Introduction

Immune checkpoint inhibitors (ICIs) have marked a breakthrough in the management of a wide range of cancer types, leading to increased overall survival. However, this treatment is frequently associated with the onset of various immune-related adverse events (irAEs), including ICI-related diarrhea and colitis.¹ Current recommendations for patients with diarrhea or colitis grade 2 or higher (graded via CTCAE)² include the discontinuation of ICI and administration of immune suppressants (e.g. steroids or biologics), which may lead to worse outcomes in these patients.³ Therefore, alternative therapeutic strategies to manage irAEs are needed. The gut microbiota plays a pivotal role in the onset of gastrointestinal irAEs, but the role of its therapeutic modulation on these disorders is mostly unknown. ^4,5

Aims & Methods

Our aim was to evaluate the efficacy and safety of therapeutic microbiome modulation for gastrointestinal irAEs in cancer patients. We enrolled cancer patients affected by ICI-related diarrhea/colitis referred to our Microbiome Clinic from January 2023 to March 2025. After clinical evaluation, patients were stratified according to severity of diarrhea (graded via CTCAE)² and then received a microbiome-modulating therapy. Patients were followed-up for at least 8 week after the initiation of therapy. We collected data about patient demographics (age and gender), patient’s overall health status as assessed by the the Charlson Comorbidity Index (CCI)⁶, type of cancer, oncological therapy and its suspension, time in weeks from initiation of cancer therapy to onset of diarrhea, severity of diarrhea (graded via CTCAE)², time in weeks until resolution of diarrhea and resumption of oncological therapy

Results

We enrolled 42 patients in the study period (8 males, 34 females, mean age 58,3 years-old, mean CCI-index 5.8). All patients were treated with ICI (Pembrolizumab: n=25 , Dostarlimab: n=4, Nivolumab: n=4; Atezolizumab: n=3; Novulumab and Ipilumab: n=2, Cemiplimab: n=2; Mogamulizumab: n=1; Pertuzumab: n=1). Ten patients experienced G1 diarrhea (23,8%), 16 (38,1) G2, 15 (35,7%) G3 and one G4 (2,4%). As indicated by current European Guidelines³, 30 patients (71,4%) had to interrupt ICI due to diarrhea. Multi-strain probiotics were administered to 27 (64.3% ) patients, rifaximin to 22 (52,4%). Overall, 21 patients (50%) needed therapy with systemic steroids. Seven patients who experienced ICI-related colitis refractory to steroids and biologics were successfully treated with FMT. Twenty-eight patients (66.7% ) had a resolution of the diarrhea (G0) and 11 patients (26.2%) had diarrhea G1 at a mean time of 8 weeks. Upon resolution of diarrhea, nine of the 30 patients who had interrupted ICI (30%) were able to resume the treatment. None of the patients experienced any adverse event related to gut microbiota modulation as defined by CTCAE².

Conclusion

Therapeutic modulation of gut microbiota appears to be a promising safe and effective approach for treating ICI-related diarrhea and colitis. However, these preliminary findings need confirmation through more consolidated and well-designed studies.

References

1. Dougan M, Wang Y, Rubio-Tapia A, Lim JK. AGA Clinical Practice Update on Diagnosis and Management of Immune Checkpoint Inhibitor Colitis and Hepatitis: Expert Review. Gastroenterology. 2021;160(4):1384-1393. doi:10.1053/j.gastro.2020.08.063
2. Freites-Martinez A, Santana N, Arias-Santiago S, Viera A. Using the Common Terminology Criteria for Adverse Events (CTCAE - Version 5.0) to Evaluate the Severity of Adverse Events of Anticancer Therapies. Actas Dermosifiliogr. 2021;112(1):90-92. doi:10.1016/j.ad.2019.05.009
3. Haanen J, Obeid M, Spain L, et al. Management of toxicities from immunotherapy: ESMO Clinical Practice Guideline for diagnosis, treatment and follow-up. Ann Oncol. 2022;33(12):1217-1238. doi:10.1016/j.annonc.2022.10.001
4. Wang Y, Wiesnoski DH, Helmink BA, et al. Fecal microbiota transplantation for refractory immune checkpoint inhibitor-associated colitis. Nat Med. 2018;24(12):1804-1808. doi:10.1038/s41591-018-0238-9
5. Wang T, Zheng N, Luo Q, et al. Probiotics Lactobacillus reuteri Abrogates Immune Checkpoint Blockade-Associated Colitis by Inhibiting Group 3 Innate Lymphoid Cells. Front Immunol. 2019;10. doi:10.3389/fimmu.2019.01235
6. Charlson ME, Pompei P, Ales KL, MacKenzie CR. A new method of classifying prognostic comorbidity in longitudinal studies: Development and validation. J Chronic Dis. 1987;40(5):373-383. doi:10.1016/0021-9681(87)90171-8

