Introduction

In corticosteroid-resistant acute severe ulcerative colitis (ASUC), second-line treatment involves infliximab or cyclosporine (CYCLO). With increasing antiTNFα exposed patients, CYCLO is often chosen to prevent emergency colectomy but is limited to the induction phase due to tolerability, serving as a bridge until effective maintenance therapy. In this setting, limited data on vedolizumab (VDZ) and ustekinumab (UST) as maintenance make the choice of an optimal bridge strategy challenging. This study aimed to compare the efficacy of VDZ and UST after CYCLO induction in corticosteroid-resistant ASUC.

Aims & Methods

This single-center retrospective cohort included all patients hospitalized for ASUC, responding to CYCLO induction, and starting VDZ or UST maintenance. ASUC was defined by modified Truelove and Witts criteria, with response to CYCLO defined by a Lichtiger score reduction to <10 points for 2 consecutive days, with a minimum 3-point decrease by day 7. The primary outcome was colectomy-free survival; secondary outcomes were treatment persistence and safety.

Results

From 2014-2024, 62 ASUC patients received CYCLO. Eighteen were excluded (non-response, tofacitinib [n=7], infliximab [n=3], and/or emergency colectomy [n=14]), leaving 44 CYCLO-responsive ASUC patients (median age 39, IQR 30-58, 60% female), with 35 on VDZ (79%) and 9 on UST (21%). ASUC was related to ulcerative colitis in 84% (73% pancolitis) and undetermined or Crohn's colitis in 16%. Disease duration was 7 years (IQR 2-15), with 91% prior biologic exposure, primarily antiTNF. Presentation included Lichtiger score 10 (IQR 10-12), CRP 46 mg/L (22-79), albumin 29 g/L (27-30), fecal calprotectin 778 µg/g (450-1650), UCEIS 7 (5-8), and Mayo endoscopic score 3 (3-3). Colectomy-free survival at 2 years was 79% with VDZ and 47% with UST (p=0.03). Treatment persistence at 2 years was 43% with VDZ, and 47% with UST (p=0.47). After adjusting for maintenance therapy, disease type, and severity, colectomy risk factors included hypoalbuminemia (HR=1.2; 95%CI:1.02-1.4, p=0.018) and prior tofacitinib exposure (HR=9.1; 95%CI:1.5-55.6, p=0.017). Over a median 37-month follow-up (95%CI:35-40), 34% of patients experienced adverse events, with 19% severe (mainly CYCLO-related), including 2 deep vein thromboses in the VDZ group and 1 infection in the UST group. No deaths occurred.

Conclusion

Our study suggests that VDZ may provide higher colectomy-free survival at 2 years than UST in CYCLO-responsive ASUC, with comparable treatment persistence. Hypoalbuminemia and prior tofacitinib exposure were identified as independent risk factors for colectomy, emphasizing the role of patient profiling in treatment selection. Further prospective studies are needed to refine bridge strategies in ASUC.

Introduction

Epithelial injury is a hallmark of chronic mucosal damage in Crohn’s disease (CD), which can lead to fibrostenotic strictures. Type VII collagen, a critical component of the epithelial basement membrane, forms U-shaped anchoring fibrils that link the basement membrane to the interstitial matrix by binding fibrillar collagen. Genetic mutations in the COL7A1 gene, which encodes type VII collagen, are known to impair fibril formation and reduce tissue tensile strength, resulting in epithelial dysfunction, as seen in disorders such as dystrophic epidermolysis bullosa. This highlights the essential structural role of type VII collagen in maintaining matrix stability. In CD, the importance of this protein is underscored by the presence of autoantibodies targeting type VII collagen in up to 50% of patients with CD. Loss of tissue integrity, because of loss of the interaction between the basement and interstitial matrix, leads to tissue dysfunction and fibrosis.

Aims & Methods

We investigated C7M, a biomarker of type VII collagen degradation, to assess its specificity for intestinal mucosal damage. We analyzed serum samples from CD patients enrolled in a prospective cohort study. The cohort included 62 CD patients undergoing surgical resection for fibrostenotic strictures and 49 patients with luminal disease receiving treatment adjustments without surgery. Serum was collected at baseline, post-operative day 1 (POD1), and one-month post-resection. C7M levels were quantified using a competitive ELISA.

Results

At baseline, C7M levels were significantly elevated in fibrostenotic CD patients (median: 9.79ng/mL) compared to those with luminal CD patients (median: 6.03ng/mL) (p<0.01, AUC: 0.69). In the resected group, C7M levels rose sharply on POD1 (p<0.0001, AUC: 0.81), suggesting acute release in response to surgical injury. By one-month post-surgery, C7M levels had returned to baseline, closely resembling those observed in luminal CD patients (p<0.0001, AUC: 0.80). C7M also demonstrated mild-moderate correlations to biochemical markers of inflammation, including CRP (rho=0.62, p<0.0001), hemoglobin (rho=-0.28, p=0.0024), thrombocytes (rho=0.24, p=0.0105), albumin (rho=-0.52, p<0.0001), and fecal calprotectin (rho=0.25, p=0.019).

