Introduction

Digestive neuroendocrine tumors (DNETs) are rare and ubiquitous neoplasm of the digestive tract, with an incidence that is increasing significantly in recent years. Special AT-rich sequence-binding protein 2 (SATB2) and the homeotic transcription factor (CDX2) are markers of intestinal differentiation that may be involved in the in the topographic diagnosis of DNET and thus orientate towards the site of the primary NET.

Aims & Methods

The aim of our work was to evaluate the immunohistochemical expression of CDX2 and SATB2 in DNET according to the topography and the histoprognostic factors. We conducted a longitudinal and retrospective study including 39 DNETs. Epidemiological and anatomopathological data according to the 2019 WHO classification were studied. The study of CDX2 and SATB2 was performed by immunohistochemical method. Positivity was considered in the presence of a nuclear immunoreactivity greater than 10%.

Results

The mean age of patients diagnosed with DNETs was 51.4 years with a sex ratio M/F of 0.77. The predilection sites were the small intestine and the appendix, in 33.3% of cases each. CDX2 was expressed in 64% of DNETs. It was positive in 90-100% of small intestine, appendix and colon neuroendocrine neoplasms. SATB2 was expressed in 60% of DNETs. It was found in 100% of appendicular and colorectal neuroendocrine tumors. A weak staining was observed in 69% of small intestine neuroendocrine tumors. Gastric and pancreatic tumors pancreatic tumors did not express CDX2 nor SATB2. This variation in expression was statistically significant (p<0.001). Grade G1 tumors (67%) were in 70% CDX2+/SATB2+. Grade G2/G3 tumors (33%) were in 68% of cases SATB2- without significant difference. The pT1/pT2 DNET (n=19) were CDX2+/SATB2+ in 68%. The pT3/pT4 tumors (n=17) were CDX2- in 35% and SATB2- in 47% without significant difference. Lymph node and distant metastases were found in 28% and 14% of cases respectively. No statistically significant correlation was noted between CDX2 or SATB2 and the presence of lymph node metastases. However, the loss of SATB2 was significantly associated with the metastatic potential (p<0.001).

Conclusion

CDX2 and SATB2 are highly sensitive and relatively specific markers of the digestive tract. They would be useful in the topographic approach of neuroendocrine tumors of unknown origin.

Introduction

To assess the exposure response of NK-1 receptor antagonist tradipitant in the reduction of gastroparesis symptoms in patients with idiopathic gastroparesis in the open label arm of phase 3 study (VP-VLY-686-3301).

The four etiologies of gastroparesis are diabetic, post-surgical, drug-induced, and idiopathic. The idiopathic etiology of gastroparesis is least common, presenting in about 11.3% of patients, which amounts to about 90,000 patients in the United States. Standards set by the FDA define a rare disease or condition as one that affects less than 200,000 people in the United States. This establishes idiopathic gastroparesis as a rare condition, as well as one with a high unmet need for treatment. Patients with gastroparesis have decreased quality of life associated with severe and chronic symptoms and no treatment is currently approved for idiopathic gastroparesis specifically. Tradipitant previously demonstrated efficacy in idiopathic gastroparesis in reducing gastroparesis symptoms in a phase 2 study (VP-VLY-686-2301).

Aims & Methods

The open label arm of Study 3301 enrolled n=531 idiopathic and diabetic gastroparesis patients with delayed gastric emptying, moderate to severe nausea, and at least 1 vomiting episode. Patients received 85 mg tradipitant twice a day for 12 weeks. Nausea was assessed daily using the 5-point Gastroparesis Core Symptom Daily Diary (GCSDD). Overall gastroparesis symptoms were assessed every 2 weeks in clinic using the Gastroparesis Cardinal Symptom Index (GCSI).

An exposure response analysis was performed on a subgroup of patients to control for low drug exposure. We used a threshold of ≤140ng/ml tradipitant blood concentration at any visit to classify participants in the High (n=309) and Low (n=218) PK Populations. Results were further stratified to compare average nausea severity and gastroparesis symptoms at baseline nausea severity scores of ≥2 and ≥2.5 for Low (n=129 and n=89, respectively) and High (n=170 and n=110, respectively) PK subgroups.