Disclosure

G.I. has received personal fees for acting as speaker for Biocodex, Danone, Sofar, Malesci, Metagenics and Tillotts Pharma, and for acting as consultant and/or advisor for Ferring Therapeutics, Giuliani, Malesci and Tillotts Pharma. A.G. reports personal fees for consultancy from Eisai Srl, 3PSolutions, Real Time Meeting, Fondazione Istituto Danone, SinergieSrl, Board MRGE and Sanofi SpA personal fees for acting as a speaker for Takeda SpA, AbbVie and Sandoz SpA and personal fees for acting on advisory boards for VSL3 and Eisai. G.C. has received personal fees for acting as advisor for Ferring Therapeutics. All other authors have no conflicts of interest to disclose.

Introduction

Histological assessment in Inflammatory Bowel Disease (IBD) is often required with endoscopic diagnoses to establish disease activity. This is evident in patients where histological healing is a major therapeutic goal and when endoscopic healing can also exhibit microscopic disease. IBD can manifest in numerous landmark features which are structural and inflammatory related. Histological activity is determined through erosion/ulceration, architectural changes in tissue morphology, mucin depletion and presence of varied inflammatory cells the colonic crypts, Muscularis Mucosae (MM) and Lamina Propria (LP). Histological scoring systems vary in complexity and methodology and subject to discrepancies in inter-rater consensus. Our model aims to provide accurate measurements of key histological features in Ulcerative Colitis (UC) used in scoring systems as both a decision support tool for improving pathologist scoring alignment and sensitive quantitative metrics of inflammatory cells to evaluate disease activity.

Aims & Methods

We developed an ensemble of convolutional neural networks to identify cell types, tissue foreground, crypts, MM, and haemorrhage in H&E images of IBD biopsy data. Models were trained with expert-labelled annotations comprising 34,289 image-annotation pairs (80% training, 20% validation) from in-house and publicly available data. Model accuracy was assessed with 6,464 held-out image-annotation pairs from 26 Whole Slide Images (WSIs) from all sites of the large intestine commonly sampled during endoscopic investigation, while ground truth annotations were reviewed by GI-trained pathologists to certify accuracy. We used geospatial methods to derive boundaries of the LP from other predicted domains, associate cells to delineated regions, measure architectural changes and derive spatially differentiated metrics of inflammatory burden in 66 patients with confirmed UC.

Results

The AI model spatially differentiates and segments cell types and tissue compartments. This produces metrics for inflammatory cell counts in regions of interest such as crypts, LP, and MM. Goblet cell segmentation within crypts allows for measurement of mucin depletion. This can be visualized for pathologists where each inflammatory cell type across the WSI is represented as density metrics. Automated quantification of inflammatory cells across AI-identified tissue domains throughout the bowels of UC patients revealed large intra- and inter-patient variability.

Conclusion

Our AI model can measure histological healing by detecting architectural change, inflammatory cell number, goblet cell reduction and erosions and ulceration. This allows for metrics and visual overlays to assist with pathologist reading and quantifying changes in mucosal biopsies in a clinical trial setting which requires extremely sensitive tools only AI can provide.

