Confocal laser endomicroscopy as predictive biomarker of clinical and endoscopic efficacy of vedolizumab in ulcerative colitis: The DETECT study.

AIMS: In patients with ulcerative colitis (UC), no biomarker is available to help the physician to choose the most suitable biotherapy. The primary objective of this pilot study was to assess the feasibility of identification of α4ß7- and TNF-expressing cells, to predict the response to vedolizumab using confocal laser endoscopy (CLE). METHODS: Patients with moderate-to-severe UC, naïve of biotherapy, received vedolizumab. Clinical evaluation was performed at each infusion. Endoscopic evaluation was performed before inclusion and at week 22. Fresh colonic biopsies were stained using FITC-labelled vedolizumab and Alexa fluor-labelled adalimumab and ex vivo dual-band CLE images were acquired. Blood samples were collected to measure trough concentrations of vedolizumab and to determine absolute counts of T and B cells subpopulations, NK cells and monocytes. RESULTS: Nineteen patients were enrolled in the study and received at least one dose of vedolizumab. Clinical remission and endoscopic improvement were observed in 58% of whom 5 patients (45%) had an endoscopic subscore of 0. In terms of clinical response and remission, endoscopic improvement and histologic response, FITC-conjugated vedolizumab staining tended to be higher in responder patients compared to non-responders at week 22. A threshold value of 6 positive FITC-vedolizumab staining areas detected by CLE seemed informative to discriminate the responders and non-responders. The results were similar in terms of clinical remission and endoscopic improvement with a sensitivity of 78% and a specificity of 85% (p = 0.05). Trough concentrations and blood immune cells were not associated with responses to vedolizumab. CONCLUSION: This pilot study demonstrate that dual-band CLE is feasible to detect α4ß7- and TNF-expressing cells. Positive α4ß7 staining seems to be associated with clinical and endoscopic remission in UC patients treated by anti-α4ß7-integrin, subject to validation by larger-scale studies. Clinical-trial.gov: NCT02878083.

The PERFUSE study: The experience of patients receiving Adalimumab biosimilar SB5.

BACKGROUND: SB5 is an EMA-approved adalimumab biosimilar, having demonstrated bioequivalence, equivalent efficacy, and similar safety and immunogenicity to the reference product. AIMS: Describe patient training and satisfaction using patient-reported outcome measures (PROMs) and assess their impact on 12-month persistence on SB5. METHODS: The observational PERFUSE study included 318 Crohn's disease (CD) patients and 88 ulcerative colitis (UC) patients in 27 sites across France between October 2018 and December 2020. PROMs were collected at 1-month post-baseline using an online questionnaire (ePRO) designed with patient associations. Treatment persistence was collected during routine visits (up to 15 months post-initiation). Results are presented by prior experience with subcutaneous biologics and training in proper use of the injection device. RESULTS: 57.1% (n = 145) and 44.1% (n = 67) of naïve and pre-treated patients, respectively, answered the ePRO. Naïve patients were offered training more often (86.9% vs 31.3% respectively, p < 0.05), with disparities between sites. All subgroups' satisfaction scores were high. 12-month persistence on SB5 was significantly higher for respondents than for non-respondents (68.0% [60.9; 74.1] vs 52.3% [44.5; 59.6]; p < 0.05) and in patients with a better perception of their illness (OR=1.02, [1.0; 1.05]; p < 0.05). CONCLUSIONS: Early patient questionnaires may be useful to identify patients at higher risk of treatment discontinuation.

Comparative Acceptability of Therapeutic Maintenance Regimens in Patients With Inflammatory Bowel Disease: Results From the Nationwide ACCEPT2 Study.

