Introduction

Data on the long-term benefit of transmural healing (TH) are scarce in children.

Aims & Methods

We investigated the outcomes of pediatric Crohn's disease (CD) patients with TH comparing them to those with mucosal healing (MH) and with “no healing”.
We conducted a prospective, single-center, observational study conducted at the Pediatric Gastroenterology Unit of Sapienza University of Rome. Children with an established diagnosis of CD and under biological therapy undergoing an MRE and an ileocolonoscopy within a 3-month interval were consecutively enrolled. TH was defined as the complete healing of both the mucosa at endoscopy and of the bowel layers at the MRE. In the presence of a normal colonoscopy but an active MRE children were deemed as MH. The group “no healing” (NH) included children with an active endoscopy, regardless of the MRE classification. At 6, 12, and 24 months number disease flares, CD-related hospitalization, CD-related surgery, need for step-up treatment, and occurrence of complications were collected.

Results

93 children were included (mean age 11,2±3,8). Twenty-three (25%) were classified as TH, 27 (29%) as MH and 43 (46%) as NH. The risk of any unfavorable outcome was lower in both TH and MH patients compared to NH (Log Rank p<0.0001 and p=0.002). Children with TH were at lower risk of hospitalization (p=0.02), and complications (p=0.007) compared to those with NH. No difference was found between MH and NH children for the same outcomes. Both TH and MH children were at lower risk of step-up treatment (p<0.0001 and p=0.0002, respectively) compared to NH. TH and MH patients were comparable for all the outcomes evaluated.

Conclusion

Achieving TH in pediatric CD is associated with better outcomes, although the additional benefit over MH alone does not appear significant. However, the persistence of inflammation is associated with worse outcomes in all patients.

Introduction

Antagonism of the interaction between the cellular adhesion integrin ɑ4β7 and endothelial ligand mucosal addressin cell-adhesion molecule-1 (MAdCAM-1) has proven to be relatively safe and effective in the treatment of Crohn’s disease (CD) and ulcerative colitis (UC). Additional benefit may be gained from an ɑ4β7 antagonist given via the subcutaneous (SC) route at extended intervals (eg, every 8 to 12 weeks) during maintenance therapy.

Aims & Methods

The humanized monoclonal IgG1 antibody SPY001 binds to the same ɑ4β7 epitope as vedolizumab and includes a YTE modification within the Fc region to increase its serum half-life via increased affinity for the neonatal Fc receptor (FcRn), thereby favoring recycling into the circulation over degradation. The binding affinity of SPY001 to ɑ4β7 was determined by kinetic exclusion assay (KinExA), surface plasmon resonance, and flow cytometry. In vitro functional activity was determined by inhibition of MAdCAM-1-mediated cell adhesion. In vivo half-life extension was evaluated via pharmacokinetic analysis in Tg276 transgenic mice (hemizygous for human FcRn) and in non-human primates (NHP). PK simulations in humans were based on allometric scaling of SPY001 clearance observed in NHP. Safety was assessed via a good laboratory practice toxicity (GLP-tox) study in NHP.

Results

SPY001 binds specifically to ɑ4β7 and not to the related integrins ɑ4β1 and ɑEβ7. In cell-based binding assays, SPY001 binds ɑ4β7 expressed on the surface of RPMI-8866 cells with an affinity matching that of vedolizumab, but does not bind to Ramos cells expressing ɑ4β1. It demonstrates high affinity for ɑ4β7, with a K_D of <1 nM. Functionally, SPY001 potently inhibits MAdCAM-1-mediated cell adhesion with an IC₅₀ comparable to that of vedolizumab but has no inhibitory activity for VCAM-1-mediated cell adhesion.

In Tg276 mice, the half-life of SPY001 was approximately 12 days compared to approximately 4 days for vedolizumab. In cynomolgus monkeys, the half-life of SPY001 was approximately 22 days following a single SC infusion, substantially longer than the half-life of vedolizumab (~6 days) in the same study. Based on allometric scaling of SPY001 clearance observed in this study, predictive simulations of SPY001 PK in humans suggest that Q8W-Q12W SC dosing will achieve therapeutic exposure in patients across a wide range of body weights and albumin concentrations. In a repeat-dose GLP toxicity study in NHP no adverse or dose limiting toxicities were observed even at the highest dose tested. Both SC and IV administration were well-tolerated and observations related to the administration procedure were similar across doses including controls.

Conclusion

SPY001 is a novel humanized monoclonal IgG1 with an extended half-life relative to that of vedolizumab in Tg276 mice and cynomolgus monkeys. Repeat-dose toxicity studies at doses up to 160 mg/kg showed no SPY001-related adverse events and a safety profile supportive of progression into clinical development. SPY001 offers the potential for effective and safe treatment of CD and UC with the advantage of infrequent SC dosing. Clinical studies are warranted to demonstrate this potential.

Disclosure

EZ, DR, RV, JO, and HS are employees of Paragon Therapeutics.
JF, DN, AS, MR, and OB are employees of Spyre Therapeutics.