Disclosure

DW/AM/RL/PA/PW and CL are employees at Perspectum Ltd. EF and RG are consultants for Perspectum Ltd. All other co-authors have no conflicts of interest to declare relevant to this work.

Introduction

Irritable bowel syndrome (IBS) is defined as a disorder of gut-brain interaction (DGBI) and is characterised by intestinal immune activation, increased intestinal permeability, and structural and functional brain alterations. DGBI patients have a higher prevalence of psychological comorbidities. Nevertheless, the exact pathophysiological link between these factors and the sequence of events is unknown. Gut alterations have been suggested to induce brain neuroinflammation in DGBI, but scientific evidence is lacking.

Aims & Methods

The present study aims to assess whether GI alteration induces brain neuroinflammation, alters brain function, and, consequently, induces psychological comorbidities. A unique longitudinal study was conducted from 30 to 220 days of age to establish the chronological sequence of intestinal and neurological changes. For this, we utilised the BioBreeding diabetes-prone (BBDP) rat model, which spontaneously develops intestinal inflammation, increased permeability, and colonic hypersensitivity^{1, 2}and has been employed as a model of DGBI. The BioBreeding diabetes-resistant (BBDR) was used as control. Anxiety-like behaviour was assessed using the elevated plus maze. Intestinal permeability was assessed in vivo by measuring the passage of 4 kDa and 70 kDa dextrans into the blood, thereby evaluating paracellular and transcellular permeability, respectively. The appearance of red colour, given by the mixture of the dextrans in the stools, was used to assess overall intestinal motility. The blood-brain barrier (BBB) integrity and brain metabolic profile were assessed using contrast-enhanced magnetic resonance imaging (0.25 mL/100g weight of 0.05 mM, gadolinium) and proton magnetic resonance spectroscopy, respectively.

Results

BBDP rats exhibit an increased colonic permeability starting from 90 days, and reduced GI motility at 90 and 160 days. Interestingly, this increased permeability is accompanied by an increased BBB permeability at 220 days only in the anterior cingulate cortex (ACC) but not in the hippocampus, insula, amygdala, or thalamus. BBDP rats showed a slight increase in total choline and myoinositol concentrations in the ACC and the insula at late time points, which may indicate increased neuroinflammation. BBDP rats also have higher concentrations of glutamine-glutamate in the insula and N-acetyl aspartate in the ACC. Moreover, BBDP rats develop anxiety-like behaviour at 160 and 220 days.

Conclusion

The BBDP rat model supports the current hypothesis that increased gut permeability can lead to brain neuroinflammation, altered function, and, consequently, to psychological comorbidities.
EU-funded DISCOvERIE project (No. 848228).

References

1. Meleine M, Accarie A, Wauters L, et al. Colonic hypersensitivity and low-grade inflammation in a spontaneous animal model for functional gastrointestinal disorders. Neurogastroenterol Motil 2019;31:e13614.
2. Vanuytsel T, Vanormelingen C, Vanheel H, et al. From intestinal permeability to dysmotility: the biobreeding rat as a model for functional gastrointestinal disorders. PLoS One 2014;9:e111132.

Introduction

Anti-tumor necrosis factor (TNF)-α are the first target therapies approved for the treatment of steroid-dependent or -refractory ulcerative colitis (UC). Drugs with different mechanisms of action have recently entered the market, but data on the optimal management of UC after failure of first-line anti-TNF-α are lacking.

