Novel Fidaxomicin Treatment Regimens for Patients With Multiple Clostridium difficile Infection Recurrences That Are Refractory to Standard Therapies

Pulsed dosing and extended daily dosing of oral vancomycin do not facilitate clearance of Clostridioides difficile colonization in mice

Vancomycin taper and pulse regimens are commonly used to treat recurrent Clostridioides difficile infections, but the mechanism by which these regimens might reduce recurrences is unclear. Here, we used a mouse model to test the hypothesis that pulse dosing of vancomycin after a 10-day treatment course enhances clearance of C. difficile from the intestinal tract. Mice with C. difficile colonization received 10 days of once-daily oral vancomycin followed by 20 days of treatment with saline (controls), daily vancomycin, or pulse dosing of vancomycin every 2 or 3 days. Stool samples were collected to measure the concentration of C. difficile during and after treatment, vancomycin concentrations, and growth of vegetative C. difficile during every 3 days dosing. Pulse dosing of vancomycin was not effective in maintaining suppression of C. difficile (P > 0.05 in comparison to saline controls); growth of vegetative C. difficile occurred between pulse doses when vancomycin decreased to undetectable levels. Daily dosing of vancomycin suppressed C. difficile during treatment, but recurrent colonization occurred after treatment in more than 75% of mice, and by post-treatment day 14, there was no significant difference among the control, pulse dosing, and daily dosing groups (P > 0.05). These findings demonstrate that pulse dosing of vancomycin every 2 or 3 days does not facilitate the clearance of C. difficile spores in mice. Studies are needed to examine the impact of vancomycin taper and pulsed regimens in patients.

Update on Clostridioides difficile Infection in Older Adults

Clostridioides difficile is a common cause of community-associated and health care-associated infections. Older adults are disproportionately affected, and long-term care facilities (LTCFs) have borne a substantial proportion of the burden of C difficile infection (CDI). Recurrences of CDI are common in older adults and have substantial adverse effects on quality of life. Appropriate diagnostic testing and management is essential for older adults in the community and in LTCFs. This review focuses on current concepts related to the epidemiology, diagnosis, and management of CDI in older adults.

Is Three Company or a Crowd? Comparing and Contrasting U.S. and European Clostridioidesdifficile Clinical Practice Guidelines

In 2021, the American College of Gastroenterology (ACG), the Infectious Diseases Society of America in conjunction with the Society for Healthcare Epidemiology of America (IDSA/SHEA), and the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) published updated clinical practice guidelines (CPGs) for the management of Clostridioides difficile infections. The differences, sometimes subtle, between these guideline recommendations have caused some debate among clinicians. This paper delves into select key recommendations from each respective CPG and analyzes the differences and evidence associated with each. One primary difference between the CPGs is the preference given to fidaxomicin over vancomycin for initial treatment in non-severe and severe disease endorsed by IDSA/SHEA and ESCMID guidelines, while the ACG-sponsored CPGs do not offer a preference. The emphasis on cost effective data was also a noticeable difference between the CPGs and thus interpretation of the available evidence. When using guidelines to help support local practice or institutional treatment pathways, clinicians should carefully balance CPG recommendations with local patient populations and feasibility of implementation, especially when multiple guidelines for the same disease state exist.

Clinical Practice Guideline by the Infectious Diseases Society of America (IDSA) and Society for Healthcare Epidemiology of America (SHEA): 2021 Focused Update Guidelines on Management of Clostridioides difficile Infection in Adults

This clinical practice guideline is a focused update on management of Clostridioides difficile infection (CDI) in adults specifically addressing the use of fidaxomicin and bezlotoxumab for the treatment of CDI. This guideline was developed by a multidisciplinary panel representing the Infectious Diseases Society of America (IDSA) and the Society for Healthcare Epidemiology of America (SHEA). This guideline is intended for use by healthcare professionals who care for adults with CDI, including specialists in infectious diseases, gastroenterologists, hospitalists, pharmacists, and any clinicians and healthcare providers caring for these patients. The panel's recommendations for the management CDI are based upon evidence derived from topic-specific systematic literature reviews. Summarized below are the recommendations for the management of CDI in adults. The panel followed a systematic process which included a standardized methodology for rating the certainty of the evidence and strength of recommendation using the GRADE approach (Grading of Recommendations Assessment, Development, and Evaluation). A detailed description of background, methods, evidence summary and rationale that support each recommendation, and knowledge gaps can be found online in the full text.

