow-spectrum antibiotic fidaxomicin in an exploratory Phase 2 clinical trial. Ridinilazole has received Qualified Infectious Disease Product (‘QIDP’) designation and has been granted Fast Track designation by the US Food and Drug Administration. The QIDP incentives are provided through the US GAIN Act and include a potential extension of marketing exclusivity for an additional five years upon FDA approval.

About Summit Therapeutics
Summit Therapeutics is a leader in antibiotic innovation. Our new mechanism antibiotics are designed to become the new standards of care for the benefit of patients and create value for payors and healthcare providers. We are currently developing new mechanism antibiotics for infections caused by C. difficile, N. gonorrhoeae and ESKAPE pathogens and are using our proprietary Discuva Platform to expand our pipeline.

For more information, visit www.summitplc.com

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Ribotypes and Prevalence of Clostridium difficile (C. diff) Hypervirulent Strain: NAP1/B1/027

The Hypervirulent Strain of Clostridium Difficile: NAP1/B1/027

– A Brief Overview



Abstract

Clostridium difficile is a gram-positive bacterium notorious for causing epidemic diarrhea globally with a significant health burden. The pathogen is clinically challenging with increasing antibiotic resistance and recurrence rate. We provide here an in-depth review of one particular strain/ribotype 027, commonly known as NAP1/B1/027 or North American pulsed-field gel electrophoresis type 1, restriction endonuclease analysis type B1, polymerase chain reaction ribotype 027, which has shown a much higher recurrence rate than other strains.

Introduction & Background

Clostridium difficile (C. diff) is a gram-positive, anaerobic, motile, spore-forming, rod-shaped bacteria [1-2]. It has been isolated from almost all mammals, including pigs, cows, horses, elephants, and Kodiak bears, as well as in poultry and ostriches. It has also been found in the soil and feces of humans and animals. It is transmitted from person to person by the fecal-oral route. The C. diff isolates found in animals are similar to the ones found in humans, but according to Hensgens et al., this similarity does not mean that interspecies transmission occurs. However, immunocompromised people are still at risk for interspecies transmission [1]. Its pathogenicity is dependent on the two toxins that it produces: enterotoxin A (Toxin A or TcdA) and cytotoxin B (Toxin B or TcdB). Enterotoxin damages the actin in target cells which leads to neutrophil infiltration, inflammation, and necrosis of epithelial cells. Cytotoxin B has been shown to damage tight junctions of epithelial cells, which increases vascular permeability and causes hemorrhage [2-3]. These toxins form the basis of stool analysis when diagnosing people with the suspected infection. Despite all the virulence characters described, C. diff is a poor competitor against other gut flora in the human colon. In a healthy colon, this pathogen is not in sufficient quantity to produce a clinically significant disease. Risk factors that disrupt this balance include antibiotics exposure, health care environment, acid suppressants, and elemental diet. The bacterium can cause severe watery diarrhea that can progress to pseudomembranous colitis [3-8]. It has been named as one of the three microorganisms with an ‘urgent’ threat level by the Centers for Disease Control and Prevention (CDC) based on its public health impact in the United States (US) with an estimated $1.5 billion US in annual health care expenditures [8]. Patients who have more than three episodes of unexplained and new onset unformed stools in 24 hours should be referred for testing for a Clostridium difficile infection (CDI). Also, patients with risk factors described previously should undergo testing for this pathogen [9]. The ribotype 027 strain of C. diff is particularly noteworthy as contradicting evidence in the literature is present regarding the disease severity it causes. We provide here a brief overview of the epidemiology, pathophysiology, and treatment of this particular strain.

Review

Ribotypes and prevalence of Clostridium difficile (C. diff)

Clostridium difficile can be characterized according to its ribotyping which is performed using the polymerase chain reaction. Several different ribotypes have been associated with CDI. The ribotypes 001, 002, 014, 046, 078, 126, and 140 have been found to be prevalent in the Middle East [10-12]. In Asia, ribotypes 001, 002, 014, 017, and 018 are more prevalent [13-15]. The predominant strains in Europe and North America include ribotypes 001, 014, 020, 027, and 078 [6]. The ribotype 027 (also referred to as NAP1/B1/027) has emerged in the last decade. Studies have underlined antimicrobial resistance as one of the causes of its epidemic outbreaks. Capillary electrophoresis (CE) ribotyping is used as the standard for characterization of C. diff isolates. This method relies on the intergeneric region variability between 16S and 23S ribosomal deoxyribonucleic acid (DNA) [16]. Ribotype 027 was found to have reduced susceptibility to metronidazole, rifampicin, moxifloxacin, clindamycin, imipenem, and chloramphenicol [17-18]. It is clinically and financially concerning as it leads to severe disease presentation, as well as antimicrobial resistance with high morbidity and mortality rates as compared to other strains [19]. Strains, such as ribotype 027 (especially its spores), spread more easily within the hospital because they can resist the hospital environment, cleaning, and disinfectants [1]. An observational study conducted on patients admitted with diarrhea in a Veteran Affairs Medical Center showed that around 22% of the patients were positive for the NAP1/B1/027 strain out of all the people who tested positive for CDI. Further, a reduction in the rate of diarrhea caused by the NAP1/B1/027 strain was observed with a prevalence of 16.9% in 2016, down from 26.2% in 2013. An increase in the level of awareness and education was thought to be the reason for this decline [20]. The prevalence of this strain in North America is reportedly around 22% – 36%. Ribotype 027 was identified as the most prevalent strain causing CDI with recent outbreaks in North America [20-22]. The prevalence of this strain was shown to be 48% in hospitals in Poland with an outbreak of CDI during September 2011 to August 2013 [21].

