Microbiota-based markers predictive of development of Clostridioides difficile infection

Antibiotic-induced modulation of the intestinal microbiota can lead to Clostridioides difficile infection (CDI), which is associated with considerable morbidity, mortality, and healthcare-costs globally. Therefore, identification of markers predictive of CDI could substantially contribute to guiding therapy and decreasing the infection burden. Here, we analyze the intestinal microbiota of hospitalized patients at increased CDI risk in a prospective, 90-day cohort-study before and after antibiotic treatment and at diarrhea onset. We show that patients developing CDI already exhibit significantly lower diversity before antibiotic treatment and a distinct microbiota enriched in Enterococcus and depleted of Ruminococcus, Blautia, Prevotella and Bifidobacterium compared to non-CDI patients. We find that antibiotic treatment-induced dysbiosis is class-specific with beta-lactams further increasing enterococcal abundance. Our findings, validated in an independent prospective patient cohort developing CDI, can be exploited to enrich for high-risk patients in prospective clinical trials, and to develop predictive microbiota-based diagnostics for management of patients at risk for CDI

Incidence and predictive biomarkers of Clostridioides difficile infection in hospitalized patients receiving broad-spectrum antibiotics

Trial enrichment using gut microbiota derived biomarkers by high-risk individuals can improve the feasibility of randomized controlled trials for prevention of Clostridioides difficile infection (CDI). Here, we report in a prospective observational cohort study the incidence of CDI and assess potential clinical characteristics and biomarkers to predict CDI in 1,007 patients ≥ 50 years receiving newly initiated antibiotic treatment with penicillins plus a beta- lactamase inhibitor, 3rd/4th generation cephalosporins, carbapenems, fluoroquinolones or clindamycin from 34 European hospitals. The estimated 90-day cumulative incidences of a first CDI episode is 1.9% (95% CI 1.1-3.0). Carbapenem treatment (Hazard Ratio (95% CI): 5.3 (1.7-16.6)), toxigenic C. difficile rectal carriage (10.3 (3.2-33.1)), high intestinal abundance of Enterococcus spp. relative to Ruminococcus spp. (5.4 (2.1-18.7)), and low Shannon alpha diversity index as determined by 16 S rRNA gene profiling (9.7 (3.2-29.7)), but not nor- malized urinary 3-indoxyl sulfate levels, predicts an increased CDI risk

High acquisition rate of extended-spectrum β-lactamase-producing Enterobacteriaceae among French military personnel on mission abroad, without evidence of inter-individual transmission

International audienceOBJECTIVES:Acquisition of extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) by Europeans travelling individually in high-endemicity countries is common. However, how the different ESBL-E strains circulate in groups of travellers has not been studied. We investigated ESBL-E transmission within several groups of French military personnel serving overseas for 4-6 months.METHODS:We conducted a prospective study among French military personnel assigned to Afghanistan, French Guiana or Côte d'Ivoire for 4-6 months. Faecal samples provided by volunteers before leaving and after returning were screened for ESBL-E isolates. ESBL Escherichia coli from each military group was characterized by repetitive element palindromic polymerase chain reaction (rep-PCR) fingerprinting followed, in the Afghanistan group, by whole-genome sequencing (WGS) if similarity was ≥97%.RESULTS:Among the 189 volunteers whose samples were negative before departure, 72 (38%) were positive after return. The highest acquisition rates were observed in the Afghanistan (29/33, 88%) and Côte d'Ivoire (39/80, 49%) groups. Acquisition rates on return from French Guiana were much lower (4/76, 5%). WGS of the 20 strains from the Afghanistan group that clustered by rep-PCR identified differences in sequence type, serotype, resistance genes and plasmid replicons. Moreover, single-nucleotide polymorphism (SNP) differences across acquired strains from a given cluster ranged from 30 to 3641, suggesting absence of direct transmission.CONCLUSIONS:ESBL-E. coli acquisition was common among military personnel posted overseas. Many strains clustered by rep-PCR but differed by WGS and SNP analysis, suggesting acquisition from common external sources rather than direct person-to-person transmission

