Introduction

Inflammatory Bowel Diseases (IBD) are chronic inflammatory disorders characterised by alterations of acute relapses and remission. The past decades have brought substantial advances in the pharmacological management of IBD by the introduction of immunosuppressive agents, biologics and lately small molecules. Although, the sustained efficacy of the currently available anti-inflammatory therapies is still far from optimal. Therefore, the development of novel therapies represents a major unmet clinical need in this field. Recently the enrichment of the coagulation pathway genes and among these, plasminogen activator inhibitor 1 (PAI-1) was described in IBD, whereas PAI-1 emerged as a link between the epithelium and inflammation. Moreover, the genetic deletion of PAI-1 impaired the severity of experimental colitis in mice.

Aims & Methods

Based on these, our aim was to develop and test novel PAI-1 inhibitors for the treatment of IBD. Novel, peptide-based PAI-1 inhibitors were designed and screened in silico, then the selected ones were synthetized using the ixPeptide® platform. The inhibitory potential of the peptides was determined by an in vitro PAI-1 activity assay. Cytotoxicity was monitored in vitro in Hela cells with the CellTiter Glo assay. Based on the in vitro results LDN-071 was selected for further analysis. Experimental colitis was induced in mice with 3% DSS and after the induction of colitis 10 mg/bwkg LDN-071 was administrated per os for four consecutive days. The changes of body weight, spleen weight and colon length were measured. Haematoxylin eosin (HE) and Periodic acid-Schiff (PAS) staining were performed for histology. ELISA and qRT-PCR measurements were applied to analyse the mucosal cytokine expressions. In vivo toxicity of LDN-071 was determined in mice.

Results

LDN-071 significantly inhibited PAI-1 in vitro without decreasing the cell viability in a concentration range of 1µM-1mM. The administration of 10 mg/bwkg LDN-071 in the DSS-treated mice prevented the body weight loss, the development of bloody diarrhoea, the decrease of colon length and increase of the spleen weight, which were displayed by the DSS+vehicle-treated animals. The histological analysis of the colon revealed that DSS treatment induced a severe transmural inflammation, ulceration, loss of crypt structures and goblet cell depletion. Importantly, all of these parameters were significantly impaired by the administration of 10 mg/bwkg LDN-071. Additionally, mucosal gene and protein expressions of TNF-α, IL-1β and IL-6 were significantly impaired by PAI-1 inhibition. Importantly, no signs of toxicity were LDN-071 observed in mice exposed to 100 mg/bwkg LDN-071 for 7 days.

Conclusion

Our results showed that LDN-071, a novel peptide-based inhibitor of PAI-1. It significantly reduces the severity of experimental colitis in mice. We propose that the inhibition of PAI-1 could be a potential novel therapeutic strategy in IBD.

Disclosure

LDN-071 PAI-1 inhibitor is owned by Ladon Therapeutics Ltd.

Introduction

Inflammatory bowel disease (IBD) is characterized by chronic inflammation due to an uncontrolled immune response orchestrated through, i.e. neutrophils. The basement membrane acts as a front-line defense promoting tissue integrity, where the α-3 chain of type IV collagen is solely expressed on the outermost layer of the mucosa. Detection of subclinical ulceration is crucial since early-stage IBD presents a unique window of opportunity for intervention, as the disease might become a self-sustaining process once deep inflammation becomes established. We therefore, wanted to develop a biomarker reflecting early tissue injury, aiding in the implementation of prompt treatment.

Aims & Methods

A competitive enzyme-linked immunosorbent assay quantifying a human neutrophil elastase (HNE) degraded fragment of type IV collagen α-3 chain was developed (C4A3-HNE). Dilution- and spiking recovery, inter- and intra-variability, and interference were evaluated. Acceptance criteria for technical validation were a recovery of 100% ±25 and an inter-intra variability of <15%. Commercial serum samples were purchased from ProteoGenex. Biological relevance was validated in an observational study from Odense University Hospital (OUH) and healthy controls. Groups were compared using Kruskal Wallis (Dunn‘s corrected).

