Effects of Thiopurine Withdrawal on Vedolizumab-Treated Patients With Ulcerative Colitis: A Randomized Controlled Trial.

BACKGROUND & AIMS: The impact of thiopurine de-escalation while on vedolizumab versus continuing thiopurine therapy in ulcerative colitis (UC) is unclear. We aimed to determine the effect of thiopurine withdrawal for patients with UC in remission on vedolizumab. METHODS: This multicenter randomized controlled trial recruited UC patients on vedolizumab 300 mg intravenously every 8 weeks and a thiopurine. Patients in steroid-free clinical remission for ≥6 months and endoscopic remission/improvement (Mayo endoscopic subscore ≤1) were randomized 2:1 to withdraw or continue thiopurine. Primary outcome was comparing week 48 vedolizumab trough concentrations. Secondary outcomes were clinical relapse (partial Mayo score ≥3 and fecal calprotectin >150 µg/g or increase in Mayo endoscopic subscore ≥1 from baseline), fecal calprotectin remission (<150 µg/g), C-reactive protein remission (<5 mg/L), centrally read endoscopic remission (Mayo endoscopic subscore = 0), histologic remission (Nancy index = 0), histo-endoscopic remission, and adverse events. RESULTS: In total, 62 patients were randomized to continue (n = 20) or withdraw (n = 42) thiopurine. At week 48, vedolizumab trough concentrations were not significantly different between continue and withdrawal groups (14.7 µg/mL, interquartile rate [IQR], 12.3-18.5 µg/mL versus 15.9 µg/mL, IQR, 10.1-22.7 µg/mL, respectively, P = 0.36). The continue group had significantly higher fecal calprotectin remission (95.0%, 19/20 versus 71.4%, 30/42; P = .03), histologic remission (80.0%, 16/20 versus 48.6%, 18/37; P = .02), and histo-endoscopic remission (75.0%, 15/20 versus 32.4%, 12/37; P = .002) than the withdrawal group. Histologic activity (hazard ratio [HR], 15.5; 95% confidence interval [CI], 1.6-146.5; P = .02) and prior anti-tumor necrosis factor exposure (HR, 6.5; 95% CI, 1.3-33.8; P = .03) predicted clinical relapse after thiopurine withdrawal. CONCLUSIONS: Thiopurine withdrawal did not affect vedolizumab trough concentrations. However, it may increase fecal calprotectin, histologic, and histo-endoscopic activity. Histologic activity and prior anti-tumor necrosis factor exposure may predict disease relapse on thiopurine withdrawal for patients using vedolizumab for UC. Australian and New Zealand Trial Registry, number ACTRN12618000812291.

Biological Agents in the Treatment of Crohn's Disease: A Propensity Score-Matched Analysis From the Prospective Persistence Australian National IBD Cohort (PANIC3) Study.

INTRODUCTION: Comparative effectiveness research provides data on the relative benefits and risks between treatments. In Crohn's disease (CD), however, there are few head-to-head studies comparing advanced therapies and none with long-term follow-up. Real-world effectiveness, defined by treatment persistence, obtained from prospective population-based patient cohorts, may help determine the best sequencing and positioning of biological agents. METHODS: We analyzed the prospectively collected population-based Australian national Pharmaceutical Benefits Scheme dispensing data registry (2005-2019) for CD. There is no mandated biological agent prescribing order, and all citizens and permanent residents are eligible for treatment irrespective of insurance status. Propensity score matching was performed to reduce selection bias. RESULTS: There were 2,029 lines of therapy in 1,446 patients (median age 43 years, interquartile range 34-58, 44% male patients) over the 15-year period with 5,618 patient-years of follow-up. Per line of therapy, 915/2,029 (45.1%) patients used adalimumab, 722/2,029 (35.6%) used infliximab, 155/2,029 (7.6%) used vedolizumab, and 237/2,029 (11.7%) used ustekinumab. When used in biological agent-naive patients, there was no difference in persistence between any agent ( P > 0.05). Used after first line in biological agent-experienced CD, ustekinumab had significantly better persistence than non-ustekinumab biological agents ( P = 0.0018), vs anti-tumor necrosis factor (TNF) alpha therapy ( P = 0.006) or vedolizumab ( P < 0.001). Ustekinumab persistence was unaffected by prior biological agent exposure ( P = 0.51). After anti-TNF use, ustekinumab had superior persistence to an alternative anti-TNF agent ( P = 0.033) and to vedolizumab ( P = 0.026). Using a propensity score-matched analysis adjusted for age, immunomodulator use, and bio-exposed status, ustekinumab had superior persistence to anti-TNF ( P = 0.01). Multivariate predictors of worse persistence were the use of a non-ustekinumab biological agent (adjusted hazard ratio 2.10, P < 0.001), and bio-experienced status (adjusted hazard ratio 1.23, P < 0.001). DISCUSSION: This large national prospective database with nonhierarchical prescribing of biological agents did not identify superior persistence of any agent in bio-naive CD. However, for patients with bio-experienced CD, persistence was greater with ustekinumab.