An open randomized multicentre Phase 2 trial to assess the safety of DAV132 and its efficacy to protect gut microbiota diversity in hospitalized patients treated with fluoroquinolones

Background DAV132 (colon-targeted adsorbent) has prevented antibiotic-induced effects on microbiota in healthy volunteers. Objectives To assess DAV132 safety and biological efficacy in patients. Patients and methods An open-label, randomized [stratification: fluoroquinolone (FQ) indication] multicentre trial comparing DAV132 (7.5 g, 3 times a day, orally) with No-DAV132 in hospitalized patients requiring 5-21 day treatment with FQs and at risk of Clostridioides difficile infection (CDI). FQ and DAV132 were started simultaneously, DAV132 was administered for 48 h more, and patients were followed up for 51 days. The primary endpoint was the rate of adverse events (AEs) independently adjudicated as related to DAV132 and/or FQ. The planned sample size of 260 patients would provide a 95% CI of +/- 11.4%, assuming a 33% treatment-related AE rate. Plasma and faecal FQ concentrations, intestinal microbiota diversity, intestinal colonization with C. difficile, MDR bacteria and yeasts, and ex vivo resistance to C. difficile faecal colonization were assessed. Results Two hundred and forty-three patients (median age 71 years; 96% with chronic comorbidity) were included (No-DAV132, n = 120; DAV132, n = 123). DAV132- and/or FQ-related AEs did not differ significantly: 18 (14.8%) versus 13 (10.8%) in DAV132 versus No-DAV132 patients (difference 3.9%; 95% CI: -4.7 to 12.6). Day 4 FQ plasma levels were unaffected. DAV132 was associated with a >98% reduction in faecal FQ levels (Day 4 to end of treatment; P < 0.001), less impaired microbiota diversity (Shannon index; P = 0.003), increased ex vivo resistance to C. difficile colonization (P = 0.0003) and less frequent FQ-induced VRE acquisition (P = 0.01). Conclusions In FQ-treated hospitalized patients, DAV132 was well tolerated, and FQ plasma concentrations unaffected. DAV132 preserved intestinal microbiota diversity and C. difficile colonization resistance

Efficacy and safety of a phospholipid emulsion (GR270773) in Gram-negative severe sepsis: Results of a phase II multicenter, randomized, placebo-controlled, dose-finding clinical trial

Objective: To assess the survival benefit and safety profile of low-dose (850 mg/kg) and high-dose (1350 mg/kg) phospholipid emulsion vs. placebo administered as a continuous 3-day infusion in patients with confirmed or suspected Gram-negative severe sepsis. Preclinical and ex vivo studies show that lipoproteins bind and neutralize endotoxin, and experimental animal studies demonstrate protection from septic death when lipoproteins are administered. Endotoxin neutralization correlates with the amount of phospholipid in the lipoprotein particles. Design: A three-arm, randomized, blinded, placebo-controlled trial. Setting: Conducted at 235 centers worldwide between September 2004 and April 2006. Padents: A total of 1379 patients participated in the study, 598 patients received low-dose phospholipid emulsion, and 599 patients received placebo. The high-dose phospholipid emulsion arm was stopped, on the recommendation of the Independent Data Monitoring Committee, due to an increase in life-threatening serious adverse events at the fourth interim analysis and included 182 patients. Measurements and Main Results: A 28-day all-cause mortality and new-onset organ failure. There was no significant treatment benefit for low- or high-dose phospholipid emulsion vs. placebo for 28-day all-cause mortality, with rates of 25.8% (p =.329), 31.3% (p =.879), and 26.9%, respectively. The rate of new-onset organ failure was not statistically different among groups at 26.3%, 31.3%, 20.4% with low- and high-dose phospholipid emulsion, and placebo, respectively (one-sided p =.992, low vs. placebo; p =.999, high vs. placebo). Of the subjects treated, 45% had microbiologically confirmed Gram-negative infections. Maximal changes in mean hemoglobin levels were reached on day 10 (-1.04 g/dL) and day 5 (-1.36 g/dL) with low- and high-dose phospholipid emulsion, respectively, and on day 14 (-0.82 g/dl-) with placebo. Conclusions: Treatment with phospholipid emulsion did not reduce 28-day all-cause mortality, or reduce the onset of new organ failure in patients with suspected or confirmed Gram-negative severe sepsis