BACKGROUND: Owing to growing number of therapeutic options with similar efficacy and safety, we compared the acceptability of therapeutic maintenance regimens in inflammatory bowel disease (IBD). METHODS: From a nationwide study (24 public or private centers), IBD patients were consecutively included for 6 weeks. A dedicated questionnaire including acceptability numerical scales (ANS) ranging from 0 to 10 (highest acceptability) was administered to both patients and related physicians. RESULTS: Among 1850 included patients (65.9% with Crohn's disease), the ANS were 8.68 ± 2.52 for oral route (first choice in 65.8%), 7.67 ± 2.94 for subcutaneous injections (first choice in 21.4%), and 6.79 ± 3.31 for intravenous infusions (first choice in 12.8%; P < .001 for each comparison). In biologic-naïve patients (n = 315), the most accepted maintenance regimens were oral intake once (ANS = 8.8 ± 2.2) or twice (ANS = 6.9 ± 3.4) daily and subcutaneous injections every 12 or 8 weeks (ANS = 7.9 ± 3.0 and ANS = 7.2 ± 3.2, respectively). Among 342 patients with prior exposure to subcutaneous biologics, the preferred regimens were subcutaneous injections (≥2 week-intervals; ANS between 9.1 ± 2.3 and 8.1 ± 2.7) and oral intake once daily (ANS = 7.7 ± 3.2); although it was subcutaneous injections every 12 or 8 weeks (ANS = 8.4 ± 3.0 and ANS = 8.1 ± 3.0, respectively) and oral intake once daily (ANS = 7.6 ± 3.1) in case of prior exposure to intravenous biologics (n = 1181). The impact of usual therapeutic escalation or de-escalation was mild (effect size <0.5). From patients' acceptability perspective, superiority and noninferiority cutoff values should be 15% and 5%, respectively. CONCLUSIONS: Although oral intake is overall preferred, acceptability is highly impacted by the rhythm of administration and prior medication exposures. However, SC treatment with long intervals between 2 injections (≥8 weeks) and oral intake once daily seems to be the most accepted modalities.

Considering both the route of medication delivery and the interval between 2 administrations, we observed a strong impact of patients' experience regarding previous treatments. The most accepted maintenance regimens were subcutaneous injections with interval ≥8 weeks and oral intake.

Efficacy of ustekinumab, vedolizumab, or a second anti-TNF agent after the failure of a first anti-TNF agent in patients with Crohn's disease: a multicentre retrospective study.

BACKGROUND: No study has performed a face-to-face comparison of biologics after the failure of the first anti-TNF agent in patients with Crohn's disease (CD). The aim of the study was to compare the efficacy of biologics in this setting. METHODS: Patients with CD who were refractory to a first anti-TNF agent, and treated with ustekinumab (UST), vedolizumab (VDZ), or a second anti-TNF drug as a second-line biological agent at 10 French tertiary centres from 2013 to 2019 were retrospectively included in this study. RESULTS: Among the 203 patients included, 90 (44%) received UST, 42 (21%) received VDZ and 71 (35%) received a second anti-TNF agent. The first anti-TNF agent was discontinued due to a primary nonresponse in 42 (21%) patients. At weeks 14-24, the rates of steroid-free remission were similar between the UST, VDZ and second anti-TNF groups (29%, 38% and 44%, respectively, p = 0.15). With a mean follow-up of 118 weeks, drug survival was shorter for patients who received ustekinumab treatment (p = 0.001). In the case of trough level less than 5 µg/ml, patients treated with a second anti-TNF agent had a higher postinduction remission rate (p = 0.002), and drug survival (p = 0.0005). No other relevant factors were associated with treatment efficacy, including trough levels greater than 5 µg/ml. CONCLUSIONS: VDZ, UST and a second anti-TNF agent exhibit similar efficacy in the short term, as second-biological line treatment in patients with CD who are refractory to a first anti-TNF agent, but shorter drug maintenance is observed for patients treated with UST.

Patient-reported continuous clinical response to golimumab in adults with moderately to severely active ulcerative colitis: results from GO OBSERVE, a real-world European observational study.