Results

The technical validation of the C4A3-HNE assay demonstrated acceptable results for recovery, variation, and interference. Biological relevance was assessed in commercial IBD samples and healthy donors. C4A3-HNE was elevated in both CD and UC compared to healthy (p=0.001 and <0.0001)(AUC [95% CI]: 0.820 [0.669-0.971]; 0.875 [0.775-1.000]). The results were validated in an independent cohort of IBD patients (both p<0.0001). For UC, analysis showed that compared to patients in endoscopic remission, C4A3-HNE is elevated in patients with mild endoscopic activity, decreasing dose-dependently for moderate and severe disease (T1). Fecal calprotectin and CRP levels were also lower in IBD patients with high levels of C4A3-HNE (T1). With a cut-off value of 54.1 ng/ml, C4A3-HNE could significantly discriminate between mild and severe endoscopic disease (T1).

Conclusion

Our study demonstrates the biological and possible clinical relevance of the novel C4A3-HNE biomarker. The biomarker is elevated in patients with IBD compared with healthy, and high levels may reflect early mucosal damage in patients with UC. Furthermore, inflammatory markers were lower in IBD patients with high levels of C4A3-HNE, pointing towards high levels being indicative of early disease. C4A3-HNE may provide early detection of mucosal damage or prediction of relapse; however, further studies are required to assess the clinical validity of this biomarker.

Disclosure

MA, MP, MK, and JM are employees of Nordic Bioscience A/S. MK owns stocks in Nordic Bioscience A/S.

Introduction

Carbohydrate sulfotransferase 15 (CHST15) is an enzyme biosynthesizing sulfated matrix glycosaminoglycan that modulates tissue remodeling.

Aims & Methods

We evaluated the efficacy of add-on submucosal injections of GUT-1, the RNA oligonucleotide inhibitor of CHST15, to ongoing tumor necrosis factor (TNF) antagonist treatment in patients with moderate-to-severe ulcerative colitis (UC) and insufficient response to TNF antagonists.
This was an open-label study of 250 nM of GUT-1, which was applied by endoscopic submucosal injections at weeks 0, 2 and 4 in five UC patients who lost response during maintenance treatment to TNF antagonists. The primary endpoint was the rate of endoscopic improvement at week 6 and secondary endpoints included the rates of clinical remission. All patients received follow-up observation with continuous maintenance treatment by the same TNF antagonists till the time of clinical recurrence, defined by rectal bleeding and endoscopic examination, or for overall 48 weeks (Clinical trial Registration Number: UMIN000020900).

Results

At baseline, all included patients showed insufficient clinical and endoscopic response to ongoing TNF antagonist treatment (3 for infliximab and 2 for adalimumab), as measured by modified Mayo Score (mMS) of 7.8 (95%CI: 6.2 to 9.4), Endoscopic Subscore of 2.4 (95%CI: 1.7 to 3.1), Stool Frequency Subscore of 2.8 (95%CI: 2.2 to 3.4) and Rectal Bleeding Subscore of 2.6 (95%CI: 1.9 to 3.3). At week 6, Endoscopic Subscore reduced to 1.0 (95%CI: 0.1 to 1.9) and rate of endoscopic improvement was 80% (n=4/5). mMS reduced to 1.3 (95%CI: 0.4 to 3.2) and rate of clinical remission was 60% (n=3/5). Exploratory, Nancy histological index reduced to 1.8 (95%CI: 0.2 to 3.4) at week 6 from 3.6 (95%CI: 2.9 to 4.3) at baseline. Three patients did not show any signals of clinical recurrence for 48 weeks. All three corticosteroid-dependent patients showed no corticosteroid exposure for at least 20 weeks after achieving clinical remission. During the follow-up period, clinical recurrence was observed in one patient at week 36 and another at week 44.

Conclusion

Add-on multiple injections of GUT-1 to ongoing TNF antagonist treatment was able to induce rapid and durable clinical responses in patients with TNF antagonist-refractory UC. GUT-1 was well tolerated by the patients.

Introduction

Inflammatory bowel disease (IBD) is an idiopathic and chronic disorder that includes ulcerative colitis (UC) and Crohn’s disease (CD). Both diseases are different but show an uncontrolled intestinal immune response that generates tissue inflammation. Dendritic cells (DC) are phagocytic professional antigen presenting cells that link the innate and adaptive immune systems. Indeed, they are the only cell type able to stimulate naïve T cells generating an antigen-specific immune response. In humans, DC can be divided into plasmacytoid (pDC) and c conventional type 1 and 2 (cDC1, cDC2). Although cDC migration towards the GI mucosa is enhanced in IBD, the mechanisms underlying these migrations and whether biological drugs can modulate them are currently unknown.

