Robert, Marie E.

ABSTRACT Background Coeliac disease is due to an acquired, lifelong gluten‐specific immune response resulting in a gluten‐dependent chronic immune‐mediated enteropathy associated with gastrointestinal and extraintestinal morbidity. Strictly avoiding dietary gluten is the only available management but has never been subjected to rigorous efficacy assessment now required for a pharmaceutical agent. Gluten‐free diet (GFD) is partially and inconsistently effective, but it places a high burden on patients, families, the food industry, and regulators and is defined inconsistently around the world, highlighting the need for effective and convenient adjunctive pharmacological therapies. Aims To summarize key patient, scientific, and regulatory considerations for coeliac disease drug development based on a multi‐stakeholder meeting focused on accelerating clinical trials. Methods A pre‐competitive meeting convened by the Beyond Celiac Coalition (May 2024) included patients with coeliac disease, academic experts, pharmaceutical industry representatives, and participants from the US Food and Drug Administration. Moderated panel addressed patient priorities, symptom and histologic endpoints, biopsy and histology methods, gluten challenge design, clinical trial duration, and regulatory expectations. Themes were synthesized qualitatively with focus on trial design implications and unresolved questions. Results Participants described high symptom burden and psychosocial impact despite gluten‐free diet adherence underscoring unmet therapeutic need in coeliac disease. Regulatory perspectives emphasized the need for clinically meaningful improvement and evidence of intestinal benefit, framed as symptom and histology co‐primary endpoints in clinical trials. These expectations were discussed as most applicable to trial populations with both clinically meaningful symptoms and active histologic injury at baseline; for other phenotypes, it was emphasized that endpoint strategy, the role of gluten exposure, and trial duration should be tailored case by case to the population and mechanism of action. Practical challenges identified included endpoint selection and definition, discordance between symptoms and histology, selecting fit‐for‐purpose symptom measures; standardizing biopsy acquisition and central histology reads to address patchiness and variability, pre‐specifying definitions of meaningful histologic change given ongoing uncertainty about healing, and trial feasibility. Controlled gluten exposure was discussed as a tool to improve interpretability of efficacy outcomes, with careful consideration of dose, duration, patient burden and safety. Discussion addressed the ideal length of the double‐blind period, including a shorter 24‐week double‐blind study with an open‐label extension versus a 52‐week double‐blind design. Trial duration should balance scientific rigour, patient retention, and the need for longer‐term safety and durability data, with flexibility to tailor the approach to context. Conclusions Progress in coeliac disease drug development will require patient‐centred, scientifically robust but feasible trial designs with appropriate endpoints, justified use of gluten exposure, consideration of improved biomarkers to reduce patient burden and early regulatory engagement. Continued multi‐stakeholder collaboration, including dedicated consideration of paediatric drug development, is essential to advance effective therapies.

Abstract Pancreatic ductal adenocarcinoma (PDAC) is a devastating cancer with an increasing incidence and extremely dismal prognosis. Discovery and mechanistic understanding of the genetic and epigenetic drivers of PDAC is therefore of critical importance. Here, we uncover serine protease inhibitor Kazal type 1 (SPINK1) as a putative determinant of clinical progression and demonstrate that it can have a non-canonical function as a regulator of epigenomic states of PDAC cells and associated extensive changes in gene expression. We show that SPINK1 expression, which varies in PDAC, is associated with key aggressive phenotypic cancer states and is correlated with the expression of stemness markers both in vitro and in patient samples. Mechanistically, our results strongly suggest that SPINK1 acts through a new signaling axis, by interacting with COL18A1 in the Golgi apparatus, promoting endostatin release and eventually inducing extensive histone H3 modifications. These results reveal a new function of SPINK1 in PDAC and suggest a potential therapeutic route to combat PDAC aggressiveness by targeting the SPINK1-COL18A1-endostatin signaling.

INTRODUCTION: Wide-area transepithelial sampling with 3-dimensional computer-assisted analysis (WATS 3D ) has been shown to increase the detection rate of dysplasia (and intestinal metaplasia) in patients with Barrett's esophagus (BE). The purpose of this study was to evaluate the interobserver variability and accuracy of diagnosing BE-associated dysplasia in WATS 3D specimens among gastrointestinal (GI) pathologists without prior experience with this technology. METHODS: Five GI pathologists underwent a 4-hour in-person (at microscope) and virtual training session and then evaluated digital images of discrete cellular foci from 60 WATS 3D cases with BE (20 nondysplastic BE [NDBE], 20 low-grade dysplasia [LGD], and 20 high-grade dysplasia/esophageal adenocarcinoma [HGD/EAC]). Each case consisted of 1 hematoxylin and eosin–stained image (cell block), and 1 liquid cytology or papanicolaou-stained smear image (120 images in total). RESULTS: The overall kappa value among the 5 study pathologists was excellent (overall kappa = 0.93; kappa = 0.93 and 0.97 for cell block and smear specimens, respectively). There were no significant differences noted in kappa values in interpretation of the cell block vs smear specimens or in any of the individual diagnostic categories when the latter were evaluated separately. Furthermore, agreement was perfect (100%) regarding detection of neoplasia (either LGD, HGD, or EAC). Diagnoses were made with complete confidence in 91% of instances. DISCUSSION: We conclude that GI pathologists, without any prior experience in interpretation of WATS 3D specimens, can undergo a short training session and then diagnose these specimens with a very high level of accuracy and reproducibility.