NAP1/B1/027 strain

Toxigenicity and Pathogenesis

The North American pulsed-field gel electrophoresis type 1, restriction endonuclease analysis type B1, polymerase chain reaction ribotype 027 (NAP1/B1/027) strain has been shown to contain a gene locus, CdtLoc, that encodes for CD196 ADP-ribosyltransferase (CDT) or binary toxin. The bacterium also produces Toxin A and Toxin B, similar to non-027 ribotypes, through the PaLoc gene locus [23-24]. CDT was first isolated by Popoff et al. [25]. The toxin comprises two separate toxin components: CDTa and CDTb. CDTa, which is an ADP-ribosyltransferase enzyme, modifies actin which results in depolymerization and destruction of the actin cytoskeleton in the gut. CDTb binds to gut cells and increases uptake of CDTa. The destruction caused by CDT favors adherence of bacteria and increased uptake of Toxin A and Toxin B [26].

In addition to the toxins, this strain (along with few others) carries a base pair frameshift deletion at nucleotide 117 of the TcdC gene, which is a negative regulator of Toxins A and B. A mutation in this gene thus causes hyperexpression of toxins by this particular strain. Warny et al. showed that NAP1/B1/027 produces Toxin A approximately 16 times and Toxin B approximately 23 times more than the control strains [27]. One study also proposed that increased sporulation by this strain may also be associated with the increased spread of CDI [28]. The virulent factors associated with NAP1/B1/027 strain have been summarized in Table 1.

Virulent factor Mechanism
1. Toxin A (Enterotoxin A or TcdA) Damages the actin in target cells which leads to neutrophil infiltration, inflammation, and necrosis of epithelial cells [24].
2. Toxin B (Cytotoxin B or TcdB) Damages tight junctions of epithelial cells, which increases vascular permeability and causes hemorrhage [24].
3. CDTa toxin Modification of actin with ADP-ribosylation that results in actin depolymerization and destruction of the cytoskeleton that assists in adherence of bacteria to gut epithelial cells [25-26].
4. CDTb toxin Facilitates uptake of CDTa toxin into the gut epithelial lining [25-26].
5. Hypersporulation Increases reproduction and spread of bacteria [28].
6. TcdC gene mutation (18-bp deletion) Increases the production of Toxin A and Toxin B by down-regulation of feedback inhibitor involved in suppressing toxin production [27].

Previous studies have shown contradicting evidence regarding the severity of disease caused by this particular strain. A recent retrospective analysis by Bauer et al. concluded that NAP1/B1/027 was associated with a decreased odds of severe disease (odds ratio (OR): 0.35, 95% confidence interval (CI) 0.13 – 0.93) and did not increase in-hospital mortality (OR: 1.02, 95% CI 0.53 – 1.96) or recurrence rate (OR: 1.16, 95% CI 0.36 – 3.77) [23]. Several other studies conducted (including cross-sectional, case-control, and cohort studies) did not show any worse outcomes compared to other strains [29-31]. Sirad et al. demonstrated that although NAP1/B1/027 strain may produce more toxins compared to other strains, they produced fewer spores and were not always associated with severe disease [32]. On the contrary, Rao et al. conducted a cohort study and concluded that ribotype 027 was associated with severe CDI (OR: 1.73, 95% CI 1.03 – 2.89; p = 0.037) and increased mortality (OR: 2.02, 95% CI 1.19 – 3.43; p = 0.009) compared to other ribotypes [24]. Another study showed similar results with the North American pulsed-field gel electrophoresis type 1 (NAP1) strain. Multivariate regression analysis exhibited an increase in the severity of CDI with the NAP1 strain (OR: 1.66, 95% CI: 1.90 – 2.54) and increased mortality (OR: 2.12, 95% CI: 1.22 – 3.68) [33]. One study from Quebec labeled this strain to be responsible for severe diseases twice as frequently as compared to other strains [34].

The basis for these contradictory findings can be explained by several reasons, including study design, study population, sample size, the method of detection for C. diff, study setting, and unmeasured confounders. Given these contradictory results, healthcare providers should focus on treating this infection based on their clinical judgment and markers of severe infection, including the number of diarrheal episodes, signs of dehydration, creatinine level, albumin level, white blood cell count, associated co-morbidities, immunocompromised state, etc.

Prevention

Preventive strategies employed for NAP1/B1/027 strain are similar to strategies taken for other strains. These include barrier methods (gloves and gown while examining patient), use of disposable equipment, handwashing with soap and water, disinfecting the environment, and antimicrobial stewardship [35]. Further vaccines are being developed targeting the toxins, including TcdA and TcdB, for simultaneous prevention and treatment of CDI. Actoxumab and bezlotoxumab, which are monoclonal antibodies against TcdA and TcdB, are being investigated for this purpose. A combined Phase III trial (MODIFY I (NCT01241552) and MODIFY II (NCT01513239)) showed benefit from bezlotoxumab, but the combination of actoxumab and bezlotoxumab did not yield any further benefit [36]. Bezlotoxumab has received Food and Drug Administration (FDA) approval in October 2016 and is to be used in patients more than 18 years of age, who are at high risk of recurrence from CDI, and are receiving antibiotics [37]. A novel tetravalent vaccine against TcdA, TcdB, CDTa, and CDTb has been proposed by Secore et al. using a hamster model which has shown promising results [38].