The first international Rome consensus conference on gut microbiota and faecal microbiota transplantation in inflammatory bowel disease.

BACKGROUND: Several randomised clinical trials (RCTs) performing faecal microbiota transplantation (FMT) for the management of inflammatory bowel disease (IBD), particularly for ulcerative colitis, have recently been published, but with major variations in study design. These include differences in administered dose, route and frequency of delivery, type of placebo and evaluated endpoints. Although the overall outcomes appear to be promising, they are highly dependent on both donor and recipient factors. OBJECTIVE: To develop concensus-based statements and recommendations for the evaluation, management and potential treatment of IBD using FMT in order to move towards standardised practices. DESIGN: An international panel of experts convened several times to generate evidence-based guidelines by performing a deep evaluation of currently available and/or published data. Twenty-five experts in IBD, immunology and microbiology collaborated in different working groups to provide statements on the following key issues related to FMT in IBD: (A) pathogenesis and rationale, (B) donor selection and biobanking, (C) FMT practices and (D) consideration of future studies and perspectives. Statements were evaluated and voted on by all members using an electronic Delphi process, culminating in a plenary consensus conference and generation of proposed guidelines. RESULTS AND CONCLUSIONS: Our group has provided specific statements and recommendations, based on best available evidence, with the end goal of providing guidance and general criteria required to promote FMT as a recognised strategy for the treatment of IBD.

Defined microbiota transplant restores Th17/RORγt+ regulatory T cell balance in mice colonized with inflammatory bowel disease microbiotas.

The building evidence for the contribution of microbiota to human disease has spurred an effort to develop therapies that target the gut microbiota. This is particularly evident in inflammatory bowel diseases (IBDs), where clinical trials of fecal microbiota transplantation have shown some efficacy. To aid the development of novel microbiota-targeted therapies and to better understand the biology underpinning such treatments, we have used gnotobiotic mice to model microbiota manipulations in the context of microbiotas from humans with inflammatory bowel disease. Mice colonized with IBD donor-derived microbiotas exhibit a stereotypical set of phenotypes, characterized by abundant mucosal Th17 cells, a deficit in the tolerogenic RORγt+ regulatory T (Treg) cell subset, and susceptibility to disease in colitis models. Transplanting healthy donor-derived microbiotas into mice colonized with human IBD microbiotas led to induction of RORγt+ Treg cells, which was associated with an increase in the density of the microbiotas following transplant. Microbiota transplant reduced gut Th17 cells in mice colonized with a microbiota from a donor with Crohn's disease. By culturing strains from this microbiota and screening them in vivo, we identified a specific strain that potently induces Th17 cells. Microbiota transplants reduced the relative abundance of this strain in the gut microbiota, which was correlated with a reduction in Th17 cells and protection from colitis.

Microbial determinants of effective donors in faecal microbiota transplantation for UC.

OBJECTIVE: Faecal microbiota transplantation (FMT) has variable efficacy in treating UC. Recently, oral lyophilised FMT was found to induce remission in patients with UC, with one donor having 100% efficacy compared with a second donor (36% efficacy). We characterised differences in the gut microbiota of these two donors with the aim of improving FMT donor selection. DESIGN: Faecal samples from the two donors were collected over a period of 44 (donor 1) or 70 (donor 2) weeks. The microbiome and metabolome were profiled using shotgun metagenomics and untargeted metabolomics RESULTS: Gut microbiome long-term stability was highly evident in the effective donor. Donor microbiota species evenness was a robust feature associated with clinical efficacy across two clinical trials of FMT in UC, leading to increased donor species engraftment in patients. Alpha diversity and beta diversity of donor gut microbiotas significantly differed. 90 bacterial species and one archaeon were differentially abundant between donors, 44 of which were >0.1% in relative abundance. 17/44 species were enriched in the effective donor, 11 of which (64.7%) were assembled into high-quality genomes that were prevalent (≥75% samples) in that donor, and six showed evidence of engraftment in patients. Taxonomic differences between donors translated to substantial microbial functional differences that were validated using metabolomics. CONCLUSION: Donor microbiota stability and species evenness were identified as novel metrics that were associated with therapeutic efficacy in UC, beyond individual microbial species or metabolites. These metrics may represent community resilience that translates to better engraftment in the host. TRIAL REGISTRATION NUMBER: ACTRN12619000611123.