Validated nonbiopsy methods to assure duodenal mucosal healing in celiac disease are lacking, yet ongoing mucosal injury is associated with anemia, osteoporosis, and lymphoma. Most providers utilize clinical data as surrogates of mucosal status to avoid additional esophagogastroduodenoscopy. The reliability of such surrogates to predict mucosal recovery has been incompletely evaluated. The aim of this study was to rigorously assess patterns of histologic mucosal recovery at follow-up in celiac disease and to correlate findings with clinical data. Gastrointestinal pathologists from 13 centers evaluated initial and follow-up duodenal biopsies from 181 celiac disease patients. Marsh scores and intraepithelial lymphocytes (IELs)/100 enterocytes were assessed blindly. Histology at follow-up was correlated with symptoms, immunoglobulin A anti–tissue transglutaminase titers and gluten-free diet adherence. Fifty-six/181 (31%) patients had persistent villous blunting and 46/181 (25%) patients had just persistently elevated IELs at follow-up, with only 79/181 (44%) patients having complete histologic remission. IEL normalization (82/181; 45%) lagged villous recovery (125/181;69%). In a minority of patients, villous blunting was limited to proximal duodenal biopsies. No correlation was found between Marsh scores and symptoms, normalization of immunoglobulin A anti–tissue transglutaminase serology, or diet adherence. Children showed greater recovery of Marsh score (P<0.001) and IELs (P<0.01) than adults. Persistent mucosal injury is common in celiac disease, with discordant villous/IEL normalization. Pathologist awareness of expected findings in celiac disease follow-up biopsies, including their frequent lack of correlation with clinical data, is important for patient management, and has implications for eligibility criteria for therapeutics currently in development.

Objective Effective medical therapy and validated trial outcomes are lacking for small bowel Crohn’s disease (CD) strictures. Histopathology of surgically resected specimens is the gold standard for correlation with imaging techniques. However, no validated histopathological scoring systems are currently available for small bowel stricturing disease. We convened an expert panel to evaluate the appropriateness of histopathology scoring systems and items generated based on panel opinion. Design Modified RAND/University of California Los Angeles methodology was used to determine the appropriateness of 313 candidate items related to assessment of CD small bowel strictures. Results In this exercise, diagnosis of naïve and anastomotic strictures required increased bowel wall thickness, decreased luminal diameter or internal circumference, and fibrosis of the submucosa. Specific definitions for stricture features and technical sampling parameters were also identified. Histopathologically, a stricture was defined as increased thickness of all layers of the bowel wall, fibrosis of the submucosa and bowel wall, and muscularisation of the submucosa. Active mucosal inflammatory disease was defined as neutrophilic inflammation in the lamina propria and any crypt or intact surface epithelium, erosion, ulcer and fistula. Chronic mucosal inflammatory disease was defined as crypt architectural distortion and loss, pyloric gland metaplasia, Paneth cell hyperplasia, basal lymphoplasmacytosis, plasmacytosis and fibrosis, or prominent lymphoid aggregates at the mucosa/submucosa interface. None of the scoring systems used to assess CD strictures were considered appropriate for clinical trials. Conclusion Standardised assessment of gross pathology and histopathology of CD small bowel strictures will improve clinical trial efficiency and aid drug development.

Small intestinal biopsy interpretation has been the cornerstone for the diagnosis of celiac disease for over 50 years. Despite the existence of sensitive and specific serological tests, duodenal mucosal biopsies continue to be obtained in the vast majority of patients in whom a diagnosis of celiac disease is being considered. The accurate evaluation of these biopsies requires coordination and information sharing between the gastroenterologist, laboratory, and pathologist in order to optimize tissue sampling, preparation and interpretation. This document, a collaboration between the Rodger C. Haggitt Gastrointestinal Pathology Society and the North American Association for the Study of Celiac Disease, is intended to provide clinicians and pathologists with a summary of best practices in the use of endoscopy and biopsy for patients with suspected celiac disease. The authors present a comprehensive and critical appraisal of the literature with respect to the topics of endoscopic findings, best methods for the obtaining biopsies, completing the pathology form and pathologic assessment, including evaluating intraepithelial lymphocytes and villous architecture. A discussion of conditions with overlapping pathologic findings in duodenal mucosal biopsies is presented. In order to provide additional guidance for challenging situations, the authors include an appendix containing practical suggestions. This review may be utilized in interdisciplinary discussions to optimize care for patients with possible celiac disease.