A novel drug, SYN-004 (ribaxamase), is under investigation that has shown promising results for preventing CDI. This drug, which is a β-lactamase, is excreted into the gut and degrades the excess antibiotic that prevents disruption of normal gut flora, ultimately preventing CDI [39]. The Phase IIa clinical trial of this drug showed that ribaxamase at a dose of 150 mg every six hours results in an undetectable concentration of ceftriaxone in the intestine which can potentially decrease the likelihood of a C. diff infection, given the less probability of disruption of the gut bacteria.

Resistance to Antibiotics and Treatment

Cases of NAP1/B1/027 reported in Panama were found to be highly resistant to clindamycin, moxifloxacin, levofloxacin, ciprofloxacin, and rifampin but were susceptible to metronidazole and vancomycin [40]. Susceptibility of ribotype 027 and non-027 ribotypes to different antibiotics was tested in a study in Canada. Ribotype 027 showed a resistance of 92.2% to moxifloxacin compared to 11.2% for other strains. Similarly, 78.2% of ribotype 027 strains were resistant to ceftriaxone compared to 15.7% of other strains. Ribotype 027 demonstrated a greater than four-fold higher minimum inhibitory concentration (MIC) to metronidazole (4 vs. 1 μg/ml) and two-fold higher MIC for fidaxomicin (1 vs. 2 μg/ml). For clindamycin and vancomycin, the resistance was similar in both groups [41].

Resistance to erythromycin is linked to mutations in the ribosomal methylase genes, whereas resistance to fluoroquinolones is due to a mutation in DNA gyrase. Resistance to rifamycin and fidaxomicin is attributed to ribonucleic acid (RNA) polymerase methylation. The presence of phenicol and lincosamide genes has been shown to cause resistance to linezolid. A study conducted in hospitals of Mexico showed some isolates of ribotype 027 to have reduced susceptibility to fidaxomicin despite the unavailability of this drug in Mexico and the patients being unexposed to it [42]. Antibiotics form the basis of treatment for the NAP1/B1/027 strain. Currently, no specific Infectious Diseases Society of America (IDSA) guidelines are available to guide treatment for this particular strain, and hence, the treatment is similar to a non-NAP1/B1/027 strain [9]. Based on the current guidelines for treating CDI overall, we propose the following table for treating infection caused by the NAP1/B1/027 strain (Table 2).

First line treatment Alternative treatment
Initial non-severe infection Oral vancomycin, 125 mg four times daily for 10 days Fidaxomicin, 200 mg twice daily for 10 days; If neither is available, then use metronidazole, 500 mg three times daily for 10 days
First non-severe recurrence Repeat oral vancomycin, 125 mg four times daily for 10 days Fidaxomicin, 200 mg twice daily for 10 days
Second non-severe recurrence Oral vancomycin taper as follow: 125 mg four times daily for seven to 14 days, 125 mg twice daily for seven days, 125 mg twice once daily for seven days, 125 mg once every other day for seven days, 125 mg once every three days for 14 days Fidaxomicin, 200 mg orally twice daily for 10 days, or a fecal microbiota transplant
Subsequent non-severe recurrence Fecal microbiota transplant Tapering oral vancomycin with probiotics, IVIG, fidaxomicin
Severe disease Oral vancomycin, 125 mg four times daily, increase to 500 mg four times daily if no improvement noted in 24-48 hours or associated complications, including renal failure, ileus, etc. Fidaxomicin if the patient cannot tolerate oral vancomycin for any reason
Ileus Add IV metronidazole, 500 mg every eight hours, to oral vancomycin or fidaxomicin therapy; consider general surgery consult as needed Intracolonic vancomycin, IVIG

This strain has not shown any resistance to fidaxomicin, but there has been some contradicting evidence to this. A case report was published in 2017 in which the NAP1 C. diff infection, resistant to treatment with fidaxomicin and fecal transplants, was effectively treated with intravenous immunoglobulin (IVIG) [43]. Given the emerging threat of antibiotic resistance, increasing awareness, controlling infections, and antimicrobial stewardship can be effective measures to reduce this threat [17].

Currently, several novel antibiotics are under investigation which have gone through various randomized controlled trials for CDI treatment. Ridinilazole and cadazolid have completed Phase II trials, while surotomycin has completed two Phase III trials which have shown promising results [44-47].

Conclusions

The data regarding the NAP1/B1/027 strain is inconclusive with ongoing debates whether this particular strain is associated with severe disease. Further research, including meta-analyses, are needed to solve this enigma. Clinicians should guide treatment based on their judgment and objective evidence of disease severity.