BACKGROUND: In PURSUIT, golimumab (GLM) was efficacious in patients with moderate-to-severe ulcerative colitis (UC). We assessed whether remote monitoring of combined patient-reported Mayo stool frequency and rectal bleeding scores is an effective real-world outcome measure for assessing maintenance of GLM-induced clinical response. METHODS: This was a 54-week prospective, observational cohort study conducted at 43 European outpatient clinics in adults with moderate-to-severe UC who were biologic naïve or had received a maximum of one other biological therapy. Patients were treated according to European GLM UC label/local practice. Clinical response (based on partial or full Mayo score) was assessed at week 6, 10, or 14 of induction, depending on local practice. Investigators remotely monitored scores every 4 weeks. The primary endpoint was the proportion of induction responders in patient-reported continuous clinical response (pCCR) at week 54, defined as absence of UC flare based on combined patient-reported Mayo stool frequency and rectal bleeding scores every 4 weeks and full or partial Mayo score. A key secondary endpoint was the proportion of induction responders in clinical remission at week 54. RESULTS: Among 109 patients, 37 (34.0%) received at least two GLM induction doses and completed induction in clinical response (induction responders). At week 54, 15/37 (40.5%) induction responders were in pCCR, and 21/37 (56.8%) were in clinical remission. CONCLUSION: In daily clinical practice, regular remote monitoring of combined patient-reported Mayo stool frequency and rectal bleeding scores appears to be a meaningful real-world outcome measure for monitoring maintenance of GLM-induced clinical response in UC.

Multi-expert annotation of Crohn's disease images of the small bowel for automatic detection using a convolutional recurrent attention neural network.

Background and study aims Computer-aided diagnostic tools using deep neural networks are efficient for detection of lesions in endoscopy but require a huge number of images. The impact of the quality of annotation has not been tested yet. Here we describe a multi-expert annotated dataset of images extracted from capsules from Crohn's disease patients and the impact of the quality of annotations on the accuracy of a recurrent attention neural network. Methods Images of capsule were annotated by a reader first and then reviewed by three experts in inflammatory bowel disease. Concordance analysis between experts was evaluated by Fleiss' kappa and all the discordant images were, again, read by all the endoscopists to obtain a consensus annotation. A recurrent attention neural network developed for the study was tested before and after the consensus annotation. Available neural networks (ResNet and VGGNet) were also tested under the same conditions. Results The final dataset included 3498 images with 2124 non-pathological (60.7 %), 1360 pathological (38.9 %), and 14 (0.4 %) inconclusive. Agreement of the experts was good for distinguishing pathological and non-pathological images with a kappa of 0.79 ( P  < 0.0001). The accuracy of our classifier and the available neural networks increased after the consensus annotation with a precision of 93.7 %, sensitivity of 93 %, and specificity of 95 %. Conclusions The accuracy of the neural network increased with improved annotations, suggesting that the number of images needed for the development of these systems could be diminished using a well-designed dataset.

VALIDation of the IBD-Disk Instrument for Assessing Disability in Inflammatory Bowel Diseases in a French Cohort: The VALIDate Study.

BACKGROUND AND AIMS: Inflammatory bowel diseases [IBD] are disabling disorders. The IBD-Disability Index [IBD-DI] was developed for quantifying disability in IBD patients but is difficult to use. The IBD-Disk is a visual adaptation of the IBD-DI. It has not been validated yet. The main objectives were to validate the IBD-Disk and to assess the clinical factors associated with a change in the score and its variability over time. METHODS: From May 2018 to July 2019, IBD patients from three university-affiliated hospitals responded twice to both IBD-Disk and IBD-DI at 3-12 month intervals. Validation included concurrent validity, reproducibility, and internal consistency. Mean IBD-Disk scores were compared according to clinical factors. Variability was assessed by comparing scores between baseline and follow-up visits. RESULTS: A total of 447 patients [71% Crohn's disease, 28% ulcerative colitis] were included in the analysis at baseline and 265 at follow-up. There was a good correlation between IBD-Disk and IBD-DI [r = 0.75, p <0.001]. Reproducibility was excellent [intra-class correlation coefficient = 0.90], as well as internal consistency [Cronbach's α = 0.89]. The IBD-Disk was not influenced by IBD type but was associated with female gender and physician global assessment. Extra-intestinal manifestations, history of resection, elevated C-reactive protein and faecal calprotectin also tended to be associated with higher disability. The IBD-Disk score decreased in patients becoming inactive over time. CONCLUSIONS: This study validated the IBD-Disk in a large cohort of IBD patients, demonstrating that it is a valid and reliable tool for quantifying disability for both CD and UC.

