Inflammatory bowel disease (IBD), like other disorders of the GI tract due to inflammation, has not established standardized disease activity criteria. This is found in both ulcerative colitis (UC) and Crohn’s disease (CD). Benjamin Click and his Target-IBD investigators showed that histologic risk revealed by findings of inflammation on index biopsy predicted in 513 evaluable U.S. patients predicted loss of response to medical management. These biopsy changes occurred at mean 11.8 months (IQR 5.3–20.1 months). However, no specific histologic scoring system was used (e.g., Nancy, Robarts, or Geboes) to put the findings in the context of many IBD clinical trials. These scoring methods were used by Verstockt and the group from Belgium, who used all of them to identify a one-year post-treatment outcome of refractory UC treated with tofacitinib. They found a median histologic remission rate of 3–3, 17–26.3, and 13–17, respectively, for the 40 patients studied. Patients had an endoscopic remission rate of one year of 32.5%. A correlation between histologic remission and endoscopic remission was found at year one (p=0.006).
Miguel Regueiro reinforced the clinical applications of markers in UC, including fecal calprotectin, C-reactive protein (CRP), and endoscopic/histologic healing, during his IBD theatre presentation on May 22.
Some new techniques for Crohn’s disease activity scoring included the use of ultrasound. De Cristofaro and the team from Rome presented a poster of distinction evaluating 100 patients. Their technique used small intestine contrast ultrasonography and compared this to clinical activity using the Harvey Bradshaw index (HBI), CRP, and fecal calprotectin. They found that different echo behaviors correlated with different CD behaviors, with a hypoechoic pattern, in particular, correlating well (p=0.0017) with a greater HBI.
IBD clinical improvement continues to be guided by gut flora. A presentation by Hacker from the University of Munich found that enteric enteral nutrition drove a multi-OMIC panel, including a group of protective bacteria, correlating with improved clinical responses. Furthermore, dogs are associated with a lower incidence of altered gut barriers with changes in microbiome composition. Williams Turpin from the University of Toronto presented this finding during the IMIBD section, distinguished abstract plenary on May 23. This session was excellent in the range and depth of presenters, who covered a range of IBD research topics.
Amongst the posters presented that were of interest, Tu1474 showed a clinical response in an open-label enema study of an anti-helminth, Niclosamide, given by enema for ulcerative proctitis/proctosigmoiditis.
Another luminal disorder associated with the disassociation of PRO scoring and histologic response to treatment was presented by Dellon et al., who evaluated clinical and histologic improvements in eosinophilic esophagitis from the three-part liberty EOE TREET study. This study evaluated treatment response to dupilumab for EoE patients at week 24.
Interestingly, the study showed a disconnect between histologic response to treatment (Histologic scoring system) and the absolute change in the Dysphagia symptom questionnaire (DSQ), a PRO-coprimary outcome for the study. This finding is interesting given the similarities to IBD scoring, where lack of correlation with PRO guidance has been an issue.
A presentation by the VQ-HP trialists of a p-CAB (Vonoprazan) was given by a Thai group of investigators led by Tungtrongchitr from Samut Prakan. The p-CABs represent a new treatment class, different from PPIs in that they are more rapidly acting and efficacious than PPI medications. This group found that a quadruple therapy regimen (including bismuth subsalicylate, metronidazole, and tetracycline) eradicated 84.4 % at seven days and 94% at 14 days. This study was significant in that these rates were achieved in geography with high rates of clarithromycin resistance regardless of CYP3A4/5 genotype. More to come from this class of drugs!
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