Aims & Methods

This study aimed to analyze DC migratory capacity towards the GI mucosa, and whether biological drugs with different mechanisms of action can modulate this process in health and IBD.This is a cross-sectional observational postmarketing study where the modulatory effect of different biological treatments on samples from patients with an endoscopic diagnosis of IBD and healthy controls was studied ex vivo. Peripheral blood mononuclear cells (PBMC) were obtained from 15 patients per group and were cultured in presence of golimumab or ustekinumab. Following culture, surface markers expression was determined, assessing the differential effect of biological drugs (if any) over the DC subsets in the different groups. After that, the migratory capacity of circulating DC towards CCL2, CCL25, and MadCam1 from the different study groups was determined. Finally, we evaluated the DC migratory capacities in presence of biological drugs or with culture media alone.

Results

The cDC2 subset showed higher expression levels of β7 and CCR5 compared to cDC1. Golimumab and ustekinumab did not modify the expression of the homing markers in any studied subset in pDC and cDC2.On the contrary, in cDC1 both golimumab and ustekinumab increased CCR6 expression in qCD patients and CCR9 in aUC patients. Regarding to the migratory capacities of the different DC subsets toward intestinal chemoattractants ustekinumab decreased the migratory capacity of cDC2 from CD patients towards a medium supplemented with MadCam1 and increases toward CCL2 in case of cDC1 from CU. In the case of migratory capacities of cDC2 from HC were increased by ustekinumab and golimumab toward CCL2 and CCL25 just in case of golimumab.

Conclusion

cDC2 showed more migratory profile markers than other DC populations. Golimumab and ustekinumab modify the expression of the homing markers just in cDC1 subset. Nevertheless, ustekinumab and golimumab modify the migratory capacities of cDC in IBD patients and HC, but do not exert any effect on pDC. These effects occur in a different manner in CD and UC indicates that the behavior of cDC is different in CD and UC, and that the migration capacity of this subset is not dependent exclusively on homing markers.

Introduction

Therapeutic progress in inflammatory bowel disease (IBD) is limited by the lack of understanding of the pathophysiology and the mechanisms involved in response or lack/loss of response to treatments. IBD patients are treated with anti-inflammatory drugs, including biologics such as anti-tumor necrosis factor (TNF) agents, which have been crucial in achieving steroid-free remission and prevention of long-term complications. However, a significant subgroup of patients becomes refractory to these biologicals due to the development of immunogenicity, characterized by the presence of anti-drug antibodies (ADAs). The antibody production and peripheral tolerance are initiated and maintained within lymphoid organs, such as the peripheral lymph nodes, but the exact role of immune cells in these lymphoid structures and whether they are involved in anti-drug antibody (ADA) formation is unknown.

Aims & Methods

We aimed to unravel the pathophysiology behind the development of anti-drug antibodies. Therefore, we performed ultrasound-guided inguinal lymph node needle biopsies from which we isolated leukocytes along with PBMCs from the same patients. Leukocyte populations were analyzed at single cell level via high dimensional phenotyping through mass cytometry (CyTOF).

Results

Using this unique approach, we have so far results from 4 Crohn’s Disease (CD) patients with ADAs (75% females, 50% active disease) and 4 without ADAs (50% females, 75% active disease). Active disease was defined, as an observation of an elevated CRP (c-reactive protein) (>5 mg/L) and/or calprotectin >250 (mg/kg), including symptoms (Harvey-Bradshaw index score > 4 or disease activity index score-CDAI >150).
The proportion of CD4⁺ TEMRA (terminally differentiated effector memory T-cells), CD4⁺ effector and central memory T-cells were increased in the peripheral lymph nodes of patients that developed immunogenicity. Mature NK cells, classical and non-classical monocytes were also increased. Furthermore, the levels of the alpha-4 integrin expression were higher in the lymph node T-lymphocytes, as well as, in the lymph node naïve and memory B-cell subsets in the patient group with ADAs.

Table: Cytometry and Biochemical Characteristics.

