Hart, Ailsa

Abstract Inflammatory bowel diseases (IBD), principally Crohn’s disease (CD) and ulcerative colitis (UC), are common chronic disorders involving inflammation and often progressive tissue damage. Genome-wide association studies have mapped many risk signals, but the causal variants, effector genes and relevant cellular contexts remain difficult to resolve, limiting mechanistic interpretation and therapeutic translation. Here we performed a multi-ancestry GWAS meta-analysis of 125,992 individuals with IBD and more than 1.2 million controls, identifying 619 independent association signals (374 novel) at 420 IBD regions that account for 77–80% of SNP-based heritability. Fine-mapping resolved 81 high-confidence variants, 41 not previously reported. Although most signals were shared between CD and UC, 39% showed IBD subtype specificity, with UC signals showing stronger enrichment in functional annotations from intestinal epithelial, secretory and enteroendocrine cells, and CD showing stronger genetic correlations with circulating inflammatory biomarkers, including C-reactive protein and glycoprotein acetylation. Latent causal modelling supported a causal effect of decreased high-density lipoprotein on CD risk. By integrating bulk and single-cell eQTL and pQTL resources using colocalisation and Mendelian randomisation, together with coding-variant evidence from exome sequencing, we prioritised 664 candidate effector genes across 341 signals, including 390 newly implicated IBD genes, revealing new biological mechanisms and candidate therapeutic targets supported by human genetics.

Abstract Inflammatory bowel disease (IBD) is a chronic immune-mediated disorder of the gastrointestinal tract whose genetic basis is only partly resolved because most risk variants identified by genome-wide association studies (GWAS) lie in non-coding regions, limiting direct gene assignment and biological interpretation 1,2 . Here we analysed whole-exome and whole-genome sequencing data from 86,213 IBD cases and 478,363 controls of European ancestry. We identified 68 IBD genes directly implicated by conditionally independent protein-coding associations across the allele frequency spectrum. Many newly implicated IBD genes are supported by orthogonal genomic or pleiotropic evidence, pointing to disease-related pathways and nominating targets with therapeutic relevance. We further identified allelic series and non-additive effects at key loci such as NOD2 and TYK2. These results show that large-scale sequencing can resolve disease genes and pathways that remain ambiguous from non-coding association alone, providing a more direct route from human genetics to biological insight and therapeutic hypotheses.