Introduction

Most current approaches for therapy for Inflammatory Bowel Disease (IBD) focus on inhibition of excessive inflammation. However, with clinical remission rates for IBD plateauing, new approaches, are needed. The protease, Activated Protein C (APC), can exert a broad range of cytoprotective actions including inhibition of inflammation, stabilization of endothelial and epithelial barriers and suppression of apoptosis. APC shows therapeutic effects in various inflammatory diseases, and its cytoprotective functions often require biased cleavage of protease-activated receptor (PAR)1 and PAR3. Biparetide is a bivalent PAR1:PAR3-derived peptide formed by covalent linkage of PAR1-residues 47-55 to PAR3-residues 51-65 via a 10-mer oligo-Gly peptide. Biparetide in vitro mimics APC’s anti-inflammatory activity.

Aims & Methods

Aim: Our objective was to assess the in vivo therapeutic benefits of intrarectal and intraperitoneal administration of biparetide in a murine preclinical 40kDa dextran sulfate sodium (DSS) model of colitis.
Methods: Eight-week-old female C57Bl/6N mice were given 2% (weight/volume) DSS in drinking water for three 7-day cycles followed by 7 days of regular drinking water to induce colitis. Both biparetide (1, 10 and 50 mg/kg) and scrambled biparetide (peptide with randomized amino acid sequence) were given daily from day 18 to day 41 by concomitant intrarectal (half volume) and intraperitoneal (IP) injection (half volume). Anti-TNFa was administered IP 15mg/kg 3 times per week from day 18 to day 41. Prednisolone was administered IP (1mg/kg) once daily from day 18 to day 42. Control groups included healthy mice and DSS-treated animals receiving only vehicle. Colitis severity was monitored using a disease activity score (DAI) based on daily evaluation of weight, stool consistency, and presence of blood; at study end, endoscopic scoring was performed. Colon length and weight were measured, and histological analysis on formalin-fixed paraffin sections was performed by a blinded pathologist.

Results

DSS effectively induced chronic colitis. Biparetide dose-dependently reduced body weight loss compared to vehicle-dosed DSS-treated mice from day 24 (p<0.01). Biparetide at both 10 and 50 mg/kg significantly improved body weight loss compared to prednisolone (p<0.01) and anti-TNF-a from day 31 (p<0.01), and it was associated with a dose-dependent, significant reduction in DAI score compared with vehicle-dosed DSS-treated mice, e.g., from day 24 (for 10 mg/kg, p<0.01). Biparetide significantly reduced DAI compared with prednisolone (p<0.01) and reduced DAI similar to anti-TNF-a. The peptide’s protective effects against chronic colitis observed at both 10 and 50 mg/kg were accompanied by improvements in colon length shortening and in colon weight/length ratio (p<0.01), with effects comparable to anti-TNF-a. Amelioration of histological and endoscopic parameters of colitis was seen with anti-TNF-a and biparetide (10 and 50mg/kg) treatments.

Conclusion

In this DSS-induced colitis model, biparetide gave dose-dependent improvement in clinical signs and symptoms, reducing body weight loss and improving DAI score. These significant improvements were seen at 10mg/kg and 50mg/kg peptide. Similar improvements were observed during endoscopy and upon histological assessment. Here we demonstrate proof of concept that biparetide is a novel anti-inflammatory peptide that mimics APC’s previously reported in vivo benefits for DSS-induced colitis. Moreover, these data suggest that biparetide merits further evaluation for clinical translation for inflammatory pathologies.

Introduction

The etiology and pathogenesis of inflammatory bowel disease (IBD), which includes Crohn's disease (CD) and ulcerative colitis (UC) are complex and the mechanisms that lead to the development of these diseases remain unclear. Extracellular vesicles (EVs) are small particles covered with a cell membrane, originating from the emitting cell, excreted into the extracellular medium, and subsequently captured by receptor cells. EVs have a role in multiple diseases and they could also have a function in IBD pathogenesis. Therefore, the analysis of EVs isolated from the serum of newly diagnosed IBD patients (before starting any treatment) may represent an appropriate experimental approach to elucidate their role in IBD pathogenesis.

Aims & Methods

We aimed to evaluate EVs’ composition and potential effects in the pathogenesis of IBD. To assay this, EVs were isolated by size exclusion chromatography from the 500 µl of serum from 100 patients with IBD (50 patients with CD and 50 patients with UC) recently diagnosed and 50 healthy controls (HC). Then, the protein loaded in the EVs was characterized by proteomics and their size and concentration in serum by Nanoparticle tracking analysis (NTA). The biological function of EVs and alterations in signaling pathways related to IBD were determined using Ingenuity Pathways Analysis (IPA) to analyze the OMICs results.

Results

A total of 1,100 proteins have been identified, of which 105 proteins were differentially expressed by patients with CD versus HC, 111 proteins by patients with UC versus HC, and 32 proteins by patients with UC versus CD. IPA analysis revealed that proteins carried in EVs are involved in the dysregulation of immune pathways such as the acute phase response, LXR/RXR activation pathway, and the complement pathway. These pathways were regulated differentially in IBD patients compared with HC, but also when the CU group was compared with the CD group being upregulated nuclear receptors signaling and cytotoxicity pathways.

Conclusion

EVs carry proteins that can be involved in the dysregulation of the immune system in IBD; this effect would be different in UC and CD since their EVs show a differential profile. Consequently, EVs may play role in IBD pathogenesis and source of strong biomarkers candidates for diagnosis in UC and CD. Further studies on their specific function during IBD are warranted.