References

  1. Hensgens MP, Keessen EC, Squire MM, et al.: Clostridium difficile infection in the community: a zoonotic disease?. Clin Microbiol Infect. 2012, 18:635-45. 10.1111/j.1469-0691.2012.03853.x
  2. Aziz M, Fatima R, Douglass L, Abughanimeh O, Raza S: Current updates in management of Clostridium difficile infection in cancer patients. Curr Med Res Opin. 2018, Epub ahead of print:1-6. 10.1080/03007995.2018.1487389
  3. Sachsenheimer FE, Yang I, Zimmermann O, et al.: Genomic and phenotypic diversity of Clostridium difficile during long-term sequential recurrences of infection. Int J Med Microbiol. 2018, 308:364-77. 10.1016/j.ijmm.2018.02.002
  4. Luciano JA, Zuckerbraun BS: Clostridium difficile infection: prevention, treatment, and surgical management. Surg Clin North Am. 2014, 94:1335-49. 10.1016/j.suc.2014.08.006
  5. Clabots CR, Johnson S, Olson MM, Peterson LR, Gerding DN: Acquisition of Clostridium difficile by hospitalized patients: evidence for colonized new admissions as a source of infection. J Infect Dis. 1992, 166:561-67. 10.1093/infdis/166.3.561
  6. Howell M, Novack V, Grgurich P, Soulliard D, Novack L, Pencina M, Talmor D: Iatrogenic gastric acid suppression and the risk of nosocomial Clostridium difficile infection. Arch Intern Med. 2010, 170:784-90. 10.1001/archinternmed.2010.89
  7. O’Keefe S: Tube feeding, the microbiota, and Clostridium difficile infection. World J Gastroenterol. 2010, 16:139-42. 10.3748/wjg.v16.i2.139
  8. Hampton T: Report reveals scope of US antibiotic resistance threat. JAMA. 2013, 310:1661-63. 10.1001/jama.2013.280695
  9. McDonald LC, Gerding DN, Johnson S, et al.: Clinical practice guidelines for Clostridium difficile infection in adults and children: 2017 update by the Infectious Diseases Society of America (IDSA) and Society for Healthcare Epidemiology of America (SHEA). Clin Infect Dis. 2018, 66:e1-e48. 10.1093/cid/cix1085
  10. Jamal W, Rotimi VO, Brazier J, Duerden BI: Analysis of prevalence, risk factors and molecular epidemiology of Clostridium difficile infection in Kuwait over a 3-year period. Anaerobe. 2010, 16:560-65. 10.1016/j.anaerobe.2010.09.003
  11. Jalali M, Khorvash F, Warriner K, Weese J: Clostridium difficile infection in an Iranian hospital. BMC Res Notes. 2012, 5:159. 10.1186/1756-0500-5-159
  12. Al-Thani AA, Hamdi WS, Al-Ansari NA, Doiphode SH, Wilson GJ: Polymerase chain reaction ribotyping of Clostridium difficile isolates in Qatar: a hospital-based study. BMC Infect Dis. 2014, 14:502. 10.1186/1471-2334-14-502
  13. Sawabe E, Kato H, Osawa K, Chida T, Tojo N, Arakawa Y, Okamura N: Molecular analysis of Clostridium difficile at a university teaching hospital in Japan: a shift in the predominant type over a five-year period. Eur J Clin Microbiol Infect Dis. 2007, 26:695-703. 10.1007/s10096-007-0355-8
  14. Cheng V, Yam W, Lam O, et al.: Clostridium difficile isolates with increased sporulation: emergence of PCR ribotype 002 in Hong Kong. Eur J Clin Microbiol Infect Dis. 2011, 30:1371-81. 10.1007/s10096-011-1231-0
  15. Kim H, Lee Y, Moon H, Lim C, Lee K, Chong Y: Emergence of Clostridium difficile ribotype 027 in Korea. Korean J Lab Med. 2011, 31:191-96. 10.3343/kjlm.2011.31.3.191
  16. Krutova M, Nyc O, Matejkova J, Kuijper E, Jalava J, Mentula S: The recognition and characterisation of Finnish Clostridium difficile isolates resembling PCR-ribotype 027. J Microbiol Immunol Infect. 2018, 51:344-51. 10.1016/j.jmii.2017.02.002
  17. Freeman J, Vernon J, Pilling S, et al.: The ClosER study: results from a three-year pan-European longitudinal surveillance of antibiotic resistance among prevalent Clostridium difficile ribotypes, 2011-2014. Clin Microbiol Infect. 2018, 24:724-31. 10.1016/j.cmi.2017.10.008
  18. Goldstein EJ, Citron DM, Sears P, Babakhani F, Sambol SP, Gerding DN: Comparative susceptibilities of fidaxomicin (OPT-80) of isolates collected at baseline, recurrence, and failure from patients in two fidaxomicin phase III trials of fidaxomicin against Clostridium difficile infection. Antimicrob Agents Chemother. 2011, 55:5194-99. 10.1128/AAC.00625-11
  19. Camacho-Ortiz A, López-Barrera D, Hernández-García R, et al.: Correction: First report of Clostridium difficile NAP1/027 in a Mexican hospital. PLoS One. 2015, 10:e0129079. 10.1371/journal.pone.0129079
  20. Giancola S, Williams R, Gentry C: Prevalence of the Clostridium difficile BI/NAP1/027 strain across the United States Veterans Health Administration. Clin Microbiol Infect. 2018, 24:877-81. 10.1016/j.cmi.2017.11.011
  21. Pituch H, Obuch-Woszczatyński P, Lachowicz D, et al.: Prevalence of Clostridium difficile infection in hospitalized patients with diarrhoea: results of a Polish multicenter, prospective, biannual point-prevalence study. Adv Med Sci. 2018, 63:290-95. 10.1016/j.advms.2018.03.003
  22. DePestel DD, Aronoff DM: Epidemiology of Clostridium difficile infection. J Pharm Pract. 2013, 26:464-75. 10.1177/0897190013499521
  23. Bauer KA, Johnston JEW, Wenzler E, et al.: Impact of the NAP-1 strain on disease severity, mortality, and recurrence of healthcare-associated Clostridium difficile infection. Anaerobe. 2017, 48:1-6. 10.1016/j.anaerobe.2017.06.009
  24. Rao K, Micic D, Natarajan M, et al.: Clostridium difficile ribotype 027: relationship to age, detectability of toxins A or B in stool with rapid testing, severe infection, and mortality. Clin Infect Dis. 2015, 61:233-41. 10.1093/cid/civ254