Clinical Practice Guideline by the Infectious Diseases Society of America (IDSA) and Society for Healthcare Epidemiology of America (SHEA): 2021 Focused Update Guidelines on Management of Clostridioides difficile Infection in Adults

This clinical practice guideline is a focused update on management of Clostridioides difficile infection (CDI) in adults specifically addressing the use of fidaxomicin and bezlotoxumab for the treatment of CDI. This guideline was developed by a multidisciplinary panel representing the Infectious Diseases Society of America (IDSA) and the Society for Healthcare Epidemiology of America (SHEA). This guideline is intended for use by healthcare professionals who care for adults with CDI, including specialists in infectious diseases, gastroenterologists, hospitalists, pharmacists, and any clinicians and healthcare providers caring for these patients. The panel's recommendations for the management CDI are based upon evidence derived from topic-specific systematic literature reviews.Summarized below are the recommendations for the management of CDI in adults. The panel followed a systematic process which included a standardized methodology for rating the certainty of the evidence and strength of recommendation using the GRADE approach (Grading of Recommendations Assessment, Development and Evaluation) (see Figure 1). A detailed description of background, methods, evidence summary and rationale that support each recommendation, and knowledge gaps can be found online in the full text.

Fecal Microbiota Transplantation for Recurrent C difficile Infection During the COVID-19 Pandemic: Experience and Recommendations

OBJECTIVE

To report experience with fecal microbiota transplantation (FMT) for recurrent Clostridioides difficile infection (rCDI) and provide recommendations for management of rCDI and donor testing during the COVID-19 pandemic.

METHODS

A retrospective study of patients with rCDI who underwent FMT from May 26, 2020, to September 30, 2020, with stool from well-screened donors with health and infectious screening and a newly implemented strategy for COVID-19 screening with every 2-week bookend testing with stool quarantine. Patients were followed up for development of rCDI and COVID-19.

RESULTS

Of the 57 patients who underwent FMT for rCDI, 29 were tested for COVID-19 via nasopharyngeal polymerase chain reaction (PCR) and 22 via serology. All results were negative, except for 1 positive serology. Donor testing every 2 weeks for COVID-19 via serology and nasopharyngeal swab PCR was negative, except for 2 donors at 1 center who were excluded. Three patients had rCDI after FMT, and 1 underwent repeat FMT. One patient developed respiratory symptoms suggestive of COVID-19 and tested negative via nasopharyngeal PCR. Eleven patients who underwent COVID-19 testing for elective procedures or hospitalizations tested negative. No SARS-CoV-2 transmission was noted.

CONCLUSIONS

With appropriate donor screening, FMT can be performed safely for rCDI during the COVID-19 pandemic. Development of a validated stool assay for SARS-CoV-2 will simplify this process further.

A Tapered-Pulsed Fidaxomicin Regimen following Treatment in Patients with Multiple Clostridioides difficile Infection Recurrences

We treated 46 patients with multiple recurrent Clostridioides difficile infections (mrCDI) using a tapered-pulsed (T-P) fidaxomicin regimen, the majority of whom failed prior T-P vancomycin treatment. Sustained clinical response rates at 30 and 90 days were 74% (34/46) and 61% (28/46). T-P fidaxomicin shows promise for management of mrCDI.

Clostridium difficile disease in solid organ transplant recipients: a recommended treatment paradigm

PURPOSE OF REVIEW

Organ transplant recipients have an increased incidence of Clostridium difficile disease and lower clinical response rates compared with the general population. Transplant specific treatment approaches are not defined. Therefore, a review of therapeutics in the transplant population is needed.

RECENT FINDINGS

A literature review on the current therapies for C. difficile was performed focusing on the evidence in transplant recipients and immunosuppressed populations.

SUMMARY

Transplant patients warrant an aggressive approach to treatment. The authors propose a suggested treatment paradigm for therapy.