Efficacy and Safety of Tumor Necrosis Factor Antagonists in Treatment of Internal Fistulizing Crohn's Disease.

BACKGROUND & AIMS: Few data are available on the effects of tumor necrosis factor (TNF) antagonist therapy for patients with internal fistulizing Crohn's disease (CD) and there is debate regarding the risk of abscess. We aimed to assess the long-term efficacy and safety of anti-TNF therapy for patients with internal fistulas. METHODS: We performed a retrospective study of data collected from the Groupe d'Etude Thérapeutique des Affections Inflammatoires Digestives trial, from January 1, 2000, through December 31, 2017. Our final analysis included 156 patients who began treatment with an anti-TNF agent for CD with internal fistula (83 men; median disease duration, 4.9 y). The primary end point was the onset of a major abdominal surgery. Secondary analysis included disappearance of the fistula tract during follow-up evaluation and safety. The Kaplan-Meier method was used for statistical analysis. RESULTS: After a median follow-up period of 3.5 years, 68 patients (43.6%) underwent a major abdominal surgery. The cumulative probabilities for being surgery-free were 83%, 64%, and 51% at 1, 3, and 5 years, respectively. A concentration of C-reactive protein >18 mg/L, an albumin concentration <36 g/L, the presence of an abscess at the fistula diagnosis, and the presence of a stricture were associated independently with the need for surgery. The cumulative probabilities of fistula healing, based on imaging analyses, were 15.4%, 32.3%, and 43.9% at 1, 3, and 5 years, respectively. Thirty-two patients (20.5%) developed an intestinal abscess and 4 patients died from malignancies (3 intestinal adenocarcinomas). One patient died from septic shock 3 months after initiation of anti-TNF therapy. CONCLUSIONS: In a retrospective analysis of data from a large clinical trial, we found that anti-TNF therapy delays or prevents surgery for almost half of patients with CD and luminal fistulas. However, anti-TNF therapy might increase the risk for sepsis-related death or gastrointestinal malignancies.

Tumor cells hijack enteric glia to activate colon cancer stem cells and stimulate tumorigenesis.

BACKGROUND: Colon cancer stem cells (CSCs), considered responsible for tumor initiation and cancer relapse, are constantly exposed to regulatory cues emanating from neighboring cells present in the tumor microenvironment. Among these cells are enteric glial cells (EGCs) that are potent regulators of the epithelium functions in a healthy intestine. However, whether EGCs impact CSC-driven tumorigenesis remains unknown. METHODS: Impact of human EGC primary cultures or a non-transformed EGC line on CSCs isolated from human primary colon adenocarcinomas or colon cancer cell lines with different p53, MMR system and stemness status was determined using murine xenograft models and 3D co-culture systems. Supernatants of patient-matched human primary colon adenocarcinomas and non-adjacent healthy mucosa were used to mimic tumor versus healthy mucosa secretomes and compare their effects on EGCs. FINDINGS: Our data show that EGCs stimulate CSC expansion and ability to give rise to tumors via paracrine signaling. Importantly, only EGCs that were pre-activated by tumor epithelial cell-derived soluble factors increased CSC tumorigenicity. Pharmacological inhibition of PGE2 biosynthesis in EGCs or IL-1 knockdown in tumor epithelial cells prevented EGC acquisition of a pro-tumorigenic phenotype. Inhibition of PGE2 receptor EP4 and EGFR in CSCs inhibited the effects of tumor-activated EGCs. INTERPRETATION: Altogether, our results show that EGCs, once activated by the tumor, acquire a pro-tumorigenic phenotype and stimulate CSC-driven tumorigenesis via a PGE2/EP4/EGFR-dependent pathway. FUNDING: This work was supported by grants from the French National Cancer Institute, La Ligue contre le Cancer, the 'Région des Pays de la Loire' and the UNC Lineberger Comprehensive Cancer Center.