Abstract Background Icotrokinra is the first targeted oral peptide that selectively blocks the IL-23 receptor (IL-23R) and precisely inhibits the IL-23 pathway. In ANTHEM-UC—a Phase 2b, randomised, double-blind, placebo (PBO)-controlled, dose-ranging study in adults with moderately to severely active ulcerative colitis (UC)—all doses of icotrokinra achieved the primary endpoint of clinical response and delivered clinically meaningful improvements across key secondary endpoints at Week (W)12,1 which were maintained or improved at W28.2 Here we report the impact of icotrokinra on systemic and tissue biomarkers of inflammatory burden in UC. Methods Participants were randomised (1:1:1:1) to receive once-daily icotrokinra 100 mg, 200 mg, 400 mg, or PBO. Clinical inflammatory biomarkers, C-reactive protein (CRP) and faecal calprotectin (FCP), along with serum IL-23 pathway biomarkers (IL-22, IL-17A, and IL-17F) were used to determine the impact of icotrokinra on systemic inflammation. Gene expression changes in colonic biopsies were used to confirm tissue IL-23 pathway engagement and dampening of tissue inflammation with icotrokinra. Results At the W12 primary timepoint, all doses of icotrokinra attenuated levels of serum CRP and FCP (Figure 1). All doses of icotrokinra, but not PBO, markedly reduced serum levels of IL-22, IL-17A, and IL-17F at W12 relative to baseline. Greater reductions in these serum biomarkers of IL-23 pathway activation were observed with the 200 mg and 400 mg doses relative to the 100 mg dose (Figure 1, nominal p < 0.05). All doses of icotrokinra, but not PBO, markedly reduced expression of gene sets associated with the IL-23–driven inflammation in tissue at W12 relative to baseline (Figure 2, nominal p < 0.0001). With icotrokinra treatment, the tissue transcriptome more closely resembled that of healthy individuals, with decreased expression of gene sets associated with UC-relevant inflammatory cell types and increased expression of genes characteristic of healthy epithelial cells. Importantly, dampening of systemic and tissue inflammation with icotrokinra was sustained at W28 (Figures 1 & 2). Conclusion We show for the first time that blocking the IL-23R can inhibit IL-23-mediated inflammatory signaling in UC patients. Icotrokinra treatment induced a sustained (W28) reduction in systemic and tissue biomarkers of inflammatory burden in UC. Furthermore, icotrokinra induced transcriptional changes that are consistent with dampening of IL-23–driven inflammation and normalization of the tissue transcriptome. While all once-daily doses of icotrokinra attenuated systemic and tissue inflammation, greater reduction of systemic inflammatory burden was observed with the 200 mg and 400 mg doses of icotrokinra. References: 1. Abreu MT, et al. United European Gastroenterol J. 2025 10;13(suppl 8):172-3. 2. Jairath V, et al. Am J Gastroenterol. 2025 120;10(suppl 2):S312. Conflict of interest: Louis, Edouard: Education and Research Grants for my department: Abbvie, Takeda, Janssen, Pfizer, Fresenius-Kabi, Celltrion, EG pharma, Sandoz, Falk Personal Fees for conferences, advisory boards and consultancy: Abbvie, Takeda, Ferring, Pfizer, Janssen, Lilly, Galapagos, Celltrion, Arena, BMS, Falk, Biokuris, Fresenius-Kabi, Thabor Jairath, Vipul: Consulting fees from AbbVie, Alimentiv, Amgen, Anaptys Bio, Asahi Kasei, Asieris, Astra Zeneca, Attovia, Blackbird Labs, Bristol Myers Squibb, Boehringer Ingleheim, Biomebank, Caldera, Calluna, Catalytic Health, Celltrion, Ensho, Enthera, Exeliome Biosciences, Ferring, Fresenius Kabi, Gilead, Granite Bio, GSK, Johnson & Johnson, Lilly, Merck, Mountainfield, MRM Health, Nxera, Organon, OSE Immunotherapeutics, Pendopharm, Pioneering Medicine, Pfizer, Prometheus, Roche/Genentech, Sanofi, SCOPE, Shattuck Labs, Sorriso, Spyre, Synedgen, Takeda, Teva, Tillotts, Union Therapeutics, Ventus, Ventyx, Vividion, Xencor, Zealand Pharma. Siegmund, Britta: Consultant for AbbVie, Abivax, Boehringer Ingelheim, Bristol Myers Squibb, Dr. Falk Pharma, Eli Lilly, Endpoint Health, Galapagos, Johnson & Johnson, Materia Prima, MSD, Pfizer, Takeda, Wedbush Securities speaker for AbbVie, AlfaSigma, Bristol Myers Squibb, CED Service GmbH, Dr. Falk Pharma, Eli Lilly, Ferring, Galapagos, Johnson & Johnson, MD Education, MSD, Pfizer, Tr1xBio grant from Pfizer. Kannan, Arun K: Employee and shareholder of Johnson & Johnson Zeeman, Martha: Employee and shareholder of Johnson & Johnson Hart, Amy: Employee and shareholder of Johnson & Johnson Strawn, David: Employee and shareholder of Johnson & Johnson Venkat, Swati: Employee and shareholder of Johnson & Johnson Tomsho, Lynn: Employee and shareholder of Johnson & Johnson Mcrae, Bradford: Employee and shareholder of Johnson & Johnson Ruane, Darren: Employee and shareholder of Johnson & Johnson Surace, Lindsey: Employee and shareholder of Johnson & Johnson Erondu, Ngozi: Employee and shareholder of Johnson & Johnson Zhan, Joyce: Employee and shareholder of Johnson & Johnson Chen, Minhu: I have received speaker honoraria from Takeda China, Xian Janssen, and AbbVie China, as well as research funding from Takeda (China). Chachu, Karen: Advisory board for Johnson & Johnson consultant for OptumRx Matsuoka, Katsuyoshi: Grant: Abbvie Inc., Mochida Pharmaceutical Co., Ltd., ZERIA Pharmaceutical Co., Ltd., Nippon Kayaku Co., Ltd., JIMRO Co., Ltd. Personal Fees: Mitsubishi Tanabe Pharma, Janssen Pharmaceutical K.K., Abbvie Inc., EA Pharma Co., Ltd., Takeda Pharmaceutical Co., Ltd., Mochida Pharmaceutical Co., Ltd., ZERIA Pharmaceutical Co., Ltd., Nippon Kayaku Co., Ltd., Pfizer Inc., Kyorin Pharmaceutical Co., Ltd., Eli Lilly Japan K.K., Kissei Pharmaceutical Co., Ltd., Gilead Sciences, Celltrion Healthcare, Bristol-Myers Squibb Limdi, Jimmy: Speaker/consultancy fees from AbbVie, Abivax, Arena, BioHit, Bristol Myers Squibb, Celltrion, Eli Lilly, Ferring, Galapagos, Johnson & Johnson, MSD, Pfizer, Takeda research support from Galapagos, Takeda Rydzewska, Grazyna: Speaker and consultant fees from AbbVie, AlfaSigma, AstraZeneca, Bayer, Biocodex, Bristol Myers Squibb, Ferring, Johnson & Johnson, Lilly, PRO.MED.Pl, Recordati, Sanprobi, SOBI, Takeda travel/accommodation meeting expenses from AbbVie, Ferring, Takeda Abreu, Maria Teresa: Grant/Research Support: Janssen, Prometheus Bioscience, Takeda Consultant: Janssen, Prometheus Bioscience, Takeda Gilead, Eli Lilly, AbbVie Inc., Bristol Myers, Imedex, Loftus Jr, Edward V: Consultant/advisory board member for AbbVie, Amgen, Bristol Myers Squibb, Eli Lilly and Company, Genentech, Gilead Sciences, Johnson & Johnson, Pfizer, Takeda, UCB.