An update on fecal microbiota transplantation for the treatment of gastrointestinal diseases.

Our understanding of the microbiome and its implications for human health and disease continues to develop. Fecal microbiota transplantation (FMT) is now an established treatment for recurrent Clostridioides difficile infection. There is also increasing evidence for the efficacy of FMT in inducing remission for mild-moderate ulcerative colitis. However, for other indications, data for FMT are limited, with randomized controlled trials rare, typically small and often conflicting. Studies are continuing to explore the role of FMT for many other conditions, including Crohn's disease, functional gut disorders, metabolic syndrome, modulating responses to chemotherapy, eradication of multidrug resistant organisms, and the gut-brain axis. In light of safety, logistical, and regulatory challenges, there is a move to standardized products including narrow spectrum consortia. However, the mechanisms underpinning FMT remain incompletely understood, including the role of non-bacterial components, which may limit success of novel microbial approaches.

The diagnostic yield of pan-enteric capsule endoscopy in inflammatory bowel disease: A systematic review and meta-analysis.

BACKGROUND AND AIM: Capsule endoscopy (CE) is a non-invasive diagnostic modality enabling real time video imaging of the gastrointestinal (GI) mucosa. Pan-enteric capsule endoscopy (PCE) is now able to thoroughly assess the entire GI tract, including for inflammatory bowel disease (IBD). Our aim was to evaluate the diagnostic accuracy of PCEs in IBD. METHODS: We comprehensively searched electronic databases (MEDLINE, SCOPUS, EMBASE, and Cochrane Central Register of Controlled Trials) for studies comparing the diagnostic accuracy of PCE with endoscopic evaluation, intestinal ultrasound or magnetic resonance enterography (MRE). Data were analyzed by calculating forest plots and the use of the I2 statistic for heterogeneity. RESULTS: Fourteen studies were identified, with seven studies evaluating PCE diagnostic yield in Crohn's disease (CD) and seven studies in ulcerative colitis (UC). In CD, there was a trend to superiority of PCE over MRE and colonoscopy with a pooled odds ratio (OR) of 1.25 (95% CI, 0.85-1.86%) for the detection of CD. This translates to an increased diagnostic yield of 5% and 7% for PCE compared with MRE and colonoscopy, respectively. PCEs had a diagnostic sensitivity for the detection of UC of 93.8% (95% CI, 87.6-97.0%) and a specificity of 69.8% (95% CI, 38.2-89.6%). CONCLUSION: PCEs have a comparable diagnostic yield to colonoscopy and MRE in Crohn's disease. The major difficulty remains standardization of PCE scoring systems and the lack of transmural assessment. In UC, PCE has an excellent diagnostic sensitivity and positive predictive value, but there are limitations to its use including the lack of histologic assessment and poor specificity.

Tryptophan Metabolism 'Hub' Gene Expression Associates with Increased Inflammation and Severe Disease Outcomes in COVID-19 Infection and Inflammatory Bowel Disease.