Ridinilazole, a narrow spectrum antibiotic for treatment of Clostridioides difficile infection, enhances preservation of microbiota-dependent bile acids

Antibiotic treatment is a standard therapy for Clostridioides difficile infection, but dysbiosis of the gut microbiota due to antibiotic exposure is also a major risk factor for the disease. Following an initial episode of C. difficile infection, a relentless cycle of recurrence can occur, where persistent treatment-related dysbiosis predisposes the patient to subsequent relapse. This study uses a longitudinal study design to compare the effects of a narrow-spectrum (ridinilazole) or broad-spectrum antibiotic (vancomycin) on intestinal bile acid profiles and their associations with gut bacteria over the course of C. difficile infection treatment. At the end of treatment (day 10), subjects receiving vancomycin showed a nearly 100-fold increase in the ratio of conjugated to secondary bile acids in their stool compared with baseline, whereas subjects receiving ridinilazole maintained this ratio near baseline levels. Correlation analysis detected significant positive associations between secondary bile acids and several Bacteroidales and Clostridiales families. These families were depleted in the vancomycin group but preserved at near-baseline abundance in the ridinilazole group. Enterobacteriaceae, which expanded to a greater extent in the vancomycin group, correlated negatively and positively with secondary and conjugated primary bile acids, respectively. Bile acid ratios at the end of treatment were significantly different between those who recurred and those who did not. These results indicate that a narrow-spectrum antibiotic maintains an intestinal bile acid profile associated with a lowered risk of recurrence.NEW & NOTEWORTHY This is the first study to demonstrate in humans the relationships between Clostridioides difficile antibiotic treatment choice and bile acid metabolism both during therapy and after treatment cessation. The results show a microbiota- and metabolome-preserving property of a novel narrow-spectrum agent that correlates with the agent's favorable sustained clinical response rates compared with broad-spectrum antibiotic treatment.

Fecal microbiota transplantation for treatment of patients with recurrent Clostridioides difficile infection

INTRODUCTION

Recurrent Clostridiodes difficile infection (rCDI) is a growing public health burden, and is associated with poor patient outcomes. Fecal microbiota transplantation (FMT) is a novel therapy with an aim to restore the disrupted microbiota with demonstrated success in the management of rCDI and a favorable safety profile.

AREAS COVERED

This review includes a comprehensive overview of a search of the literature including epidemiology of rCDI, basics of the gut microbiome, antibiotic therapy for rCDI along with rationale for safety and efficacy of FMT for rCDI.

EXPERT OPINION

Patients exposed to risk factors, such as antimicrobial agents, are at risk for disruption of the gut microbiome resulting in the reduction of microbial diversity and dysbiosis. Dysbiotic microbiota predispose to primary and rCDI. Strategies to improve the current and future management of rCDI are under clinical investigation, including narrow-spectrum antibiotics, monoclonal antibodies and FMT, which has shown a high success rate for rCDI. Further investigation is needed to determine optimal standardization of the methodological components of FMT including donor screening, stool preparation, storage and instillation and patient follow-up. Newer methods of microbiota replacement therapies including enema- and capsule-based therapies are under investigation.

Strategies to prevent adverse outcomes following Clostridioides difficile infection in the elderly

Introduction: Clostridioides difficile remains the most common cause of healthcare-associated infections in the US, and it disproportionately affects the elderly. Older patients are more susceptible and have a greater risk of adverse outcomes from C. difficile infection (CDI), despite advances in treatment and prevention.Areas covered: The epidemiology and pathogenesis of CDI, as well as risk factors in the aging host, will be reviewed. The importance of antimicrobial stewardship and infection prevention in order to avoid acquisition and transmission will be discussed, as well as strategies to prevent adverse outcomes and recurrent CDI, through optimization of CDI treatment s,election.Expert opinion: Appropriate CDI-prevention strategies to avoid adverse outcomes in this susceptible population involve antimicrobial stewardship and methods to prevent C. difficile transmission in healthcare settings. Management strategies to prevent adverse outcomes include initiation of supportive therapy and proper selection of CDI specific treatments. Many patients may also benefit from adjunctive therapies or additional procedures.