Proactive Therapeutic Drug Monitoring of TNF Antagonists in Inflammatory Bowel Disease.

BACKGROUND: Proactive therapeutic drug monitoring (TDM) to titrate tumor necrosis factor (TNF) antagonists has emerged recently as a tool to routinely monitor drug concentration to achieve target levels in patients with quiescent inflammatory bowel disease (IBD). METHODS: The purpose of the present review article was to present available data exploring the concept of proactive TDM. RESULTS: While several observational studies have identified an association between proactive TDM and better IBD outcomes, 2 randomized controlled studies did not confirm this advantage. CONCLUSIONS: Based on the evidence to date, proactive TDM cannot be recommended in daily practice. However, analysis is hampered by the low level of evidence for the cutoffs used and the need for point-of-care assays. Regarding economic issues and de-escalating strategies, proactive TDM may have several future indications in IBD. Exploratory studies on proactive TDM with newly available biologic agents in IBD are also awaited.

Inflammatory bowel disease: towards a personalized medicine.

The management of inflammatory bowel disease (IBD) has been transformed over the last two decades by the arrival of tumor necrosis factor (TNF) antagonist agents. Recently, alternative drugs have been approved, directed at leukocyte-trafficking molecules (vedolizumab) or other inflammatory cytokines (ustekinumab). New therapeutics are currently being developed in IBD and represent promising targets as they involve other mechanisms of action (JAK molecules, Smad 7 antisense oligonucleotide etc.). Beyond TNF antagonist agents, these alternative drugs are needed for early-stage treatment of patients with aggressive IBD or when the disease is resistant to conventional therapy. Personalized medicine involves the determination of patients with a high risk of progression and complications, and better characterization of patients who may respond preferentially to specific therapies. Indeed, more and more studies aim to identify factors predictive of drug response (corresponding to a specific signaling pathway) that could better manage treatment for patients with IBD. Once treatment has started, disease monitoring is essential and remote patient care could in some circumstances be an attractive option. Telemedicine improves medical adherence and quality of life, and has a positive impact on health outcomes of patients with IBD. This review discusses the current application of personalized medicine to the management of patients with IBD and the advantages and limits of telemedicine in IBD.

Comparative Acceptability and Perceived Clinical Utility of Monitoring Tools: A Nationwide Survey of Patients with Inflammatory Bowel Disease.