  25. Popoff MR, Rubin EJ, Gill DM, Boquet P: Actin-specific ADP-ribosyltransferase produced by a Clostridium difficile strain. Infect Immun. 1988, 56:2299-306.
  26. Gerding DN, Johnson S, Rupnik M, Aktories K: Clostridium difficile binary toxin CDT: mechanism, epidemiology, and potential clinical importance. Gut Microbes. 2014, 5:15-27. 10.4161/gmic.26854
  27. Warny M, Pepin J, Fang A, et al.: Toxin production by an emerging strain of Clostridium difficile associated with outbreaks of severe disease in North America and Europe. Lancet. 2005, 366:P1079-84. 10.1016/s0140-6736(05)67420-x
  28. Akerlund T, Persson I, Unemo M, Norén T, Svenungsson B, Wullt M, Burman LG: Increased sporulation rate of epidemic Clostridium difficile Type 027/NAP1. J Clin Microbiol. 2008, 46:1530-33. 10.1128/jcm.01964-07
  29. Cloud J, Noddin L, Pressman A, Hu M, Kelly C: Clostridium difficile strain NAP-1 is not associated with severe disease in a nonepidemic setting. Clin Gastroenterol Hepatol. 2009, 7:868-873.e2. 10.1016/j.cgh.2009.05.018
  30. Morgan OW, Rodrigues B, Elston T, Verlander NQ, Brown DF, Brazier J, Reacher M: Clinical severity of Clostridium difficile PCR ribotype 027: a case-case study. PLoS One. 2008, 3:e1812-10. 10.1371/journal.pone.0001812
  31. Walk ST, Micic D, Jain R, et al.: Clostridium difficile ribotype does not predict severe infection. Clin Infect Dis. 2012, 55:1661-68. 10.1093/cid/cis786
  32. Sirard S, Valiquette L, Fortier LC: Lack of association between clinical outcome of Clostridium difficile infections, strain type, and virulence-associated phenotypes. J Clin Microbiol. 2011, 49:4040-46. 10.1128/jcm.05053-11
  33. See I, Mu Y, Cohen J, et al.: NAP1 strain type predicts outcomes from Clostridium difficile infection. Clin Infect Dis. 2014, 58:1394-400. 10.1093/cid/ciu125
  34. Hubert B, Loo VG, Bourgault AM, et al.: A portrait of the geographic dissemination of the Clostridium difficile North American pulsed-field type 1 strain and the epidemiology of C. difficile-associated disease in Québec. Clin Infect Dis. 2007, 44:238-44. 10.1086/510391
  35. Hsu J, Abad C, Dinh M, Safdar N: Prevention of endemic healthcare-associated Clostridium difficile infection: reviewing the evidence. Am J Gastroenterol. 2010, 105:2327-39. 10.1038/ajg.2010.254
  36. Wilcox MH, Gerding DN, Poxton IR, et al.: Bezlotoxumab for prevention of recurrent Clostridium difficile infection. N Engl J Med. 2017, 376:305-17. 10.1056/nejmoa1602615
  37. FDA Approval of Bezlotoxumab in Prevention of Recurrent Clostridium difficile Infection. (2017). Accessed: January 12, 2019: http://www.jwatch.org/na43666/2017/04/24/fda-approval-bezlotoxumab-prevention-recurrent-clostridium.
  38. Secore S, Wang S, Doughtry J, et al.: Development of a novel vaccine containing binary toxin for the prevention of Clostridium difficile disease with enhanced efficacy against NAP1 strains. PLoS One. 2017, 12:e0170640. 10.1371/journal.pone.0170640
  39. Kokai-Kun JF, Roberts T, Coughlin O, et al.: The oral β-lactamase SYN-004 (ribaxamase) degrades ceftriaxone excreted into the intestine in phase 2a clinical studies. Antimicrob Agents Chemother. 2017, 61:pii: e02197-16. 10.1128/AAC.02197-16
  40. López-Ureña D, Quesada-Gómez C, Miranda E, Fonseca M, Rodríguez-Cavallini E: Spread of epidemic Clostridium difficile NAP1/027 in Latin America: case reports in Panama. J Med Microbiol. 2014, 63:322-24. 10.1099/jmm.0.066399-0
  41. Karlowsky JA, Adam HJ, Kosowan T, et al.: PCR ribotyping and antimicrobial susceptibility testing of isolates of Clostridium difficile cultured from toxin-positive diarrheal stools of patients receiving medical care in Canadian hospitals: the Canadian Clostridium difficile Surveillance Study (CAN-DIFF) 2013-2015. Diagn Microbiol Infect Dis. 2018, 91:105-11. 10.1016/j.diagmicrobio.2018.01.017
  42. Martínez-Meléndez A, Tijerina-Rodríguez L, Morfin-Otero R, et al.: Circulation of highly drug-resistant Clostridium difficile ribotypes 027 and 001 in two tertiary-care hospitals in Mexico. Microb Drug Resist. 2018, 24:386-92. 10.1089/mdr.2017.0323
  43. Coffman K, Chen XJC, Okamura C, Louie E: IVIG – A cure to severe refractory NAP-1 Clostridium difficile colitis? A case of successful treatment of severe infection, which failed standard therapy including fecal microbiota transplants and fidaxomicin. IDCases. 2017, 8:27-28. 10.1016/j.idcr.2017.03.002
  44. Vickers RJ, Tillotson GS, Nathan R, et al.: 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. Lancet Infect Dis. 2017, 17:735-44. 10.1016/S1473-3099(17)30235-9
  45. Louie T, Nord CE, Talbot GH, et al.: Multicenter, double-blind, randomized, phase 2 study evaluating the novel antibiotic, cadazolid, in patients with Clostridium difficile infection. Antimicrob Agents Chemother. 2015, 59:6266-73. 10.1128/AAC.00504-15
  46. Daley P, Louie T, Lutz JE, et al.: Surotomycin versus vancomycin in adults with Clostridium difficile infection: primary clinical outcomes from the second pivotal, randomized, double-blind, phase 3 trial. J Antimicrob Chemother. 2017, 72:3462-70. 10.1093/jac/dkx299
  47. Aziz M, Chandrasekar VT, Desai M, Fatima R, Jackson M, Sharma P: Sa1858 – surotomycin (a novel antibiotic) vs vancomycin for Clostridium difficile infection: a systematic review and meta analysis. Gastroenterology. 2018, 154:S421.