Abstract Background and Aims Intestinal ultrasound (IUS) is increasingly used to monitor treatment efficacy in inflammatory bowel disease (IBD) trials. However, standardized definitions for response, remission, and optimal assessment timing remain undefined. An international expert consensus meeting was held to establish IUS endpoints for clinical trials. Methods A panel of 35 international gastroenterologists and radiologists participated in a modified Delphi process, reviewing the literature and developing consensus statements. Agreement was defined as at least 75% consensus. Results Consensus was reached on 150 statements across four domains: general IBD (30 statements), luminal Crohn’s disease (CD) (43), perianal CD (51), and ulcerative colitis (UC) (26). For luminal CD and UC, ultrasound response was defined by: (1) a ≥25% reduction in bowel wall thickness (BWT) from baseline, or (2) multifactorial improvement, combining BWT reduction with ≥1 grade decrease in color Doppler signal (CDS) or another IUS parameter. Assessments were set at weeks 4-8 for the colon and week 12 for the terminal ileum. Ultrasound remission in luminal CD was defined as: (1) BWT normalization (≤3 mm) or (2) normalization of multiple parameters, including BWT, CDS, and all other IUS parameters. Similar remission criteria were proposed for UC, but the sigmoid BWT normal range (3-4 mm) remained uncertain. The bowel ultrasound score (BUSS) for CD and the Milan ultrasound criteria (MUC) for UC were supported as standardized scoring systems for trials. Conclusion This consensus provides standardized IUS definitions to enhance consistency in IBD trials, supporting the integration of IUS in future research.

Abstract Background and Aims Over 10% of patients with Crohn’s disease require permanent ileostomy. We aimed to summarize the existing data on diagnosis, definitions of recurrence, and management of Crohn’s disease patients with permanent ileostomy. Methods MEDLINE, Embase, and CENTRAL databases were searched from inception to February 6, 2024. Randomized controlled trials, cohort and cross-sectional studies, and case series of more than 5 patients reporting on postoperative recurrence or the need for surgery in patients with Crohn’s disease and permanent ileostomy were included. Search results were independently screened, and full text of all titles meeting eligibility criteria was obtained. Outcomes of interest included diagnostic techniques, recurrence definitions, and management approaches. We estimated pooled rates (with 95% confidence interval [CI]) of recurrence. Results Thirty cohort studies including 2055 Crohn’s patients with permanent ileostomy were included (53% female, median age at the time of ileostomy creation 32 years, the most common reason for ileostomy was refractory disease). The postoperative recurrence rate was 27% (95% CI, 21.3–33.3, 26 studies, 451/1805 patients). Modalities for diagnosis of Crohn’s disease recurrence were symptoms (15 studies), endoscopy (4 studies), histology from endoscopic biopsies (2 studies), imaging (5 studies), and surgery (22 studies). The reported definitions of recurrence for each modality were heterogeneous. Conclusions There is a lack of standardized monitoring tools and criteria for diagnosing recurrence in patients with Crohn’s disease and permanent ileostomy. The results of this systematic review will form the basis of a global expert recommendation exercise focused on developing management standards and trial endpoints for this condition.