Protection of the Human Gut Microbiome From Antibiotics

MAJOR ARTICLE Clinical Trials Registration: NCT02176005International audienceBackground:Antibiotics are life-saving drugs but severely affect the gut microbiome with short-term consequences including diarrhea and selection of antibiotic-resistant bacteria. Long-term links to allergy and obesity are also suggested. We devised a product, DAV132, and previously showed its ability to deliver a powerful adsorbent, activated charcoal, in the late ileum of human volunteers.Methods:We performed a randomized controlled trial in 28 human volunteers treated with a 5-day clinical regimen of the fluoroquinolone antibiotic moxifloxacin in 2 parallel groups, with or without DAV132 coadministration. Two control goups of 8 volunteers each receiving DAV132 alone, or a nonactive substitute, were added.Results:The coadministration of DAV132 decreased free moxifloxacin fecal concentrations by 99%, while plasmatic levels were unaffected. Shotgun quantitative metagenomics showed that the richness and composition of the intestinal microbiota were largely preserved in subjects co-treated with DAV132 in addition to moxifloxacin. No adverse effect was observed. In addition, DAV132 efficiently adsorbed a wide range of clinically relevant antibiotics ex vivo.Conclusions:DAV132 was highly effective to protect the gut microbiome of moxifloxacin-treated healthy volunteers and may constitute a clinical breakthrough by preventing adverse health consequences of a wide range of antibiotic treatments.Clinical Trials Registration:NCT02176005

DAV132, an Adsorbent-Based Product, Protects the Gut Microbiome and Prevents Clostridium difficile Infections During Moxifloxacin Treatments

International audienceBackground. During antibiotic treatments, antibiotics reach the colon and alter the microbiome, resulting in emergence and dissemination of resistant bacteria, antibiotic-associated diarrhea (AAD) and occurrence of Clostridium difficile (Cd) infections (CDI). We developed an oral adsorbent-based product, DAV132, to be co-administered with antibiotics in order to prevent these effects. We report here the results of protection of the microbiome in human volunteers treated with oral moxifloxacin (MOX), and protection against CDI in vitro in a human gut model (HGM) and in vivo in experimental hamsters.Methods. Four groups (MOX [400 mg OD for 5 days], MOX + DAV132 [7.5 g TID for 7 days], DAV132, or control) of healthy volunteers (n = 44) were included in a randomized clinical trial. Feces were collected at screening, daily from D1 to D9 and at D12, D16, D23, D30, D37 and plasma PK assayed at D1and5. Metagenomic analyses were done by shotgun sequencing at screening, D3, D6, D9, D16 and D37. The effect of DAV132 on MOX was also assessed in a HGM inoculated with Cd spores (ribotype 027, MOX MIC 32 mg/L); bacterial counts, toxin production and MOX concentrations were measured over time. MOX dosed hamsters were inoculated with 104 spores of a non-epidemic Cd (TcdA + , TcdB + , cdtB−) and treated ±DAV132. Mortality and Cd counts were assessed over time.Results. In humans, DAV132 was well tolerated and decreased free fecal MOX by > 99% compared to MOX alone: ratio of mean LogAUCD1-D16 = 0.0093 (95% CI 0.0061-0.0144), p = 0.03 × 10−16; MOX plasma PK was not changed significantly. Alterations of the fecal microbiome observed with MOX were prevented. In the HGM, DAV protected the microbiota and prevented Cd overgrowth and toxin production. Hamsters were fully protected by DAV against MOX-induced CDI (dose dependent), with decreased free fecal MOX and Cd counts.Conclusion. DAV132 protects humans against fecal microbiome disruption after oral MOX treatment, without altering its plasma PK. In vitro results in HGM and in vivo results in hamsters suggest that DAV132 should be protective against antibiotic-induced CDI. These results warrant further clinical development of DAV132 to protect the intestinal microbiota, and so prevent AAD and CDI, in patients receiving oral or parenteral antibiotics