BACKGROUND: Objective control of intestinal inflammation during inflammatory bowel disease (IBD) is becoming the main driver for medical treatment. However, the monitoring tools-related burden remains poorly investigated. We aimed to evaluate their comparative acceptability and utility according to patients with IBD. METHODS: After a preliminary phase, the final questionnaire encompassing self-administered and physician questionnaires was prospectively and consecutively submitted to 916 patients with IBD from 20 public and private centers. Acceptability and utility visual analog scales (VAS) were expressed as median with interquartile range. RESULTS: Regarding the group of patients with Crohn's disease (n = 618), venipuncture (VAS = 9.3 [8.8-9.7]) and ultrasonography (VAS = 9.3 [8.7-9.7]) were the most acceptable tools (P < 0.0001, for each comparison), whereas rectosigmoidoscopy was the least acceptable tool (VAS = 4.4 [1.2-7.3]) (P < 0.0001, for each comparison). Wireless capsule endoscopy (VAS = 8.5 [5.2-9.3]), magnetic resonance enterocolonography (VAS = 8.0 [5.0-9.2]), and stools collection (VAS = 7.7 [4.6-9.3]) were more acceptable than colonoscopy (VAS = 6.7 [4.3-8.9]) (P < 0.0001, for each comparison). The acceptability was assessed in 298 patients with ulcerative colitis for venipuncture (VAS = 9.4 [8.8-9.7]), stools collection (VAS = 8.1 [5.7-9.4]), colonoscopy (VAS = 7.5 [4.7-9.2]), and rectosigmoidoscopy (VAS = 6.7 [2.8-9.1]); (P < 0.001 for each comparison). All monitoring tools were considered as highly useful by patients with IBD. Decreased acceptability was related to embarrassment for the collection/transport of stools (60.7%), bowel cleansing (76.3%) for colonoscopy, abdominal discomfort (51.3%) and rectal enema (36.6%) for rectosigmoidoscopy, bowel distension (48.3%) for magnetic resonance enterocolonography, and potential capsule retention (21.4%) for wireless capsule endoscopy. CONCLUSIONS: Among the IBD monitoring tools, endoscopy demonstrated the lowest acceptability supporting the development of alternative modalities. Patients' information and examination conditions should be improved to ensure proper monitoring adherence.

Golimumab for the treatment of ulcerative colitis.

INTRODUCTION: Tumor necrosis factor antagonists have revolutionized the therapeutic management of inflammatory bowel disease. Infliximab and adalimumab were the first biological agents used to induce and maintain remission in ulcerative colitis. More recently, a third tumor necrosis factor antagonist, golimumab, was approved, extending the therapeutic approach for moderate-to-severe ulcerative colitis. Areas covered: In this review, the authors review the literature on the efficacy and safety of golimumab in the context of other anti-TNF agents used in the treatment of this disease. The role of therapeutic drug monitoring in the case of loss of response to an anti-TNF agent is also discussed. Expert opinion: Golimumab is currently effective to induce and maintain remission in patients with ulcerative colitis, especially those patients who are naive for an anti-TNF agent. No large studies have evaluated the efficacy of golimumab after failure of a first-line TNF antagonist therapy. In the case of loss of response to a first anti-TNF agent, therapeutic drug monitoring is essential to determine the most suitable therapeutic option.

Advances in the Development of Janus Kinase Inhibitors in Inflammatory Bowel Disease: Future Prospects.

Inflammatory bowel disease (IBD) is caused by a dysregulation of the immune system, inducing the production of proinflammatory cytokines and adhesion molecules. A better understanding of the mucosal immune response in IBD has led to the development of new drugs directed at inflammatory cytokines and leukocyte-trafficking molecules. Beyond tumor necrosis factor antagonists and anti-integrin molecules, which act by blocking the interaction between gut-specific lymphocytes and their receptor on vascular endothelium, the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway represents a new target in IBD. JAK inhibitors are small molecules able to selectively target the activity of specific JAKs that play a role in signal transmission via interleukins. This review presents an overview of the role of the JAK/STAT signaling pathway and updated information for JAK molecules, which are promising drugs in IBD. Currently developed to treat ulcerative colitis and Crohn's disease, tofacitinib (in a phase III study) and filgotinib (in a phase II study), respectively, are the JAK inhibitors in the most advanced stage of development for IBD. However, the utility of, and adverse events associated with, these new drugs remain to be determined and clarified (in particular, the risk of herpes zoster infections), depending on the efficacy and tolerance determined from definitive studies. The availability of these drugs could enhance the therapeutic approach to IBD in the coming years, and reinforce the concept of personalized medicine for IBD patients.

Negative Screening Does Not Rule Out the Risk of Tuberculosis in Patients with Inflammatory Bowel Disease Undergoing Anti-TNF Treatment: A Descriptive Study on the GETAID Cohort.