Management of Clostridioides (formerly Clostridium) difficile infection (CDI) in solid organ transplant recipients: Guidelines from the American Society of Transplantation Community of Practice

These updated guidelines from the American Society of Transplantation Infectious Diseases Community of Practice address the prevention and management of Clostridium difficile infection in solid organ transplant (SOT) recipients. Clostridioides (formerly Clostridium) difficile infection (CDI) is among the most common hospital acquired infections. In SOT recipients, the incidence of CDI varies by type and number or organs transplanted. While a meta-analysis of published literature found the prevalence of postoperative CDI in the general surgical population to be approximately 0.51%, the prevalence of CDI that is seen in the solid organ transplant population ranges from a low of 3.2% in the pancreatic transplant population to 12.7% in those receiving multiple organ transplants. There are no randomized, controlled trials evaluating the management of CDI in the SOT population. Herein is a review and summary of the currently available literature that has been synthesized into updated treatment guidelines for the management of CDI in the SOT population.

Fecal microbiota transplantation (FMT) for C. difficile infection, just say 'No'

Despite lack of regulatory approval, fecal microbiota transplantation (FMT) is widely performed to manage C. difficile infection (CDI), particularly recurrent CDI. Herein, we critically review the available randomized controlled trials of FMT and address the following questions: Is FMT better than drug management of recurrent CDI?; Is FMT treatment per se or adjunctive treatment to antibiotics for CDI?; and, Is FMT safe? Finally, we elaborate non-FMT options for the management of recurrent CDI. Although promising, FMT should be reserved for patients who have failed appropriate antibiotic management of recurrent CDI.

Current and future trends in clostridioides (clostridium) difficile infection management

Current and future management of Clostridioides difficile infection (CDI) including antibiotic treatment is increasingly focused on preventive strategies, either prevention of recurrent CDI (rCDI) or primary prevention of CDI. In addition to newer narrow spectrum antibiotics and pulse dosing of antibiotic treatment, multiple widely differing approaches to prevention of CDI and rCDI are under clinical development or recently approved for clinical use. They include immunologics, both passive monoclonal antibodies and active vaccines targeted at C. difficile toxins, approaches to reduce antibiotic dysbiosis in the gut, microbiome restoration using fecal microbiome transplants (FMT) or biotherapeutic bacterial derivatives, and substitution of non-toxigenic C. difficile (NTCD) for toxigenic C. difficile. Newer antibiotics, monoclonal antibodies, and FMT are targeted at reducing rCDI whereas vaccines and reduction of antibiotic dysbiosis in the gut are targeted at prevention of primary CDI. Biotherapeutics may be used for prevention of either primary CDI or rCDI. Approaches such as monoclonal antibodies, FMT, and biotherapeutics provide rapid but transient preventive benefits, whereas vaccines require weeks to months to be effective, but will presumably provide long term prevention. More rapid but transient prevention strategies such as FMT and biotherapeutics could be used in combination with vaccines to provide both rapid and durable CDI prevention.

Fecal Microbiota Transplantation Is Superior to Fidaxomicin for Treatment of Recurrent Clostridium difficile Infection

BACKGROUND & AIMS

Fecal microbiota transplantation (FMT) is recommended for treatment of recurrent Clostridium difficile infection (rCDI). We performed a single-center randomized trial to compare the effects of FMT with those of fidaxomicin and vancomycin.

METHODS

We studied consecutive adults with rCDI seen at a gastroenterology clinic in Denmark from April 5, 2016 through June 10, 2018. Patients were randomly assigned to a group that received FMT, applied by colonoscopy or nasojejunal tube, after 4-10 days of vancomycin (125 mg 4 times daily; FMTv; n = 24), 10 days of fidaxomicin (200 mg twice daily; n = 24), or 10 days of vancomycin (125 mg 4 times daily; n = 16). Patients who had rCDI after this course of treatment and patients who could not be randomly assigned to groups were offered rescue FMTv. The primary outcome was combined clinical resolution and a negative result from a polymerase chain reaction test for Clostridium difficile (CD) toxin 8 weeks after the allocated treatment. Secondary end points included clinical resolution at week 8.