The epithelial barrier's primary role is to protect against entry of foreign and pathogenic elements. Both COVID-19 and Inflammatory Bowel Disease (IBD) show commonalities in symptoms and treatment with sensitization of the epithelial barrier inviting an immune response. In this study we use a multi-omics strategy to identify a common signature of immune disease that may be able to predict for more severe patient outcomes. Global proteomic approaches were applied to transcriptome and proteome. Further semi- and relative- quantitative targeted mass spectrometry methods were developed to substantiate the proteomic and metabolomics changes in nasal swabs from healthy, COVID-19 (24 h and 3 weeks post infection); serums from Crohn's disease patients (scored for epithelial leak), terminal ileum tissue biopsies (patient matched inflamed and non-inflamed regions, and controls). We found that the tryptophan/kynurenine metabolism pathway is a 'hub' regulator of canonical and non-canonical transcription, macrophage release of cytokines and significant changes in the immune and metabolic status with increasing severity and disease course. Significantly modified pathways include stress response regulator EIF2 signaling (p = 1 × 10-3); energy metabolism, KYNU (p = 4 × 10-4), WARS (p = 1 × 10-7); inflammation, and IDO activity (p = 1 × 10-6). Heightened levels of PARP1, WARS and KYNU are predictive at the acute stage of infection for resilience, while in contrast, levels remained high and are predictive of persistent and more severe outcomes in COVID disease. Generation of a targeted marker profile showed these changes in immune disease underlay resolution of epithelial barrier function and have the potential to define disease trajectory and more severe patient outcomes.

Assisted Reproductive Technology in Crohn's Disease and Ulcerative Colitis: A Systematic Review and Meta-Analysis.

INTRODUCTION: Infertility may occur in women with Crohn's disease (CD) and ulcerative colitis (UC), especially after surgery such as ileal pouch-anal anastomosis (IPAA). Assisted reproductive technology (ART) may be an option, but the safety and efficacy in this setting has been based on small cohorts to date. We performed a systematic review and meta-analysis to address this data gap. METHODS: A systematic review and random-effects meta-analysis was performed until May 2020. The primary outcomes were pregnancy and live birth rates per cycle of ART. RESULTS: Eleven studies met inclusion criteria for the systematic review and 4 for the meta-analysis. Compared with the general population, women with CD (with and without previous surgery) had no difference in pregnancy rates (odds ratio [OR] = 0.69, 95% confidence interval [CI]: 0.45-1.05) but had reduced live births (OR = 0.67, 95% CI: 0.53-0.85) per cycle of ART. ART live birth rates are not reduced in women with medically managed CD; however, they are 49%-71% lower after CD-related surgery. Women with UC had no difference in both pregnancy rates (OR = 0.99, 95% CI: 0.63-1.55) and live birth rates (OR = 0.88, 95% CI: 0.67-1.17); however, live birth rates were reduced after IPAA failure (hazard ratio = 0.36, 95% CI: 0.14-0.92). Two studies did not identify any significant safety signals. DISCUSSION: ART is safe and effective in patients with UC and medically managed CD, with pregnancy and live birth rates similar to that of the general population. However, within the limitations of the available literature, current data suggest that efficacy is reduced in women with CD-related surgery and IPAA failure. Greater gastroenterologist awareness of ART is needed to facilitate timely fertility therapy referral when indicated, particularly in CD.

High prevalence of Crohn disease and ulcerative colitis among older people in Sydney.

OBJECTIVES: To determine the age-standardised prevalence of inflammatory bowel disease (IBD) in a metropolitan area of Sydney, with a focus on its prevalence among older people. DESIGN, SETTING: Population-based epidemiological study of people with IBD in the City of Canada Bay, a local government area in the inner west of Sydney, during 1 March 2016 - 10 November 2016. PARTICIPANTS: Patients diagnosed with confirmed IBD according to the Copenhagen or revised Porto criteria. MAIN OUTCOME MEASURES: Crude prevalence of IBD, including Crohn disease and ulcerative colitis; age-standardised prevalence of IBD, based on the World Health Organization standard population; prevalence rates among people aged 65 years or more. RESULTS: The median age of 364 people with IBD was 47 years (IQR, 34-62 years); 185 were women (50.8%). The crude IBD prevalence rate was 414 cases (95% CI, 371-456 cases) per 100 000 population; the age-standardised rate was 348 cases (95% CI, 312-385 cases) per 100 000 population. The age-standardised rate for Crohn disease was 166 cases (95% CI, 141-192 cases) per 100 000 population; for ulcerative colitis, 148 cases (95% CI, 124-171 cases) per 100 000 population. The IBD prevalence rate in people aged 65 years or more was 612 cases (95% CI, 564-660 cases) per 100 000, and for those aged 85 years or more, 891 cases (95% CI, 833-949 cases) per 100 000; for people under 65, the rate was 380 cases (95% CI, 342-418 cases) per 100 000. CONCLUSIONS: We found that the prevalence of confirmed IBD in a metropolitan sample was highest among older people. Challenges for managing older patients with IBD include higher rates of comorbid conditions, polypharmacy, and cognitive decline, and the immunosuppressive nature of standard therapies for IBD.