Conclusion

C7M was elevated in fibrostenotic CD patients relative to luminal CD, indicating its potential as a biomarker of more severe or complex mucosal pathology. The pronounced but transient increase following surgery, with normalization within one month, further supports C7M as a dynamic marker of intestinal epithelial damage. These findings suggest C7M may serve as a novel, disease-specific biomarker for assessing mucosal integrity and inflammatory burden in CD.

Disclosure

Full time employee at Nordic Bioscience

Introduction

Artificial intelligence tools for endoscopic assessment of Ulcerative Colitis remain limited due to suboptimal agreement with expert readers and reliance on small, inconsistently labeled datasets. We developed a novel computer vision model (DovaVision) trained on a large-scale, expert-annotated video dataset to assess UC activity using detailed frame-level features.

Aims & Methods

DovaVision was pre-trained using DINOv2 self-supervised learning on 845 colonoscopies and millions of GI images, then significantly refined using annotations collected via a proprietary platform. 15 IBD central readers (CRs) scored video frames for five UC features (vascular pattern, bleeding, ulcers/erosions, friability, erythema) across multiple severity levels. Annotators underwent standardized onboarding to ensure high inter-rater reliability. The model comprises two vision transformer architectures: a Quality Control (QC) module to exclude low-quality/non-diagnostic frames, and a Scoring module that outputs feature-specific severity grades. Model outputs include burned-in heatmaps (for mapping of disease activity to specific timepoints) and structured JavaScript Object Notation (JSON) files.

Results

A total of 83.8 million frames from 200 colonoscopy videos were labeled by 3 expert CRs across 7 categories per video, yielding 16.9 million merged labels by majority vote. Inter-rater agreement on modified Mayo Endoscopic Score (MES) showed strong reliability (ICC = 0.86; QWK = 0.88). On a 31-video validation set from 3 separate data sources, DovaVision showed equivalency with the gold standard of CR consensus (2+1 majority vote), achieving a QWK of 0.904 and ICC of 0.907. In comparison, the pool of 3x CRs assigned/video on this same set showed ICC of 0.905. On friability assessment—a challenging feature-- DovaVision showed 90% agreement and 0.811 ICC when compared to gold standard (3x CR majority vote), while the agreement for 3 CRs per video was only 0.447 ICC on the same set. The average model inference time was short at 3.5 minutes per video. The model also outputs continuous “frame-by-frame” level information on the sub-score characteristics. The model is an entire data processing pipeline deployed on a cloud architecture with an API for secure authentication, bulk data upload, and secure results storage/retrieval.

Conclusion

DovaVision is a validated AI-based model for automated grading of UC severity on endoscopy. Its high concordance with expert readers, detailed feature-level (sub-score characteristics) analysis, and rapid inference support real-world integration into clinical and research workflows. Although further validation with additional datasets is required.

Disclosure

Dr. Michael Byrne is the Chairman, Founder and CMO at Dova Health Intelligence

Introduction

Tyrosine kinase 2 (TYK2) inhibitors block signaling downstream of multiple pro-inflammatory cytokines involved in immune-mediated inflammatory diseases, including inflammatory bowel disease, and may have an improved safety profile relative to Janus kinase inhibitors. Phase 2 studies of the highly selective and potent TYK2 inhibitor zasocitinib in Crohn’s disease (CD; NCT06233461) and ulcerative colitis (UC; NCT06254950) are ongoing.^1,2 Here, we describe the design of a combined open-label extension trial (NCT06764615), which will include patients from both parent trials who are responsive to treatment.

Aims & Methods

Patients are eligible for the phase 2 parent studies in CD and UC if they are aged 18–75 years with moderately to severely active disease, and have inadequate or loss of response to, or intolerance of, ≥ 1 standard or advanced therapy. Patients who have failed treatment with ≥ 3 classes of advanced therapy are excluded. Patients are randomized to one of three (CD) or two (UC) doses of zasocitinib, or placebo, for a 12-week double-blind induction phase followed by a 40-week sponsor-open (CD) or open-label (UC) maintenance period. At the end of the parent trials, patients will be eligible for the combined open-label extension if they are clinical (CD) or symptomatic (UC) responders at Week 52, defined as: (1) CD: a ≥ 30% decrease in average daily very soft or liquid stools and/or a ≥ 30% decrease in average daily abdominal pain from baseline; and (2) UC: a ≥ 1-point and ≥ 30% decrease from baseline in partial modified Mayo score, and a ≥ 1-point decrease from baseline in rectal bleeding (RB) subscore or achievement of an absolute RB subscore of ≤ 1. All enrolled patients will receive the same dose of open-label, oral, once-daily zasocitinib for a maximum of 108 weeks, with study visits every 12 weeks, followed by a 4-week safety follow-up period. Data analysis will be descriptive, with no formal statistical comparisons performed.