RESULTS

All 64 patients received their assigned treatment. The combination of clinical resolution and negative results from the test for CD were observed in 17 patients given FMTv (71%), 8 patients given fidaxomicin (33%), and 3 patients given vancomycin (19%; P = .009 for FMTv vs fidaxomicin; P = .001 for FMTv vs vancomycin; P = .31 for fidaxomicin vs vancomycin). Clinical resolution was observed in 22 patients given FMTv (92%), 10 patients given fidaxomicin (42%), and 3 patients given vancomycin (19%; P = .0002; P < .0001; P = .13). Results did not differ significantly between patients who received FMTv as their initial therapy and patients who received rescue FMTv. There was 1 serious adverse event that might have been related to FMTv.

CONCLUSIONS

In a randomized trial of patients with rCDI, we found the FMTv combination superior to fidaxomicin or vancomycin based on end points of clinical and microbiological resolution or clinical resolution alone. ClinicalTrials.gov, number NCT02743234; EudraCT, j.no 2015-003004-24.

Hypoalbuminemia as predictor of recurrence of Clostridium difficile infection

Background

Novel drugs for Clostridium difficile (C. difficile) infections have been proven to reduce recurrent infections. Because of their high financial costs, identification of patients at high risk for recurrence is essential to provide optimal treatment. The ATLAS score’s ability to predict 90-day recurrence, disease complications and 1‑year all-cause mortality was evaluated.

Methods

144 consecutive symptomatic patients with positive stool test for C. difficile were enrolled. The ATLAS score (consisting of the variables age, temperature, leukocyte count, albumin, systemic antibiotics, serum creatinine) was calculated and patients were stratified into 4 subgroups according to their scores. A Cox regression model was used to estimate the extent to which ATLAS was associated with 90-day recurrence. Furthermore, the score was correlated with disease complications and one-year all-cause mortality.

Results

ATLAS was unable to predict 90-day recurrence (p = 0.064, HR 1.134 [0.993;1.295]), but performed well for disease complications (D = 0.382, p < 0.001, HR 1.547 [1.266;1.889]) and mortality (p < 0.001, HR 1.374 [1.194;1.583]). Serum albumin was the only parameter able to predict 90-day recurrence (p = 0.016, HR 0.958 [0.926;0.992]) and was also a predictor of disease complications (p < 0.001, HR 0.865[0.809;0.924]) and one-year all-cause mortality (p < 0.001, HR 0.923 [0.896;0.950]). A threshold of 33.1g/L (sensitivity = 56%, specificity = 80%, AUC 0.683) and 29.2g/L (sensitivity = 75%, specificity = 70%, AUC 0.763) of serum albumin could be identified to be predictive for 90-day recurrence and one-year all-cause mortality, respectively.

Conclusions

Serum albumin and ATLAS are predictors of disease complications and mortality, while only serum albumin is significantly associated with 90-day disease recurrence.

Novel therapies and preventative strategies for primary and recurrent Clostridium difficile infections

Clostridium difficile is the leading infectious cause of antibiotic-associated diarrhea and colitis. C. difficile infection (CDI) places a heavy burden on the healthcare system, with nearly half a million infections yearly and an approximate 20% recurrence risk after successful initial therapy. The high incidence has driven new research on improved prevention such as the emerging use of probiotics, intestinal microbiome manipulation during antibiotic therapies, vaccinations, and newer antibiotics that reduce the disruption of the intestinal microbiome. While the treatment of acute C. difficile is effective in most patients, it can be further optimized by adjuvant therapies that improve the initial treatment success and decrease the risk of subsequent recurrence. Finally, the high risk of recurrence has led to multiple emerging therapies that target toxin activity, recovery of the intestinal microbial community, and elimination of latent C. difficile in the intestine. In summary, CDIs illustrate the complex interaction among host physiology, microbial community, and pathogen that requires specific therapies to address each of the factors leading to primary infection and recurrence.