Australian consensus statements for the regulation, production and use of faecal microbiota transplantation in clinical practice.

OBJECTIVE: Faecal microbiota transplantation (FMT) has proved to be an extremely effective treatment for recurrent Clostridioides difficile infection, and there is interest in its potential application in other gastrointestinal and systemic diseases. However, the recent death and episode of septicaemia following FMT highlights the need for further appraisal and guidelines on donor evaluation, production standards, treatment facilities and acceptable clinical indications. DESIGN: For these consensus statements, a 24-member multidisciplinary working group voted online and then convened in-person, using a modified Delphi approach to formulate and refine a series of recommendations based on best evidence and expert opinion. Invitations to participate were directed to Australian experts, with an international delegate assisting the development. The following issues regarding the use of FMT in clinical practice were addressed: donor selection and screening, clinical indications, requirements of FMT centres and future directions. Evidence was rated using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system. RESULTS: Consensus was reached on 27 statements to provide guidance on best practice in FMT. These include: (1) minimum standards for donor screening with recommended clinical selection criteria, blood and stool testing; (2) accepted routes of administration; (3) clinical indications; (4) minimum standards for FMT production and requirements for treatment facilities acknowledging distinction between single-site centres (eg, hospital-based) and stool banks; and (5) recommendations on future research and product development. CONCLUSIONS: These FMT consensus statements provide comprehensive recommendations around the production and use of FMT in clinical practice with relevance to clinicians, researchers and policy makers.

Specific Bacteria and Metabolites Associated With Response to Fecal Microbiota Transplantation in Patients With Ulcerative Colitis.

BACKGROUND & AIMS: Fecal microbiota transplantation (FMT) can induce remission in patients with ulcerative colitis (UC). In a randomized controlled trial of FMT in patients with active UC, we aimed to identify bacterial taxonomic and functional factors associated with response to therapy. METHODS: We performed a double-blind trial of 81 patients with active UC randomly assigned to groups that received an initial colonoscopic infusion and then intensive multidonor FMT or placebo enemas, 5 d/wk for 8 weeks. Patients in the FMT group received blended homogenized stool from 3-7 unrelated donors. Patients in the placebo group were eligible to receive open-label FMT after the double-blind study period. We collected 314 fecal samples from the patients at screening, every 4 weeks during treatment, and 8 weeks after the blinded or open-label FMT therapy. We also collected 160 large-bowel biopsy samples from the patients at study entry, at completion of 8 weeks of blinded therapy, and at the end of open-label FMT, if applicable. We analyzed 105 fecal samples from the 14 individual donors (n = 55), who in turn contributed to 21 multidonor batches (n = 50). Bacteria in colonic and fecal samples were analyzed by both 16S ribosomal RNA gene and transcript amplicon sequencing; 285 fecal samples were analyzed by shotgun metagenomics, and 60 fecal samples were analyzed for metabolome features. RESULTS: FMT increased microbial diversity and altered composition, based on analyses of colon and fecal samples collected before vs after FMT. Diversity was greater in fecal and colon samples collected before and after FMT treatment from patients who achieved remission compared with patients who did not. Patients in remission after FMT had enrichment of Eubacterium hallii and Roseburia inulivorans compared with patients who did not achieve remission after FMT and had increased levels of short-chain fatty acid biosynthesis and secondary bile acids. Patients who did not achieve remission had enrichment of Fusobacterium gonidiaformans, Sutterella wadsworthensis, and Escherichia species and increased levels of heme and lipopolysaccharide biosynthesis. Bacteroides in donor stool were associated with remission in patients receiving FMT, and Streptococcus species in donor stool was associated with no response to FMT. CONCLUSIONS: In an analysis of fecal and colonic mucosa samples from patients receiving FMT for active UC and stool samples from donors, we associated specific bacteria and metabolic pathways with induction of remission. These findings may be of value in the design of microbe-based therapies for UC. ClinicalTrials.gov, Number NCT01896635.

Emergent colectomy rates decreased while elective ileal pouch rates were stable over time: a nationwide inpatient sample study.