Aims & Methods

The PODIUM study is a multicentre, retrospective, observational study that aims to compare the real-life effectiveness and safety of second-line vedolizumab (VDZ), ustekinumab (UST) and tofacitinib (TOF) in patients with UC. Consecutive patients with UC who had failed at least one anti-TNF-α and were never exposed to other target therapies were enrolled from 12 centres across Europe. Sociodemographic data, data on clinical activity and adverse events of interest (AEIs, defined as AE requiring temporary/permanent drug discontinuation or medical intervention) were retrospectively extracted from medical records, from the initiation of second-line therapy until one year of observation/drug discontinuation/last available follow-up. The primary outcome was the cumulative probability of achieving steroid-free clinical remission (SFCR), defined as stool frequency=0-1 and rectal bleeding=0 and no concomitant steroids, over the first year of treatment; inverse probability of treatment weighting (IPTW), calculated as the inverse of the probability of receiving each drug (IPTW=1/Propensity Score), was applied to the primary outcome to account for imbalances in cohorts’ characteristics. We performed an interim analysis including all data collected up to March 15^th 2024; data collection is still ongoing at the submission of this Abstract.

Results

Data on 303 patients (172 VDZ, 63 UST, 68 TOF) were included in the analysis. The main baseline characteristics are presented in Table 1. After IPTW, the cumulative probability of achieving SFCR during the first year was 51.0%, 59.1% and 64.1% for VDZ, UST and TOF, respectively; both UST and TOF were superior to VDZ at Log-rank test (p<0.001), with no differences between the two. At weighted logistic regression, female sex (adjusted Odds Ratio, aOR, 0.06, Confidence Interval, CI, 95% 0.41-0.73, p<0.001) and higher Charlosn Comorbidity Index calculated without considering age (aOR 0.73, 95% CI 95% 0.60-0.88, p=0.001) were independently associated with a lower probability of achieving SFCR during the first year. Recorded AEIs were 16 (4 infections) in the VDZ group (9.3% of VDZ-treated patients), 6 (1 infection) in the UST group (9.5% of UST-treated patients), and 15 (5 infections, including 1 Zoster reactivation) in the TOF group (22.1% of TOF-treated patients).
Table 1

Conclusion

This preliminary analysis suggests that both UST and TOF might have superior effectiveness, compared to VDZ, as second-line agents in patients with UC after anti-TNF-α. Confirmatory analysis with a larger sample size will be performed. A slightly higher rate of AEIs was observed in the TOF group.