Clostridioides difficile therapeutics: guidelines and beyond

Clostridioides difficile infection (CDI) has become an increasingly common infection both within and outside of the hospital setting. The management of this infection has been evolving as we learn more about the role of the human microbiota in protecting us from this gastrointestinal opportunist. For many years the focus of treatment had been on eradication of the vegetative, toxin-producing form of the organism, with little regard for its collateral impact on the host's microbiota or risk of recurrence. With the marked increase in C. difficile disease, and, particularly, recurrent disease in the last decade, new guidelines are more focused on targeting and reducing collateral damage to the colonic microbiota. Immune-based strategies that manipulate the microbiota and provide a humoral response to toxins have now become mainstream. Newer strategies are needed to look beyond simply resolving the primary episode but are focused on delayed outcomes such as cure at 90 days, reduced morbidity and mortality, and patient quality of life. The purpose of this review is to familiarize readers with the most recent evidence-based guidelines for C. difficile management, and to describe the role of newer antimicrobials, immunological-, and microbiota-based therapeutics to prevent recurrence and improve the outcomes of people with CDI.

Management of Clostridioides difficile colitis: insights for the gastroenterologist

Clostridioides difficile infection (CDI) is a common cause of diarrhea in both inpatient and outpatient settings. The last few years have seen major changes in the treatment spectrum of CDI, most notably, recommendations against using metronidazole for initial CDI, the addition of fidaxomicin and bezlotoxumab, and emergence of microbial replacement therapies. Several other therapies are undergoing clinical trials. This narrative review focuses on the treatment of CDI with a summary of literature on the newer modalities and the treatment guidelines issued by Infectious Diseases Society of America and European Society of Clinical Microbiology and Infectious Diseases.

Clostridium difficile in Older Adults

Recent increases in the incidence of Clostridium difficile infection (CDI) have been observed in all age groups, but the elderly have been disproportionately affected and long-term care facilities (LTCFs) have borne a significant proportion of the increasing burden. Recurrences are common in older adults and may have significant adverse effects on quality of life. Ensuring appropriate diagnostic testing and management is challenging for older adults in the community and in LTCFs. This review focuses on current concepts related to the epidemiology, diagnosis, and management of CDI in older adults.

Real-world use of fidaxomicin in a large UK tertiary hospital: how effective is it for treating recurrent disease?

All courses of fidaxomicin use in the study hospital were reviewed. It was used for first recurrence (six times), second recurrence (eight times) and one case of third recurrence. One patients received fidaxomicin as first-line treatment. Eight patients initially responded to therapy; of these, three patients were asymptomatic at 90 days, three patients remained asymptomatic at 30 days, and two patients had recurrences five and nine days after stopping therapy. Four patients failed to respond; of these, two patients required faecal transplantation and one patient required a colectomy. Two patients deteriorated and two patients died. Fidaxomicin was well tolerated. These findings suggest that the utility of fidaxomicin at this stage of infection is unclear.

Tapering Courses of Oral Vancomycin Induce Persistent Disruption of the Microbiota That Provide Colonization Resistance to Clostridium difficile and Vancomycin-Resistant Enterococci in Mice

Vancomycin taper regimens are commonly used for the treatment of recurrent Clostridium difficile infections. One rationale for tapering and pulsing of the dose at the end of therapy is to reduce the selective pressure of vancomycin on the indigenous intestinal microbiota. Here, we used a mouse model to test the hypothesis that the indigenous microbiota that provide colonization resistance against C. difficile and vancomycin-resistant enterococci (VRE) is repopulated during tapering courses of vancomycin. Mice were treated orally with vancomycin daily for 10 days, vancomycin in a tapering dose for 42 days, fidaxomicin for 10 days, or saline. To assess colonization resistance, subsets of mice were challenged with 10⁴ CFU of C. difficile or VRE at multiple time points during and after completion of treatment. The impact of the treatments on the microbiome was measured by cultures, real-time PCR for selected anaerobic bacteria, and deep sequencing. Vancomycin taper-treated mice developed alterations of the microbiota and disruption of colonization resistance that was persistent 18 days after treatment. In contrast, mice treated with a 10-day course of vancomycin exhibited recovery of the microbiota and of colonization resistance by 15 days after treatment, and fidaxomicin-treated mice maintained intact colonization resistance. These findings demonstrate that alteration of the indigenous microbiota responsible for colonization resistance to C. difficile and VRE persist during and after completion of tapering courses of vancomycin.