Results

Patients in the High PK subgroup had statistically improved nausea severity at Week 12 compared to the Low PK subgroup (-1.19 vs. -0.78, respectively; p<0.0001), including at baseline nausea severity scores of ≥2 (-1.61 vs. -0.98, respectively; p<0.0001) and ≥2.5 (-1.77 vs. -1.03, respectively; p<0.0001). The High PK subgroup also had statistically significant improvement in nausea-free days at Week 12 compared to Low PK (+35.65% vs. +22.56%, respectively; p=0.0002), including at baseline nausea scores of ≥2 (+36.36% vs. 18.15%, respectively; p=0.0002) and ≥2.5 (+33.44% vs. 14.11%, respectively; p=0.0009).

Conclusion

A significant exposure response was seen in idiopathic gastroparesis patients receiving open label tradipitant for 12 weeks. Patients with higher blood levels of tradipitant significantly improved in average nausea severity and in endpoints measuring overall gastroparesis symptoms compared to subjects with low drug blood levels.

Disclosure

Study was sponsored by Vanda Pharmaceuticals, Inc. Authors are employees of Vanda Pharmaceuticals, Inc.

Introduction

Mirikizumab is a p19-directed anti-interleukin-23 antibody approved for treatment of adults with moderately to severely active ulcerative colitis (UC). Here, we report mirikizumab pharmacokinetics and exposure-response in pediatric patients with moderately to severely active UC from the phase-2, multicenter, open-label study SHINE-1 (NCT04004611).

Aims & Methods

Patients aged 2 to <18 years weighing >10kg with a modified Mayo score (MMS) of 4-9 and endoscopic subscore ≥2 received intravenous mirikizumab induction doses (300mg for weight >40kg; 5 or 10mg/kg for weight ≤40kg) every 4 weeks (Q4W) through Week 12. At Week 12, patients achieving MMS clinical response received subcutaneous maintenance doses of mirikizumab 200mg (>40kg), 100mg (>20-≤40kg), or 50mg (≤20kg) Q4W for 36 weeks. Pharmacokinetic parameters were analyzed by nonlinear mixed-effects modeling with fixed allometry for size. Covariate effects on mirikizumab exposure were evaluated using simulation-based estimations. Exposure-response for patients achieving clinical response, remission, and endoscopic response at Weeks 12 and 52 were explored using graphical approaches.

Results

The analysis included 232 samples from 26 patients. Estimated systemic clearance, volume of distribution, and subcutaneous bioavailability were 0.000296 L/hr/kg, 0.069 L/kg, and 49.8%, respectively. Pharmacokinetic model-estimated exposures in all weight groups were similar to those in adult phase-3 studies LUCENT-1 (NCT03518086) and LUCENT-2 (NCT03524092) except for the 10‑mg/kg induction dose, which was 2-fold higher (Figure). In the exposure range studied in SHINE-1, exposure-response analysis using post-hoc grouping by average concentration quartile revealed no improvement trend in clinical response, remission, or endoscopic response and showed similar efficacy to that in adults.

Conclusion

Mirikizumab pharmacokinetic exposures and efficacy results at intended phase-3 doses across all pediatric weight groups were similar to those reported in adults. No patient factors other than weight justify dose adjustment. Exposure-matching to the adult exposure data and exposure-response analysis support a phase-3, weight group-divided dosing strategy in pediatric patients.

Disclosure

Y. Otani, L. Chua, W. Komocsar, A. Larkin and X. C. Zhang are employees and shareholders of: Eli Lilly and Company.

Introduction

Obefazimod is an oral small molecule that has demonstrated short- and long-term efficacy and good safety profile in patients with moderate-to-severe ulcerative colitis (UC) (1,2). Obefazimod modulates inflammation by upregulating a specific anti-inflammatory micro-RNA (miR-124). In humans, obefazimod is metabolized via UGT1A9 as a main active metabolite (N-Glu). We examined whether the pharmacodynamics of obefazimod with regard to miR-124 upregulation in blood of patients receiving obefazimod during a 16-week phase 2b induction study (EudraCT number: 2018-003558-26) were correlated with AUC and Cmax of the parent drug and its metabolite.