Conclusion

Lymph node T-helper cells, monocytes and NK cells potentially play a role in the development ADAs in IBD patients treated with biologics. Although, there was no significant difference in the proportion of naïve and memory B-cells, our findings concerning the alpha-4 integrin expression levels also indicate that both lymph node T and B-lymphocytes, are possibly characterized by a higher migratory potential during immunogenicity conditions.

References

1. Stein RE, Lee DY, Leonard MB, et al. The association between drug levels, anti-drug antibodies, and therapeutic response during infliximab therapy in pediatric Crohn’s disease. J Crohns Colitis 2014; 8: S434.
2. Bodini G, Savarino V, Dulbecco P, et al. The influence of anti-adalimumab antibodies on adalimumab trough levels, TNF-alpha levels and clinical outcome. J Crohns Colitis 2014; 8: S42
3. Stefan S, Sandborn WJ, Choi J, et al. Anti-drug antibodies separate responses of markers of inflammation (c-reactive protein, fecal calprotectin) in Crohn’s disease patients treated with certolizumab pegol. Inflamm Bowel Dis 2014; 20: S68.
4. Strand V, Balsa A, Al-Saleh J, et al. Immunogenicity of Biologics in Chronic Inflammatory Diseases: A Systematic Review. BioDrugs. 2017;31(4):299-316. doi:10.1007/s40259-017-0231-8.
5. Brun MK, Goll GL, Jørgensen KK, et al. Risk factors for anti-drug antibody formation to infliximab: Secondary analyses of a randomised controlled trial. J Intern Med. 2022;292(3):477-491. doi:10.1111/joim.13495.

Disclosure

The authors state no conflict of interest.

Introduction

Cobitolimod (MW 5925.18 Da) is a DNA-based oligonucleotide functioning as an immunomodulatory Toll-like receptor 9 agonist. Cobitolimod is in phase III clinical development as a new therapy for moderate to severe left-sided ulcerative colitis (UC). This phase Ib study aimed to evaluate the pharmacokinetics (PK), safety and tolerability of rectally administered cobitolimod in patients with moderate to severe UC.

Aims & Methods

The phase Ib open-label study was conducted at a single center in Sweden (NCT05404074). The patients had moderate to severe UC defined by a 3-component Mayo score of 5 to 9, with an Investigator read endoscopic subscore ≥2, and with stool frequency and rectal bleeding subscores each ≥1. Patients received one cobitolimod enema (500 mg/50 ml) at week 0, and blood samples for PK analysis were collected pre-dose, 15 min, 30 min, 1h, 2h, 4h, 8h, 12h and 24h after dosing. Patients received a second cobitolimod enema (500 mg/50 ml) at week 3, and at week 6 the degree of clinical remission was evaluated. Clinical remission was defined by the 3-component Mayo score with a rectal bleeding subscore = 0, a stool frequency subscore ≤1 (≥1 point decrease from baseline), and an Investigator read endoscopic subscore ≤1. Patients in clinical remission at week 6 received a third cobitolimod enema (500 mg/50 ml), and blood samples were collected for a second PK analysis as described above. The primary endpoint was PK parameters: maximum plasma concentration (C_max), time to C_max (T_max), area under the curve from 0 to timepoint t (AUC_t) and half-life (T_1/2). Secondary endpoints included safety and tolerability.

Results

Eight patients with active disease were enrolled in the study and included in the safety analysis set. One patient was excluded from the pharmacokinetic analysis set (PKAS) due to an immediate bowel movement following administration. Of the 7 patients included in the PKAS, 4 patients achieved clinical remission at week 6. Rectal administration of 500 mg cobitolimod at week 0 resulted in median C_max of 21.7 ng/ml, median T_max of 1h, median T_last of 4h, and median AUC_0-last of 71.7 h*ng/ml (n=7). For the 4 patients in remission at week 6, corresponding numbers were: median C_max of 15.5 ng/ml, median T_max of 0.5h, median T_last of 4h and median AUC_0-last of 27.6 h*ng/ml. T_1/2 was <2.5h both at week 0 and week 6.
In total, 24 adverse events occurred in the study, out of which the majority was mild and judged as unlikely related to study drug. No serious adverse events were reported.