Cost-Effectiveness Analysis of Five Competing Strategies for the Management of Multiple Recurrent Community-Onset Clostridium difficile Infection in France

Background

Clostridium difficile infection (CDI) is characterized by high rates of recurrence, resulting in substantial health care costs. The aim of this study was to analyze the cost-effectiveness of treatments for the management of second recurrence of community-onset CDI in France.

Methods

We developed a decision-analytic simulation model to compare 5 treatments for the management of second recurrence of community-onset CDI: pulsed-tapered vancomycin, fidaxomicin, fecal microbiota transplantation (FMT) via colonoscopy, FMT via duodenal infusion, and FMT via enema. The model outcome was the incremental cost-effectiveness ratio (ICER), expressed as cost per quality-adjusted life year (QALY) among the 5 treatments. ICERs were interpreted using a willingness-to-pay threshold of €32,000/QALY. Uncertainty was evaluated through deterministic and probabilistic sensitivity analyses.

Results

Three strategies were on the efficiency frontier: pulsed-tapered vancomycin, FMT via enema, and FMT via colonoscopy, in order of increasing effectiveness. FMT via duodenal infusion and fidaxomicin were dominated (i.e. less effective and costlier) by FMT via colonoscopy and FMT via enema. FMT via enema compared with pulsed-tapered vancomycin had an ICER of €18,092/QALY. The ICER for FMT via colonoscopy versus FMT via enema was €73,653/QALY. Probabilistic sensitivity analysis with 10,000 Monte Carlo simulations showed that FMT via enema was the most cost-effective strategy in 58% of simulations and FMT via colonoscopy was favored in 19% at a willingness-to-pay threshold of €32,000/QALY.

Conclusions

FMT via enema is the most cost-effective initial strategy for the management of second recurrence of community-onset CDI at a willingness-to-pay threshold of €32,000/QALY.

A multi-center study of fidaxomicin use for Clostridium difficile infection

Purpose

Fidaxomicin use in real-world clinical practice, especially for severe Clostridium difficile infection (CDI), is mainly based on single-center observational studies. The purpose of this pharmacoepidemiology study was to assess outcomes of patients given fidaxomicin based on episode number and use of concomitant antibiotics.

Methods

Fidaxomicin use over time across included hospitals in the United States was assessed using a large inpatient drug utilization database. A multicenter retrospective chart review was also conducted of hospitalized patients with CDI that received fidaxomicin between 2011 and 2013. Fidaxomicin utilization and clinical outcomes were stratified by use of fidaxomicin for first or second episode (early episodes) versus greater than or equal to episodes (later episodes).

Results

The overall fidaxomicin use rate was 2.16 % which increased from 0.22 % in the last two quarters of 2011 to 3.16 % in the first two quarters of 2013. A total of 102 hospitalized patients that received fidaxomicin from 11 hospitals were identified in the multicenter study. Sixty-nine patients received fidaxomicin for early (68 % with severe CDI) and 33 received for later episodes. The majority of patients received other CDI therapy including 61 patients (88 %) for early episodes and 27 (82 %) for later episodes. Concomitant non-CDI antibiotics were received by 48 patients (47 %). Rates of clinical outcomes were similar regardless of CDI episode.

Conclusion

This study demonstrated a slow but steady increase in fidaxomicin utilization over time; most of which was combined with other systemic antibiotics. Antimicrobial stewardship teams should provide guidance on appropriate use of fidaxomicin to optimize therapy and assess the need to continue other antibiotics during CDI treatment.

Fidaxomicin: A novel agent for the treatment of Clostridium difficile infection

Oral vancomycin and oral metronidazole have several limitations with regard to their use in the treatment of Clostridium difficile infections (CDIs); however, oral vancomycin has been considered the gold standard in clinical trials. In June 2012, fidaxomicin received Health Canada approval for the treatment of CDIs. Its chemistry, mechanisms of action and pharmacological properties are discussed, along with its potential role in CDI therapy.

BACKGROUND:

Due to the limitations of existing treatment options for Clostridium difficile infection (CDI), new therapies are needed.

OBJECTIVE:

To review the available data on fidaxomicin regarding chemistry, mechanisms of action and resistance, in vitro activity, pharmacokinetic and pharmacodynamic properties, efficacy and safety in clinical trials, and place in therapy.