Aims & Methods

Absolute quantification (QuantaSoft Pro) of the miR-124 copy number was performed by using droplet digital PCR technology on 205 whole blood samples from 205 patients receiving obefazimod (25, 50, 100 mg once daily) for 16 weeks. For pharmacokinetics assessment (Cmax and AUC of obefazimod and its metabolite), blood samples were collected in all patients on week 16 of study treatment. The correlation between miR-124 upregulation and Cmax and AUC was tested with Spearman's non-parametric correlation analysis.

Results

Daily obefazimod treatment (25, 50, 100 mg) dose dependently increased the number of miR-124 copies in blood of UC patients (Table). miR-124 upregulation at week 16 in blood of obefazimod-treated patients was significantly correlated with AUC for obefazimod and its metabolite. The miR-124 upregulation showed a significant correlation with Cmax of N-Glu, while no significant correlation was observed with the parent compound. There was a dose-dependent correlation between miR-124 upregulation and Cmax of the metabolite.

Number of miR-124 copies - Correlation of miR-124 upregulation and PK parameters

Conclusion

The pharmacodynamics of obefazimod with regard to miR-124 upregulation in blood of patients receiving obefazimod for 16 weeks correlates significantly with AUC and Cmax of N-Glu, and to a lesser extent with the parent drug. These findings are indicative of a dominant effect of N-Glu on miR-124 expression, which is consistent with the longer half-life and higher exposure of the metabolite compared to obefazimod. The lack of significant PKPD correlation between miR-124 increase and PK values with the highest dose of obefazimod suggests a saturation effect.

References

1. Vermeire S, Sands B, Tilg H et al. ABX464 (obefazimod) for moderate-to-severe, active ulcerative Colitis: a phase 2b, double-blind, randomised, placebo-controlled induction trial and 48 week, open-label extension. Lancet Gastroenterol Hepatol 2022, 7 (11): 1024-1035
2. Vermeire S, Sands B, Biguenet S et al. ABX464 (obefazimod) in patients with moderate-to-severe ulcerative colitis: an Interim 48-week the safety and efficacy analysis from an ongoing 96-week open-label maintenance phase 2b study. UEG journal 2022, 10 (S8): p.340

Disclosure

Bruce E Sands reports consulting fees from Abbvie, Alimentiv , Amgen, Arena Pharmaceuticals, Artugen Therapeutics, Astra Zeneca, Boehringer Ingelheim, Boston Pharmaceuticals, Calibr, Celgene, Celltrion, ClostraBio, Equillium, Enthera, Evommune, Fresenius Kabi, Galapagos, Genentech (Roche), Gilead Sciences, GlaxoSmithKline, Gossamer Bio, Index Pharmaceuticals, Innovation Pharmaceuticals, Inotrem, Kaleido, Kallyope, Merck, Morphic Therapeutics, MRM Health, Progenity, Prometheus Biosciences, Prometheus Laboratories, Protagonist Therapeutics, Q32 Bio, Sun Pharma, Surrozen, Target RWE,Teva, TLL Pharmaceutical, Ventyx Biosciences; consulting and speaking fees from Abivax; consulting and speaking fees and other support from Lilly; research grants, consulting and speaking fees and other support from Bristol Myers Squibb, Janssen, Pfizer, Takeda; research grants and consulting fees from Theravance Biopharma; and stock options from Ventyx Biopharma.
Séverine Vermeire has received grants from AbbVie, J&J, Pfizer, Takeda and Galapagos; Séverine Vermeire has received consulting and/or speaking fees from: AbbVie, Abivax, AbolerIS Pharma, AgomAb, Alimentiv, Arena Pharmaceuticals, AstraZeneca, Avaxia, BMS, Boehringer Ingelheim, Celgene, CVasThera, Cytoki Pharma, Dr Falk Pharma, Ferring, Galapagos, Genentech-Roche, Gilead, GSK, Hospira, Imidomics, Janssen, J&J, Lilly, Materia Prima, MiroBio, Morphic, MrMHealth, Mundipharma, MSD, Pfizer, Prodigest, Progenity, Prometheus, Robarts Clinical Trials, Second Genome, Shire, Surrozen, Takeda, Theravance, Tillots Pharma AG, Zealand Pharma.