U.S. Food and Drug Administration (FDA) Grants Breakthrough Therapy Designation to Finch Therapeutics Investigational Drug CP101 for Treatment of Recurrent Clostridium difficile Infection (rCDI)

Finch Therapeutics Group, Inc., a clinical-stage microbiome therapeutics company, announced that the U.S. Food and Drug Administration (FDA) has granted Breakthrough Therapy Designation to investigational drug CP101 for the treatment of patients with recurrent Clostridium difficile (C. difficile) infection. Breakthrough Therapy Designation is intended to expedite the development and review of investigational therapeutics for serious or life-threatening conditions where preliminary clinical evidence indicates that the product may demonstrate a substantial improvement over existing therapies on one or more clinically significant endpoints.

Finch’s lead therapeutic candidate CP101 is designed to prevent recurrent C. difficile, a bacterial infection affecting over 500,000 patients each year and leading to an estimated 29,000 annual deaths. Recurrent C. difficile has been named an urgent public health threat by the Centers for Disease Control (CDC) and, with a high percentage of patients failing standard-of-care antibiotic treatment, presents a clear and urgent unmet medical need.

“We are thrilled that CP101 has been designated as a Breakthrough Therapy for recurrent C. difficile,” said Mark Smith, CEO of Finch. “CP101 is designed to break the cycles of infection by restoring the balance of the gut microbiome, an approach supported by numerous clinical studies and Finch’s extensive experience providing microbial treatments to patients suffering from C. difficile. This designation will accelerate our efforts to provide an effective therapy for patients living with this devastating infection, and we look forward to working closely with the FDA to advance that mission.”

Finch is actively enrolling patients with recurrent C. difficile in PRISM3, a randomized, placebo-controlled Phase II clinical study to assess the safety and efficacy of CP101. The study drug is an oral capsule that is administered in a single dose. For more information about this trial, please visit www.prism3trial.com.

CP101 is not approved in any country.The FDA’s Breakthrough Therapy Designation does not constitute or guarantee a future approval and does not alter the standards for approval.

About Finch Therapeutics Group, Inc.Finch Therapeutics Group, Inc. (Finch) is developing novel microbial therapies to serve patients with serious unmet medical needs. Built on 30 years of translational research at OpenBiome, MIT, University of Minnesota and the Center for Digestive Diseases, Finch uses  Human-First Discovery  to develop therapies from microbes that have demonstrated clinically significant impacts on patient outcomes. Finch is unique in having both a donor-derived  Full-Spectrum Microbiota  ( FSM ) product platform and a  Rationally Selected Microbiota  ( RSM ) product platform based on microbes grown in pure culture. Finch’s lead program, CP101, is an investigational  FSM  product for prevention of recurrent  C. difficile  infections. Finch’s  RSM  platform employs machine-learning algorithms to mine Finch’s unique clinical datasets, reverse engineering successful clinical experience to identify the key microbes driving patient outcomes. Finch has a strategic partnership with Takeda to develop FIN-524, an investigational  RSM  product for inflammatory bowel disease. Finch is using a rich foundation of clinical data to advance its pipeline, leveraging proof-of-principle results to evaluate target indications and inform the design of this new therapeutic class.

Full-Spectrum Microbiota, FSM, Rationally-Selected Microbiota, RSM, and Human-First Discovery are trademarks of Finch Therapeutics Group, Inc.