Results

The primary objective of the study is to determine long-term safety and tolerability, assessed through the incidence of treatment-emergent adverse events or adverse events of special interest. Secondary endpoints will assess the long-term efficacy of zasocitinib, including clinical, symptomatic, or endoscopic response or remission by visit or at Weeks 48 and 108, according to indication, and effects on patient-reported outcomes, including fatigue, bowel urgency, abdominal pain, and disease-specific health-related quality of life.

Conclusion

This open-label extension trial will provide data on the long-term safety of zasocitinib, as well as durability of treatment response among patients with CD or UC who experience treatment benefit in the phase 2 parent studies.

References

1. Jairath V et al. UEG Journal 2024;12(S8):1033.
2. Peyrin-Biroulet L et al. UEG Journal 2024;12(S8):1041.

Disclosure

GP reports receiving personal payments, honoraria, or speaker fees from AbbVie, Allergan, BMS, Celltrion, Ferring, Galapagos, Janssen, Pfizer, Sorriso, Takeda, and Tillotts, travel grants or fellowships from AbbVie, Celltrion, Ferring, Janssen, Takeda, and Tillotts, and is a Director and shareholder in Ampersand Health. SGR, LZ, VAN, LA, FN, TF, LS, and NS are employees and shareholders of Takeda.

Introduction

Janus kinase inhibitors (JAKi) exhibit distinct performance characteristics versus monoclonal antibody (mABs) biological agents in the management of ulcerative colitis (UC). There is a lack of direct comparative effectiveness data of JAKi small molecules versus mABs in the real world.

Aims & Methods

In the absence of direct head-to-head comparisons, we determined the persistence of tofacitinib (TOF) versus vedolizumab and tumour necrosis factor inhibitor (TNFi) mABs in advanced therapy (AT)-naïve and AT-exposed real-world UC subjects from a population-based prospective registry.

The Persistence Australian National IBD Cohort (PANIC5) registry collected AT prescribing data for the entire Australian population up until Dec 2021. In Australia, all advanced therapies for IBD are prescribed without a hierarchical order in subjects with moderate-severe UC refractory to conventional therapies, irrespective of occupation and insurance status. Treatment is provided indefinitely in those that enter into clinical remission. Non-persistence was defined as failure to continue AT prescriptions for >6-months. Propensity score matching (PSM) statistically controlled for baseline selection biases. Kaplan-Meier survival curves were generated for AT persistence and compared using the log-rank test. Cox proportional hazards regression models were employed to calculate hazard ratios (HR) and 95% confidence intervals (CI). P<0.05 was deemed statistically significant (SPSS, USA).

Results

A total of 9,671 consecutive UC patients were recruited (53% male, 23,348 patient-years of follow up). The cohort comprised 14,772 treatment lines: 6,044 infliximab (IFX), 1,981 adalimumab (ADA), 5,467 vedolizumab (VED), 750 golimumab (GOL) and 530 tofacitinib (TOF). TOF exhibited superior persistence versus IFX (HR: 1.88, 95%CI: 1.34-2.63, P<0.001), ADA (HR: 2.10, 95%CI: 1.49-2.94, P<0.001) and GOL (HR: 2.20, 95%CI: 1.55-3.11, P<0.001) but not versus VED (HR: 1.28, 95%CI: 0.92-1.80, P=0.14). Following PSM, TOF was not significantly higher in persistence compared to mABs among AT-naïve subjects (all P>0.05). However, TOF showed superior persistence compared to all mABs among AT-exposed (all P<0.001). The persistence of TOF (P=0.77) did not significantly decline moving from AT-naive- to AT-exposed treatment status, unlike for TNFi (-8 months) and VED (-19 months, both P<0.001). PSM-multivariate Cox regression showed predictors of higher persistence to be use of TOF, AT-naïve status, use of immunomodulator. Rankings of persistence of ATs are presented for AT-naïve- and AT-exposed UC subjects (Table).

Conclusion

This is the first real-world study comparing treatment effectiveness using a national universal insurance persistence dataset. It found that tofacitinib had significantly greater persistence than biological agents in patients with ulcerative colitis who had previously received advanced therapy. Unlike monoclonal antibodies, tofacitinib did not show a decline in persistence after exposure to advanced therapy. Given these findings, JAK inhibitors like tofacitinib should be strongly considered for patients switching advanced therapies in ulcerative colitis.

Disclosure

RL advisory board: AbbVie, Aspen, BMS, Celgene, Celltrion, Chiesi, Ferring, Glutagen, Hospira, Janssen, Lilly, MSD, Novartis, Pfizer, Prometheus Biosciences, Takeda; research grants: Joanna Tiddy USYD, McCusker Charitable Foundation, Celltrion, Shire, Janssen, Takeda, Gastroenterological Society of Australia, NHMRC, Gutsy Group, Pfizer, MRFF