Disclosure

Giuseppe Privitera received consultancy fees from Alphasigma and Janssen. Cristina Bezzio received lecture fees and served as a consultant for Takeda, MSD, Ferring, Abbvie, Galapagos and Janssen. Edoardo Vincenzo Savarino has served as speaker for Abbvie, Agave, AGPharma, Alfasigma, Aurora Pharma, CaDiGroup, Celltrion, Dr. Falk, EG Stada Group, Fenix Pharma, Fresenius Kabi, Galapagos, Janssen, JB Pharmaceuticals, Innovamedica/Adacyte, Malesci, MayolyBiohealth, Omega Pharma, Pfizer, Reckitt Benckiser, Sandoz, SILA, Sofar, Takeda, Tillots, and Unifarco; has served as a consultant for Abbvie, Agave, Alfasigma, Biogen, Bristol-Myers Squibb, Celltrion, DiademaFarmaceutici, Dr. Falk, Fenix Pharma, Fresenius Kabi, Janssen, JB Pharmaceuticals, Merck & Co, Nestlè, Reckitt Benckiser, Regeneron, Sanofi, SILA, Sofar, Synformulas GmbH, Takeda, and Unifarco; he has received research support from Pfizer, Reckitt Benckiser, SILA, Sofar, Unifarco, Zeta Farmaceutici. Daniela Pugliese received speaker fees and/or advisory board from AbbVie, Galapagos, MSD, Takeda and Janssen, Pfizer. Iago Rodriguez-Lago has received financial support for traveling and educational activities from or has served as an advisory board member for Abbvie, Adacyte, Celltrion, Chiesi, Danone, Ferring, Faes Farma, Janssen, Galapagos, MSD, Pfizer, Roche, Takeda, and Tillotts Pharma. Financial support for research: Tillotts Pharma. Manuel Barreiro-de Acosta has served as a speaker, consultant and advisory member for and has received research funding from MSD, AbbVie, Janssen, Kern Pharma, Celltrion, Takeda, Gilead, Celgene, Pfizer, Sandoz, Biogen, Fresenius, Ferring, Faes Farma, Dr. Falk Pharma, Chiesi, Gebro Pharma, Adacyte and Vifor Pharma. Sara Onali has received speaker fees from AbbVie, Takeda, Janssen, Amgen, Galapagos and Norgine. Massimo Claudio Fantini has received speaker and consultancy fees from AbbVie, Takeda, Janssen-Cilag, Pfizer, Sandoz, Biogen, Galapagos, Bristol-Myers Squibb, and MSD; and research grants from Pfizer and Janssen-Cilag. Karmiris K has served as speaker, consultant, and advisory member for Abbvie, Amgen, Enorasis, Ferring, Galenica, Genesis, Janssen, MSD, Pfizer, Takeda and Vianex. Henit Yanai has received consulting fees Abbvie, Ferring, Janssen, Neopharm Ltd., Pfizer, Takeda; Payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events Abbvie, Janssen, Pfizer, Takeda, Neopharm Ltd.; Participation on a Data Safety Monitoring Board or Advisory Board Abbvie, Neopharm Ltd., Pfizer, Takeda. Ana Gutierrez has served as speaker, consultant and advisory member for or has received research funding from MSD, Abbvie, Pfizer, Kern Pharma, Takeda, Janssen, Ferring, Faes Farma, Shire Pharmaceuticals, Tillotts Pharma, Chiesi and Otsuka Pharmaceutical. Luca Pastorelli has received consultant and/or speaker fees from Giuliani, Ferring, Janssen, Takeda. María Chaparro has served as a speaker and consultant for and has received research or education funding from MSD, AbbVie, Hospira, Pfizer, Takeda, Janssen, Ferring, Shire Pharmaceuticals, Dr. Falk Pharma, Tillotts Pharma, Biogen, Gilead and Lilly. Yamile Zabana has received speaker and/or consultant fees from AbbVie, Adacyte, Almirall, Amgen, Dr Falk Pharma, FAES Pharma, Ferring, Janssen, MSD, Otsuka, Pfizer, Shire, Takeda, Galapagos, Boehringer Ingelheim and Tillots. Alessandro Armuzzi: consulting and/or advisory board fees from AbbVie, Amgen, Biogen, Boehringer Ingelheim, Bristol-Myers Squibb, Celgene, Celltrion, Eli-Lilly, Ferring, Galapagos, Gilead, Janssen, MSD, Mylan, Pfizer, Protagonist Therapeutics, Roche, Samsung Bioepis, Sandoz, Takeda; lecture and/or speaker bureau fees from AbbVie, Amgen, Arena, Biogen, Bristol-Myers Squibb, Eli-Lilly, Ferring, Galapagos, Gilead, Janssen, MSD, Mitsubishi-Tanabe, Novartis, Pfizer, Roche, Sandoz, Samsung Bioepis, Takeda; and research grants from MSD, Pfizer, Takeda and Biogen. The remaining authors declare no competing interests. The remaining Authors declare no competing interests.

Introduction

Immune checkpoint inhibitors (ICIs), a new class of immunotherapeutic agents, are the first-line treatment for many advanced epithelial cancers. Gastrointestinal irAEs, particularly diarrhea and colitis, affect approximately 40% of ICI-treated patients and often lead to therapy discontinuation.¹ High-dose corticosteroids represent the first-line treatment, but about one-third of patients show inadequate response and require second-line immunosuppressants such as Infliximab or Vedolizumab.² As the body of evidence about the role of gut microbiota in the pathogenesis of GI irAE grows, fecal microbiota transplantation (FMT) is emerging as a potential treatment for steroid- and biologic-refractory ICI-induced colitis.³ Although data are still preliminary, FMT represents a promising therapeutic strategy in this setting.