Introduction

Ulcerative colitis (UC) is a chronic, non-specific inflammatory disease of the bowel of unknown etiology. This disease is characterised by high difficulty in cure, high recurrence and cancer rates, which seriously endangers the lives and health of our population. Taraxasterol (TA), a major constituent of the traditional Chinese medicine dandelion, has been reported in several studies to have good anti-inflammatory and antioxidant activities as well as anti-tumour effects.

Aims & Methods

However, the molecular targets and mechanisms of action of TA against UC have not been fully elucidated.The Swiss Target Prediction, PharmMapper databases were used to obtain relevant targets for the drug TA. Targets for UC were obtained from GeneCards, OMIM, PharmGkb, DrugBank databases. Targets of TA anti-UC identified by intersection of drug target and disease target. The relevant targets of TA anti-UC were uploaded to the String database and the resulting data were imported into Cytoscape 3.9.1 software to construct a protein-protein interaction (PPI) network of drug-disease targets. At the same time, the top 10 hub targets were screened using CytoHubba software. Gene ontology (GO) and Kyoto Encyclopedia of Genomes (KEGG) pathway enrichment analyses were performed on TA anti-UC targets using R software, and molecular docking was performed by Autodock Vina 1.1.2. The GEO dataset was used to analyze the differential mRNA expression of the TA anti-UC top 10 hub gene in UC patients and the normal population. Lipopolysaccharide (LPS)-induced intestinal epithelial cells (NCM460) were used to construct an in vitro cellular inflammation model and a Dextran Sulfate Sodium Salt (DSS) induced acute mouse colitis model. The pivotal targets and key signaling pathways were also validated by RT-qPCR and Western blotting.

Results

A total of 129 relevant targets of TA against UC were obtained, of which the top 10 hub targets were GRB2, PTPN11, SRC, PIK3R1, LCK, EGFR, MAPK1, IGF1, ESR1 and JAK2. The PI3K-Akt pathway was significantly associated with TA treatment of UC as identified by KEGG enrichment analysis. GEO dataset analysis demonstrated that EGFR and GRB2 were upregulated in UC patients, while SRC, PIK3R1 and JAK2 were down-regulated. In vitro experiments revealed that TA treatment reversed the expression of EGFR, GRB2, PIK3R1 and JAK2 differential genes. Furthermore, TA was able to up-regulate the mRNA expression of pro-inflammatory factor IL-10 and decrease the mRNA levels of anti-inflammatory factors IL-6, IL-1β and TNF-α in LPS-induced NCM460 cells. In vivo assay confirmed that TA significantly alleviated DSS-induced colonic inflammation in mice, including reversal of weight loss and shortening of colon length, reduction of DAI score in mice, and improvement of intestinal barrier disruption. In vivo and in vitro experiments have confirmed that TA also inhibits the activation of the PI3K/Akt pathway, thus exerting an anti-inflammatory effect.

Conclusion

TA may play a therapeutic role in UC by inhibiting the PI3K-Akt pathway. EGFR, GRB2, PIK3R1 and JAK2 may be the most relevant potential therapeutic targets for TA in the treatment of UC.

Introduction

Crohn’s disease and ulcerative colitis, two forms of inflammatory bowel disease (IBD) require lifelong treatment and patient monitoring. Current predictors of relapse and therapeutic success have limitations, therefore there is a high unmet need to identify novel biomarkers in IBD. Cytokines may be utilized for this purpose in IBD therefore we aimed to assess and compare the inflammatory cytokine profile of the serum and mucosa of IBD patients and healthy controls in a Phase 2 clinical trial. Furthermore, the presence and predictive potential of the selected markers in fecal samples were assessed to identify Inflammatory bowel diseases (IBD) are defined by unregulated immune response leading to intestinal inflammation. Monitoring approaches for disease of the inflammation are mostly invasive, time-consuming and expensive. Therefore, a simple, rapid and non-invasive test, with ability to differentiate IBD from other gastrointestinal conditions and to monitor disease activity, will have important clinical implications. Our previous cytokine profiling identified that Plasminogen activator inhibitor type 1 (PAI-1) is expressed in IBD patients with active disease, but not in control.