Table 1. PK parameters per patient

Conclusion

The study demonstrates that rectally administered cobitolimod results in a low systemic exposure of short duration both in patients with active disease and in clinical remission. Cobitolimod was safe and well tolerated at a dose of 500 mg.

Disclosure

Thomas Knittel is a consultant for and a shareholder in InDex Pharmaceuticals, Sweden. Pernilla Sandwall is a former employee and a shareholder in InDex Pharmaceuticals, Sweden. Christine Dieterich Johansson is employed by InDex Pharmaceuticals, Sweden. Arezou Zargari is employed by and a shareholder in InDex Pharmaceuticals, Sweden. Johan Bring is a consultant for InDex Pharmaceuticals, Sweden. Per Hellström receives consultancy fees from: Clinical trial consultants, Sweden; ROSE pharma, USA; Pharmanovia, Denmark; Swedish Agricultural University, Uppsala; Pharmacosmos, Denmark; Stockholm Diabetes Association, Sweden; Celltrion, Finland; Mag-tarmförbundet, Sweden; Karolinska Institutet, Sweden; Bristol-Myers Squibb, Sweden; ClinSmart, Sweden; InDex Pharmaceuticals, Sweden; Takeda pharmaceutical company; Mediahuset, Sweden; Bonnier Healthcare Sweden; Folkuniversitetet, Stockholm, Sweden; Biogaia, Stockholm, Sweden; Norgine, Denmark; Nanologica AB, Södertälje, Sweden.

Introduction

Tofacitinib is an oral small molecule Janus kinase inhibitor for the treatment of ulcerative colitis (UC). Histological outcomes and the immune landscape were assessed in an UC patient cohort at baseline and after 8 weeks tofacitinib.

Aims & Methods

In this prospective study, 40 patients with moderate to severely active UC received tofacitinib 10 mg twice daily for 8 weeks. Clinical, endoscopic and histological outcomes were assessed at baseline and week 8 and colon biopsies were stained for JAK1-3, Tyrosine kinase 2 (TYK2) and Signal transducer and activator of transcription (STAT) 1-6 total protein expression using immunohistochemistry (IHC). Histological remission was defined as a Robarts Histopathology Index (RHI) ≤3 points without mucosal neutrophils and histological response as 50% decrease in RHI compared to baseline. Response was defined as histological remission and endoscopic Mayo score (EMS) ≤1 (histo-endoscopic mucosal improvement). Biopsies were scored by a blinded pathologist. Whole slide images with multiple biopsies per patients were stained using IHC, analyzed using automated cell detection (QuPath) and quantified in percentages by dividing the number of positive stained cells by the total number of cells on the slide. Outcomes were compared between responders and non-responders (NR).

Results

Out of 40 patients, 26 (65%) had severe endoscopic disease (EMS 3) with a median RHI of 14. Thirty-one patients (78%) had failed prior anti-Tumor Necrosis Factor (anti-TNF) agents and 18 (55%) failed vedolizumab. At week 8, 23 patients (58%) achieved histological remission, 34 (85%) histological response and 15 (38%) histo-endoscopic mucosal improvement. A significant decline in RHI compared to baseline was observed after 8 weeks both in responders (14 vs 0, p<0.001) and NR (15 vs 6, p=0.002). In the entire cohort, total STAT1 (p<0.001), STAT3 (p=0.002) and STAT5 (p=0.026) expression significantly decreased after 8 weeks treatment compared to baseline, which was not different between responders and NR (Table). However, responders to tofacitinib expressed significantly lower total STAT1 levels compared to NR at 8 weeks (p<0.001). Likewise, JAK2 (p=0.008) and total STAT2 expression (p=0.004) were significantly lower in responders compared to NR at 8 weeks, although no significant decrease compared to baseline was observed. A trend towards lower baseline JAK1, JAK2 and total STAT4 expression and higher total STAT6 expression was seen in responders compared to NR.

Conclusion

Tofacitinib resulted in histological response in the majority of UC patients and led to a substantial decline of total STAT1, STAT3 and STAT5 expression both in responders and NR. Yet, after 8 weeks significantly lower total STAT1 levels were observed in responders compared to NR. Responders tended to express lower JAK1, JAK2 and total STAT4 and higher total STAT6 levels at baseline.

Disclosure

This study was funded and supported by Pfizer.