Aims & Methods

The aim of this study is to evaluate the safety and efficacy of FMT in patients referred to our Microbiome clinic for steroid- and biologic-refractory ICI-induced colitis. After clinical evaluation, patients were treated with FMT via colonoscopy from healthy donors. FMT was performed as already described, following international clinical guidelines.^4,5 Following the endoscopic procedure, patients were evaluated at 1, 4, 8, and 12 weeks. We collected data on: patient characteristics, cancer type, cancer treatment and its suspension, severity of diarrhea before FMT (graded via CTCAE)⁶, time in weeks from initiation of cancer therapy to onset of diarrhea, grade of diarrhea following treatment and resumption of ICI.

Results

Our cohort included 7 patients with steroid- and biologic-refractory ICI-induced colitis (grade 1: n=0 ; grade 2: n=1 ; grade 3: 5=x; grade 4: n=1). Four patients were affected by renal cell carcinoma, 2 by melanoma, 1 by pulmonary cancer. All patients were treated with PD-1/PDL-1 inhibitors or CTLA-4 ( Nivolumab: n= 3; Nivolumab and Ipilimumab: n=2; Durvalumab: n= 1; Pembrolizumab: n= 1) and 6 patients interrupted ICI due to gastrointestinal irAEs. All patients received single FMT from healthy donors via colonoscopy. Following FMT, diarrhea improved to grade ≤ 1 in 6 patients (85%) at week 1, 4, 8, and 12 after the procedure, suggesting a sustained effect of microbiome modulation in the medium term. One patient died during follow-up for reasons other than ICI-colitis.

Conclusion

Our preliminary findings suggest that FMT may be a promising therapeutic strategy for refractory ICI-colitis. Further, larger and randomized studies are warranted to confirm our data.

References

1. Dougan M, Wang Y, Rubio-Tapia A, Lim JK. AGA Clinical Practice Update on Diagnosis and Management of Immune Checkpoint Inhibitor Colitis and Hepatitis: Expert Review. Gastroenterology. 2021;160(4):1384-1393. doi:10.1053/j.gastro.2020.08.063
2. Haanen J, Obeid M, Spain L, et al. Management of toxicities from immunotherapy: ESMO Clinical Practice Guideline for diagnosis, treatment and follow-up. Ann Oncol. 2022;33(12):1217-1238. doi:10.1016/j.annonc.2022.10.001
3. Wang Y, Wiesnoski DH, Helmink BA, et al. Fecal microbiota transplantation for refractory immune checkpoint inhibitor-associated colitis. Nat Med. 2018;24(12):1804-1808. doi:10.1038/s41591-018-0238-9
4. Cammarota G, Ianiro G, Kelly CR, et al. International consensus conference on stool banking for faecal microbiota transplantation in clinical practice. Gut. 2019;68(12):2111-2121. doi:10.1136/gutjnl-2019-319548
5. Ianiro G, Rossi E, Thomas AM, et al. Faecal microbiota transplantation for the treatment of diarrhoea induced by tyrosine-kinase inhibitors in patients with metastatic renal cell carcinoma. Nat Commun. 2020;11(1):4333. doi:10.1038/s41467-020-18127-y
6. Freites-Martinez A, Santana N, Arias-Santiago S, Viera A. Using the Common Terminology Criteria for Adverse Events (CTCAE - Version 5.0) to Evaluate the Severity of Adverse Events of Anticancer Therapies. Actas Dermosifiliogr. 2021;112(1):90-92. doi:10.1016/j.ad.2019.05.009

Disclosure

G.I. has received personal fees for acting as speaker for Biocodex, Danone, Sofar, Malesci, Metagenics and Tillotts Pharma, and for acting as consultant and/or advisor for Ferring Therapeutics, Giuliani, Malesci and Tillotts Pharma. A.G. reports personal fees for consultancy from Eisai Srl, 3PSolutions, Real Time Meeting, Fondazione Istituto Danone, SinergieSrl, Board MRGE and Sanofi SpA personal fees for acting as a speaker for Takeda SpA, AbbVie and Sandoz SpA and personal fees for acting on advisory boards for VSL3 and Eisai. G.C. has received personal fees for acting as advisor for Ferring Therapeutics. All other authors have no conflicts of interest to disclose.