AbstractBackgroundPYRAMID was an international post‐marketing registry that aimed to collect data on the long‐term safety and effectiveness of adalimumab treatment per local standard of care in patients with moderately to severely active Crohn's disease (CD). Here, we present post hoc analyses of observational data from patients who became pregnant while participating in this registry and receiving adalimumab.MethodsFrom the subpopulation of patients receiving adalimumab who became pregnant while taking part in PYRAMID, data on patient characteristics, pregnancy outcomes, and complications of pregnancy were analysed retrospectively.ResultsAcross the PYRAMID registry, 293 pregnancies occurred in patients who had gestational adalimumab exposure (average disease duration at last menstrual period: 8.6 years), resulting in 300 pregnancy outcomes. A total of 197 pregnancies (67.2%) were exposed to adalimumab in all trimesters per physician's decision. Of the known reported outcomes (96.3%), 81.7% (236/289) were live births, 10.4% (30/289) were spontaneous abortions, 4.8% (14/289) elective terminations, 2.8% (8/289) ectopic pregnancies, and 0.3% (1/289) was a stillbirth. Congenital malformations (pulmonary valve stenosis and tricuspid valve incompetence) were reported in one infant. In addition to the pregnancy outcomes described above, 23 complications of pregnancy were reported in 20 patients.ConclusionsThis analysis showed that adalimumab treatment in patients with CD, who became pregnant whilst participating in the PYRAMID registry, contributed no additional adverse effects during the pregnancy course or on pregnancy outcomes.

SummaryBackgroundTofacitinib is an oral, small molecule Janus kinase inhibitor for the treatment of ulcerative colitis. We present final data from OCTAVE Open, an open‐label, long‐term extension study.AimsThe primary objective of OCTAVE Open was to assess the safety and tolerability of long‐term tofacitinib in patients with ulcerative colitis; evaluating efficacy was a secondary objective.MethodsEligible patients included OCTAVE Induction 1&2 non‐responders and OCTAVE Sustain completers/treatment failures. Patients in remission at OCTAVE Open baseline received tofacitinib 5 mg b.d.; all others received 10 mg b.d. Incidence rates (unique patients with events/100 patient‐years) for adverse events of special interest were calculated; ≤7.0 years of observation. Efficacy endpoints derived from Mayo score were reported ≤36 months (last scheduled endoscopy visit).ResultsIn OCTAVE Open, 769 of 944 patients (81.5%) initially received tofacitinib 10 mg b.d. Among all patients (2440.8 patient‐years of exposure), incidence rates (IRs; 95% confidence intervals) for deaths and adverse events of special interest were: deaths, 0.25 (0.09‐0.54); serious infections, 1.61 (1.14‐2.20); herpes zoster (non‐serious and serious), 3.16 (2.47‐3.97); opportunistic infections, 0.87 (0.54‐1.33); major adverse cardiovascular events, 0.16 (0.04‐0.42); malignancies (excluding non‐melanoma skin cancer), 1.03 (0.67‐1.52); non‐melanoma skin cancer, 0.75 (0.45‐1.19); deep vein thrombosis, 0.04 (0.00‐0.23); pulmonary embolism, 0.21 (0.07‐0.48). At Month 36, 66.9% and 40.3% showed clinical response, 64.6% and 37.1% had endoscopic improvement, and 58.9% and 33.7% maintained or achieved remission, with tofacitinib 5 and 10 mg b.d. respectively.ConclusionTofacitinib demonstrated consistent safety up to 7.0 years. Data collected up to Month 36 support long‐term efficacy beyond the 52‐week maintenance study.