METHODS:

A search of PubMed using the terms “fidaxomicin”, “OPT-80”, “PAR-101”, “OP-1118”, “difimicin”, “tiacumicin” and “lipiarmycin” was performed. All English-language articles from January 1983 to November 2014 were reviewed, as well as bibliographies of all articles.

RESULTS:

Fidaxomicin is the first macrocyclic lactone antibiotic with activity versus C difficile. It inhibits RNA polymerase, therefore, preventing transcription. Fidaxomicin (and its active metabolite OP-1118) is bactericidal against C difficile and exhibits a prolonged postantibiotic effect (approximately 10 h). Other than for C difficile, fidaxomicin demonstrated only moderate inhibitory activity against Gram-positive bacteria and was a poor inhibitor of normal colonic flora, including anaerobes and enteric Gram-negative bacilli. After oral administration (200 mg two times per day for 10 days), fidaxomicin achieved low serum concentration levels but high fecal concentration levels (mean approximately 1400 μg/g stool). Phase 3 clinical trials involving adults with CDI demonstrated that 200 mg fidaxomicin twice daily for 10 days was noninferior to 125 mg oral vancomycin four times daily for 10 days in regard to clinical response at the end of therapy. Fidaxomicin was, however, reported to be superior to oral vancomycin in reducing recurrent CDI and achieving a sustained clinical response (assessed at day 28) for patients infected with non-BI/NAP1/027 strains.

CONCLUSION:

Fidaxomicin was noninferior to oral vancomycin with regard to clinical response at the end of CDI therapy. Fidaxomicin has been demonstated to be as safe as oral vancomycin, but superior to vancomycin in achieving a sustained clinical response for CDI in patients infected with non-BI/NAP1/027 strains. Caution should be exercised in using fidaxomicin monotherapy for treatment of severe complicated CDI because limited data are available. Whether fidaxomicin is cost effective (due to its significantly higher acquisition cost versus oral vancomycin) depends on the acceptable willingness to pay threshold per quality-adjusted life year as a measure of assessing cost effectiveness.

Clinical and Healthcare Burden of Multiple Recurrences of Clostridium difficile Infection

BACKGROUND

Clostridium difficile infection (CDI) is associated with a high risk of recurrence (rCDI). Few studies have focused on multiple recurrences. To evaluate the potential of novel treatments targeting recurrence, we assessed the burden and severity of rCDI.

METHODS

This was a retrospective cohort of adults diagnosed with CDI in a hospital in Sherbrooke, Canada (1998-2013). An rCDI episode was defined by the reappearance of diarrhea leading to a treatment, with or without a positive toxin assay, within 14-60 days after the previous episode.

RESULTS

We included 1527 patients. The probability of developing a first rCDI was 25% (354/1418); a second, 38% (128/334); a third, 29% (35/121); and a fourth or more, 27% (9/33). Two or more rCDIs were observed in 9% (128/1389) of patients. The risk of a first recurrence fluctuated over time, but there was no such variation for second or further recurrences. The proportion of severe cases decreased (47% for initial episodes, 31% for first recurrences, 25% for second, 17% for third), as did the risk of complicated CDI (5.8% to 2.8%). The severity and risk of complications of first recurrences decreased over time, while oral vancomycin was used more systemically. A hospital admission was needed for 34% (148/434) of recurrences.

CONCLUSIONS

This study documented the clinical and healthcare burden of rCDI: 34% of patients with rCDI needed admission, 28% developed severe CDI, and 4% developed a complication. Secular changes in the severity of recurrences could reflect variations in the predominant strain, or better management.

The Antimicrobial Stewardship Approach to Combating Clostridium Difficile

Clostridium difficile remains a major public health threat and continues to contribute to excess morbidity, mortality and healthcare costs. Antimicrobial stewardship programs have demonstrated success in combating C. difficile, primarily through antibiotic restrictive strategies. As the incidence and prevalence of C. difficile associate disease continues to increase both in the hospital and community setting, additional stewardship approaches are needed. This manuscript reviews stewardship interventions that have been successful against C. difficile associated disease and proposes future tactics that antimicrobial stewardship programs may employ to develop a more global approach to combat this difficult pathogen.