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C Diff Foundation Recognizes Rebiotix CEO Lee Jones with 2019 ‘Above and Beyond’ Award


C Diff Foundation Board presented Rebiotix CEO Lee Jones for Advocacy, Innovation in
C. difficile infection treatment

 

(NEW PORT RICHEY, Fla.) — The C. Diff Foundation Board of Directors announced that the 2019 “Above and Beyond” Award was presented to Rebiotix CEO Lee Jones in Roseville, Minnesota. The award, given to one recipient annually, is given to a person or organization that show extraordinary dedication to C. diff. patient safety, advocacy, and overall drive to improve the lives of those impacted by the infection.

“We are very proud to recognize Ms. Jones with our “Above and Beyond” award,” said C. Diff Foundation Founder and President, Nancy Caralla. “Lee’s dedication to the entire C.diff. community of patients, family members, and physicians hasn’t wavered since the founding of Rebiotix in 2011. She is a true example of what can happen when focusing on patient well-being drives new approaches to healthcare.”

The award was presented by the Foundation’s Vice President, Scott Battles at the Rebiotix office.

 

 

 

 

 

 

“It’s an honor to receive this award from the C. Diff Foundation,” said Ms. Jones. “The purpose of starting Rebiotix was to bring the power of the microbiome to the clinic in a scientifically sound, quality-controlled way to help patients. We stand with the Foundation in believing that patient well-being should be at the core of all that we do, from clinical trials to exploring new scientific landscapes within the microbiome space.”

About Rebiotix Inc.:

Rebiotix Inc., part of the Ferring Pharmaceuticals Group, is a late-stage clinical microbiome company focused on harnessing the power of the human microbiome to revolutionize the treatment of debilitating diseases. Rebiotix possesses a deep and diverse clinical pipeline, with its lead drug candidate, RBX2660, in Phase 3 clinical development for the prevention of recurrent Clostridium difficile (C. diff) infection. RBX2660 has been granted Fast Track, Orphan and Breakthrough Therapy designation from the FDA for its potential to prevent recurrent C. diff infection.

Rebiotix’s clinical pipeline also features RBX7455, a lyophilized, room temperature stable oral capsule formulation. Rebiotix is also targeting several other disease states with drug products built on its pioneering Microbiota Restoration Therapy(tm) platform. For more information on Rebiotix and its pipeline of human microbiome-directed therapies, visit https://www.rebiotix.com/

 

Researchers Present New Data that Brief NSAIDs Exposure Prior to a C.difficile Infection (CDI) Increases the Severity of the Infectious Colitis

ABSTRACT

Clostridium difficile infection (CDI) is a major public health threat worldwide. The use of nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with enhanced susceptibility to and severity of CDI; however, the mechanisms driving this phenomenon have not been elucidated. NSAIDs alter prostaglandin (PG) metabolism by inhibiting cyclooxygenase (COX) enzymes. Here, we found that treatment with the NSAID indomethacin prior to infection altered the microbiota and dramatically increased mortality and the intestinal pathology associated with CDI in mice. We demonstrated that in C. difficile-infected animals, indomethacin treatment led to PG deregulation, an altered proinflammatory transcriptional and protein profile, and perturbed epithelial cell junctions. These effects were paralleled by increased recruitment of intestinal neutrophils and CD4+ cells and also by a perturbation of the gut microbiota. Together, these data implicate NSAIDs in the disruption of protective COX-mediated PG production during CDI, resulting in altered epithelial integrity and associated immune responses.

IMPORTANCE Clostridium difficile infection (CDI) is a spore-forming anaerobic bacterium and leading cause of antibiotic-associated colitis. Epidemiological data suggest that use of nonsteroidal anti-inflammatory drugs (NSAIDs) increases the risk for CDI in humans, a potentially important observation given the widespread use of NSAIDs. Prior studies in rodent models of CDI found that NSAID exposure following infection increases the severity of CDI, but mechanisms to explain this are lacking. Here we present new data from a mouse model of antibiotic-associated CDI suggesting that brief NSAID exposure prior to CDI increases the severity of the infectious colitis. These data shed new light on potential mechanisms linking NSAID use to worsened CDI, including drug-induced disturbances to the gut microbiome and colonic epithelial integrity. Studies were limited to a single NSAID (indomethacin), so future studies are needed to assess the generalizability of our findings and to establish a direct link to the human condition.

INTRODUCTION

Clostridium difficile is the most commonly reported nosocomial pathogen in the United States and an urgent public health threat worldwide (1). C. difficile infection (CDI) manifests as a spectrum of gastrointestinal disorders ranging from mild diarrhea to toxic megacolon and/or death, particularly in older adults (2). The primary risk factor for CDI is antibiotic treatment, which perturbs the resident gut microbiota and abolishes colonization resistance (3). However, factors other than antibiotic exposure increase the risk for CDI and the incidence of cases not associated with the use of antimicrobials has been on the rise (4). Defining mechanisms whereby nonantibiotic factors impact CDI pathogenesis promises to reveal actionable targets for preventing or treating this infection.

Recently, several previously unappreciated immune system, host, microbiota, and dietary factors have emerged as modulators of CDI severity and risk. The food additive trehalose, for example, was recently shown to increase C. difficile virulence in mice, and the widespread adoption of trehalose in food products was implicated in the emergence of hypervirulent strains of C. difficile (5). Similarly, excess dietary zinc had a profound impact on severity of C. difficile disease in mice, and high levels of zinc altered the gut microbiota and increased susceptibility to CDI (6). Importantly, there is a growing body of evidence of the essential role of the innate immune response and inflammation in both protection against and pathology of CDI (79). Mounting a proper and robust inflammatory response is critical for successful clearance of C. difficile, and the immune response can be a key predictor of prognosis (3, 10). In this context, specific immune mediators can facilitate both protective and pathogenic responses through the activity of molecules such as interleukin-23 (IL-23) and IL-22, and an excessive and dysregulated immune response is believed to be one of the main factors behind postinfection complications.