Aims & Methods

Therefore, our aim was to assess the utility of PAI-1 in monitoring disease activity and therapeutic response of IBD patients in different biological samples. Serum, biopsy, and fecal samples were collected from 132 IBD patients and 30 controls without IBD. Inclusion criteria included change of therapy or initiation of new treatment for IBD patients. Organoid cultures (OC) were established from biopsies. Immunofluorescence (IF) staining was used to observe the presence and localization of cytokines. ELISA method was used to define the level of PAI-1 in the mucosa, serum and fecal samples. For the gene expression analysis qRT-PCR was used to observe the relative mRNA change of PAI-1 and other cytokines in the mucosa and OCs.

Results

The applied screening approach detected the presence of plasminogen activator inhibitor 1 (PAI-1) in active IBD. We demonstrated that the serum, mucosal and fecal PAI-1 concentration is elevated in IBD patients showing clinical and endoscopic activity. Additionally, in responder patients the initial PAI-1 level decreased significantly upon successful therapy, whereas it remained unchanged in non-responders. OCs derived from active IBD patients produced higher concentration of PAI-1 compared to the controls suggesting that epithelial cells could be a major source of PAI-1. We also showed that faecal PAI-1 selectively increases in active IBD patients, but not in other organic gastrointestinal diseases.

Conclusion

We successfully demonstrated in a Phase 2 clinical trial that serum, mucosal and fecal PAI-1 expression reflects to the disease activity in IBD, which could be used to disease monitoring and possibly therapeutic response. The correlation between the fecal PAI-1 level and the endoscopic activity promotes that it could be used as a novel non-invasive disease specific fecal biomarker in the IBD diagnosis.

Disclosure

LDN-051 is owned by Ladon Therapeutics Ltd.

Introduction

Most immune-mediated disorders display a degree of heritability, with specific genetic variants linked to disease susceptibility. Variants in Endoplasmic Reticulum Aminopeptidase 2 (ERAP2) have been associated with numerous inflammatory conditions, including Inflammatory Bowel Disease (IBD). As several species (rodents included) lack the ERAP2 gene, functional studies have been relatively limited. Several immunological functions of ERAP2 beyond peptide trimming have been proposed, yet most of these findings have been reported in immune cell populations. As the epithelial involvement in IBD pathogenesis is getting increasingly recognized, we set out to explore the impact of epithelial ERAP2 presence during inflammatory encounter using human-derived colonoids as a model system. To investigate the effect of genotype on ERAP2 expression in different disease states, patient material from a IBD cohort was used to correlate genotype to ERAP2 expression in inflamed and noninflamed colonic biopsies.

Aims & Methods

Two single nucleotide polymorphisms (SNPs) linked to ERAP2 expression (rs2910686/rs2248374) were analyzed in a cohort of IBD patients. Genotypes for both SNPs were correlated with colonic ERAP2 expression levels in noninflamed and inflamed biopsies. Based on rs2910686 genotype, ERAP2-proficient (n=4) and ERAP2-deficient (n=4) colon organoids were established to study differential expression between proficient and deficient donors after proinflammatory stimulation.

Results

Conditioning on genotype reveals upregulation of ERAP2 in the inflamed colon of IBD patients. ERAP2 expression proficiency correlates with rs2910686 genotype. IFNɣ induces colonic epithelial ERAP2 expression. Western blot confirms that mechanisms independent of the frequently studied SNP rs2248374 can cause ERAP2-deficiency. A total of 586 genes involved in various molecular mechanisms are differentially expressed between ERAP2-proficient and -deficient colonoids upon proinflammatory stimulation, including AOC1, CPE, ANPEP and MEP1A (catalytic activity), TNFSF9, MDK, GDF15, ILR6A, LGALS3 and FLNA (regulator activity), SLC40A1 and SLC5A1 (transmembrane transporter activity), FGL2, HMCN2, and MUC17 (extracellular matrix structural constituents).

Conclusion

Our findings demonstrate that ERAP2 expression is significantly upregulated in the inflamed colon of IBD patients, and expression levels correlates with rs2910686 genotype. Although rs2248374 is commonly used to assess ERAP2 expression proficiency, our findings confirm that mechanisms independent of rs2248374 can lead to ERAP2-deficiency. We further demonstrate that stratifying organoid donors based on genotype is a useful way of exploring the impact of genetic variants. Our data support that ERAP2 play a multifaceted role in modulating the inflammatory response in epithelial cells.