PURPOSE: Despite advances in biologic therapy, approximately 10-15% of ulcerative colitis (UC) patients require surgery. We aimed to (1) examine the rates of emergent colectomy and elective ileal pouch anal anastomosis (IPAA) over time among UC patients in the USA and (2) investigate disparities in surgery rates by patient demographics. METHODS: Data from the Nationwide Inpatient Sample (NIS) from 2000 to 2014 were analyzed. Inclusion criteria were admissions with a primary UC ICD-9-CM diagnosis code and age > 18. Emergent cases were defined as those admitted through the emergency room with an outcome ICD-9-CM code for subtotal colectomy. Elective IPAA cases were defined with an outcome ICD-9-CM code for IPAA, used as a surrogate measure of colectomy. Patient and hospital-level demographics were analyzed. Temporal trends of colectomy were analyzed utilizing joinpoint-regression analysis with calculation of annual percentage change (APC). RESULTS: A total of 470,708 admissions were included over the 14-year period. Emergent colectomy rate significantly declined (APC - 7.35%, p = 0.0002), while the rate of elective IPAA remained stable (APC - 0.21%, p = 0.8). Emergent colectomy rates declined similarly across all demographics, though not as marked among patients age 50 and older and Medicare patients. Elective IPAA rates were significantly lower among blacks and patients with public insurance. CONCLUSIONS: There has been a significant decline in emergent UC colectomy rates in the USA; however, the overall need for surgery appears unchanged given stable IPAA rates. This suggests a limited impact on overall surgery rates with a shift from emergent to elective procedures.

Multidonor intensive faecal microbiota transplantation for active ulcerative colitis: a randomised placebo-controlled trial.

BACKGROUND: The intestinal microbiota is implicated in the pathogenesis of ulcerative colitis. Faecal microbiota transplantation is a novel form of therapeutic microbial manipulation, but its efficacy in ulcerative colitis is uncertain. We aimed to establish the efficacy of intensive-dosing, multidonor, faecal microbiota transplantation in active ulcerative colitis. METHODS: We conducted a multicentre, double-blind, randomised, placebo-controlled trial at three hospitals in Australia. We randomly allocated patients with active ulcerative colitis (Mayo score 4-10) in a 1:1 ratio, using a pre-established randomisation list, to either faecal microbiota transplantation or placebo colonoscopic infusion, followed by enemas 5 days per week for 8 weeks. Patients, treating clinicians, and other study staff were unaware of the assigned treatment. Faecal microbiota transplantation enemas were each derived from between three and seven unrelated donors. The primary outcome was steroid-free clinical remission with endoscopic remission or response (Mayo score ≤2, all subscores ≤1, and ≥1 point reduction in endoscopy subscore) at week 8. Analysis was by modified intention-to-treat and included all patients receiving one study dose. We performed 16S rRNA stool analysis to assess associated microbial changes. This trial is registered with ClinicalTrials.gov, number NCT01896635. The trial has ended; this report presents the final analysis. FINDINGS: From November, 2013, to May, 2015, 85 patients were enrolled to our trial, of whom 42 were randomly assigned faecal microbiota transplantation and 43 were allocated placebo. One patient assigned faecal microbiota transplantation and three allocated placebo did not receive study treatment and were excluded from the analysis. The primary outcome was achieved in 11 (27%) of 41 patients allocated faecal microbiota transplantation versus three (8%) of 40 who were assigned placebo (risk ratio 3·6, 95% CI 1·1-11·9; p=0·021). Adverse events were reported by 32 (78%) of 41 patients allocated faecal microbiota transplantation and 33 (83%) of 40 who were assigned placebo; most were self-limiting gastrointestinal complaints, with no significant difference in number or type of adverse events between treatment groups. Serious adverse events occurred in two patients assigned faecal microbiota transplantation and in one allocated placebo. Microbial diversity increased with and persisted after faecal microbiota transplantation. Several bacterial taxa were associated with clinical outcome; in particular, the presence of Fusobacterium spp was associated with lack of remission. INTERPRETATION: Intensive-dosing, multidonor, faecal microbiota transplantation induces clinical remission and endoscopic improvement in active ulcerative colitis and is associated with distinct microbial changes that relate to outcome. Faecal microbiota transplantation is, thus, a promising new therapeutic option for ulcerative colitis. Future work should focus on precisely defining the optimum treatment intensity and the role of donor-recipient matching based on microbial profiles. FUNDING: Broad Medical Research Program, Gastroenterological Society of Australia, Mount Sinai (New York) SUCCESS fund, University of New South Wales.