Epidemiological data have established an association between the use of nonsteroidal anti-inflammatory drugs (NSAIDs) and CDI (11). Muñoz-Miralles and colleagues demonstrated that the NSAID indomethacin (Indo) significantly increased the severity of CDI in antibiotic-treated mice when the NSAID was applied following inoculation and throughout the infection (12), and indomethacin exposure is associated with alterations in the structure of the intestinal microbiota (13, 14). NSAIDs are among the most highly prescribed and most widely consumed drugs in the United States (15), particularly among older adults (16), and have been implicated in causing spontaneous colitis in humans (17, 18). They act by inhibiting cyclooxygenase (COX) enzymatic activity, which prevents the generation of prostaglandins (PGs) and alters the outcome of subsequent inflammatory events. Prostaglandins, especially PGE2, are important lipid mediators that are highly abundant at sites of inflammation and infection and that support gastrointestinal homeostasis and epithelial cell (EC) health (19). NSAID use has been associated with shifts in the gut microbiota, in both rodents and humans (2023), but these shifts have not been explored in the context of CDI.

In this report, we deployed a mouse model of antibiotic-associated CDI to examine the impact of exposure to indomethacin prior to infection with C. difficile on disease severity, immune response, intestinal epithelial integrity, and the gut microbiota. These investigations revealed that even a brief exposure to an NSAID prior to C. difficile inoculation dramatically increased CDI severity, reduced survival, and increased pathological evidence of disease. Inhibition of PG biosynthesis by indomethacin altered the cytokine response and immune cell recruitment following CDI, enhancing intestinal tissue histopathology and allowing partial systemic bacterial dissemination by dismantling intestinal epithelial tight junctions (TJs). Additionally, indomethacin treatment alone significantly perturbed the structure of the gut microbiota. These findings support epidemiological data linking NSAID use and CDI and caution against the overuse of NSAIDs in patients at high risk for C. difficile, such as older adults.

RESULTS

Indomethacin worsens C. difficile Infection in Mice and Increases Mortality.To determine the extent to which preexposure to NSAIDs influences the natural course of CDI, mice were treated with indomethacin for 2 days prior to inoculation with C. difficile (Fig. 1A). We infected C57BL/6 female mice with 1 × 104 spores of C. difficile NAP1/BI/027 strain M7404 following 5 days of pretreatment with a broad-spectrum antibiotic, cefoperazone (Fig. 1A). This brief indomethacin treatment prior to CDI dramatically decreased cecum size and increased the mortality rate from 20% to 80% (Fig. 1C) but did not significantly impact weight loss (Fig. 1D). Mice pretreated with indomethacin and infected with C. difficile also displayed histopathological evidence of more-severe cecal tissue damage compared to mice infected with C. difficile that were not exposed to the drug (Fig. 1E). Indomethacin-exposed and infected mice exhibited no change in the burden of C. difficile in the cecum (Fig. 1F), but their livers harbored significantly greater loads of mixed aerobic and anaerobic bacteria (Fig. 1G), suggesting that indomethacin pretreatment compromised intestinal barrier function during CDI and fostered microbiota translocation to the liver.

FIG 1

Indomethacin worsens the effects of C. difficile infection in mice. (A) C57BL/6 mice were treated with cefoperazone for 5 days followed by 2 days of recovery and then challenged by gavage with 1 × 104 spores of NAP1 strain M7404. Animals received 2 doses of 10 mg/kg of body weight of indomethacin by gavage daily as indicated by the top arrows. (B) Representative picture illustrating the macroscopic effects of the different treatments in the cecum. Indo, indomethacin; Abx, antibiotic; C. diff, C. difficile. (C to E) Mice were monitored for survival (Kaplan-Meier curve) (C), weight loss (D), and histopathologic severity of colitis (E) (n = 13 to 15/group). (F and G) C. difficile bacterial burden was evaluated in the ceca of 12 mice/group (F) and total aerobic bacterial burden plus anaerobic bacterial burden in the liver of 5 mice/group (G) also at day 3 after infection, with the discontinuous line indicating the limit of detection. Path., pathology. **, P < 0.01 (by log rank [Mantel-Cox] test for survival [panel C] and by unpaired t test for weights [panel D]); *, P < 0.05 (1-way analysis of variance [ANOVA] test for histopathological scores [panel E]); **, P < 0.01 (Wilcoxon test with Bonferroni correction [panel G]). I, indomethacin; A, antibiotic.

Indomethacin alters the proportions of neutrophils and CD4+ T cells in mucosal-associated tissues during C. difficile infection…………………………………

 

Damian Maseda, Joseph P. Zackular, Bruno Trindade, Leslie Kirk, Jennifer Lising Roxas, Lisa M. Rogers, Mary K. Washington, Liping Du, Tatsuki Koyama, V. K. Viswanathan, Gayatri Vedantam, Patrick D. Schloss, Leslie J. Crofford, Eric P. Skaar, David M. Aronoff
Jimmy D. Ballard, Editor

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