AIM: to describe the characteristics of incident cases of tuberculosis [TB] despite negative TB screening tests, in patients with inflammatory bowel disease [IBD] undergoing anti-TNF treatment, and to identify the risk factors involved. METHODS: A retrospective descriptive study was conducted at GETAID centers on all IBD patients undergoing anti-TNF treatment who developed TB even though their initial screening test results were negative. The following data were collected using a standardized anonymous questionnaire: IBD, and TB characteristics and evolution, initial screening methods and results, and time before anti-TNF treatment was restarted. RESULTS: A total of 44 IBD patients [including 23 men; median age 37 years] were identified at 20 French and Swiss centers at which TB screening was performed [before starting anti-TNF treatment] based on Tuberculin Skin Tests [n = 25], Interferon Gamma Release Assays [n = 12], or both [n = 7]. The median interval from the start of anti-TNF treatment to TB diagnosis was 14.5 months (interquartile range [IQR] 25-75: 4.9-43.3). Pulmonary TB involvement was observed in 25 [57%] patients, and 40 [91%] had at least one extrapulmonary location. One TB patient died as the result of cardiac tamponade. Mycobacterium tuberculosis exposure was thought to be a possible cause of TB in 14 cases [32%]: 7 patients [including 6 health care workers] were exposed to occupational risks, and 7 had travelled to endemic countries. Biotherapy was restarted on 27 patients after a median period of 11.2 months [IQR 25-75: 4.4-15.2] after TB diagnosis without any recurrence of the infection. CONCLUSION: Tuberculosis can occur in IBD patients undergoing anti-TNF treatment, even if their initial screening results were negative. In the present population, TB was mostly extrapulmonary and disseminated. TB screening tests should be repeated on people exposed to occupational risks and/or travelers to endemic countries. Restarting anti-TNF treatment seems to be safe.

Could therapeutic drug monitoring of anti-TNF-α be useful to consider a de-escalation of treatment?

In recent years, many retrospective studies have demonstrated the interest of therapeutic anti-TNF drug monitoring in inflammatory bowel disease. This could be especially helpful in two different situations: a secondary loss of anti-TNF response where a re-elevation of drug levels by treatment optimization is predictive of better clinical outcome; a therapeutic de-escalation or discontinuation for Crohn's disease patients in long-standing remission where an undetectable anti-TNF drug level could be predictive of clinical remission.

Alterations in the intestinal microbiome (dysbiosis) as a predictor of relapse after infliximab withdrawal in Crohn's disease.

BACKGROUND: Crohn's disease (CD)-associated dysbiosis could predispose patients to relapse. Gut microbiota composition of patients from the prospective cohort study designed to identify predictive factors of clinical relapse after infliximab discontinuation (STORI Study) was investigated to determine the impact of dysbiosis in CD relapse. METHODS: Fecal samples from 33 patients with CD in this cohort were collected at baseline, 2 months, 6 months, and at the end of the follow-up period (19 relapsers and 14 nonrelapsers). Healthy volunteers subjects (n = 29) were used as a control group. The fecal microbiota composition was assessed using quantitative PCR, and comparisons between the patient groups were made at different time points using the Wilcoxon test. The analysis of the time-to-relapse was performed according to the baseline median level of each bacterial signal. RESULTS: Dysbiosis was observed in patients with CD compared with healthy subjects, and it was characterized by low mean counts of Firmicutes (Clostridium coccoides [P = 0.0003], C. leptum [P < 0.0001], and Faecalibacterium prausnitzii [P = 0.003]). Lower rates of Firmicutes were seen in relapsers compared with nonrelapsers. Moreover, a low rate of F. prausnitzii (P = 0.014) and a low rate of Bacteroides (P = 0.030) predicted relapse independently from high C reactive protein level (P = 0.0001). CONCLUSIONS: In this work, we report that CD-associated dysbiosis, characterized by a decrease in Firmicutes, correlates with the time-to-relapse after infliximab withdrawal. A deficit in some bacterial groups or species, such as F. prausnitzii, may represent a predictive factor for relapse. Restoring normobiosis in CD could be a new goal for optimal CD management.