Randomised clinical trial: a phase 1, dose-ranging study of the anti-matrix metalloproteinase-9 monoclonal antibody GS-5745 versus placebo for ulcerative colitis

Comparative Efficacy of Biologics and Small Molecule in Ulcerative Colitis: A Systematic Review and Network Meta-analysis

BACKGROUND & AIMS

Treatment options for moderate to severe ulcerative colitis (UC) are increasing rapidly, but the lack of comparative efficacy trials makes treatment choices a clinical challenge. This network-meta-analysis aimed to compare the relative efficacy of biologics and small molecules in achieving remission in patients with moderate to severe UC.

METHODS

The literature was searched up to May 2024. Phase 3 placebo or active comparator randomized controlled trials were included. The primary outcome was induction and maintenance of endoscopic improvement (Mayo Endoscopic Score [MES] ≤1). Secondary outcomes were the induction and maintenance of clinical remission, endoscopic (MES = 0) and histological remission. A sub-analysis was performed based on the randomized controlled trial design and previous exposure to biologic therapy.

RESULTS

We identified 36 studies that met our inclusion criteria, with 14,270 patients with UC. Upadacitinib ranked highest in inducing clinical remission (99.6%), and endoscopic improvement (99.2%), followed by risankizumab (91.4%) and (82.3%), respectively. In maintenance of endoscopic improvement, upadacitinib ranked first (98.6%) followed by filgotinib 200 mg (79.2%). Risankizumab ranked first in the induction of histological remission (89.4%), followed by guselkumab (88.3%). Upadacitinib ranked first (93.1%) in maintaining histological remission, followed by guselkumab (89.5%).

CONCLUSION

Upadacitinib appears to be superior to other therapies in achieving clinical remission, endoscopic improvement and remission, and histological remission. Furthermore, novel biologics such as risankizumab and guselkumab ranked high in achieving these outcomes. This study highlights the efficacy of small molecule drugs and novel selective interleukin-23s as alternatives to other biologics.

Matrix metalloproteinases in intestinal fibrosis

Intestinal fibrosis is a common complication in patients with inflammatory bowel disease [IBD], in particular Crohn's disease [CD]. Unfortunately, at present intestinal fibrosis is not yet preventable, and cannot be treated by interventions other than surgical removal. Intestinal fibrosis is characterized by excessive accumulation of extracellular matrix [ECM], which is caused by activated fibroblasts and smooth muscle cells. Accumulation of ECM results from an imbalanced production and degradation of ECM. ECM degradation is mainly performed by matrix metalloproteinases [MMPs], enzymes that are counteracted by tissue inhibitors of MMPs [TIMPs]. In IBD patients, MMP activity [together with other protease activities] is increased. At the same time, CD patients have a generally lower MMP activity compared to ulcerative colitis patients, who usually do not develop intestinal strictures or fibrosis. The exact regulation and role[s] of these MMPs in fibrosis are far from understood. Here, we review the current literature about ECM remodelling by MMPs in intestinal fibrosis and their potential role as biomarkers for disease progression or druggable targets.

Effect of huankuile on colon injury in rats with ulcerative colitis by reducing TNF-α and MMP9

OBJECTIVE

To explore the mechanism of huankuile (HKL) in colon injury repair in rats with ulcerative colitis (UC).

METHODS

Fifty SPF Wistar male rats were divided randomly into a normal group, a negative control group, an HKL intervention group ('HKL group') and a 5-aminosalicylic acid intervention group ('5-ASA group'). After 14 days of intervention with corresponding drugs, pathological scores were obtained using the results of immunohistochemical staining; morphological changes were observed by hematoxylin-eosin staining, and the mRNA expression levels of tumour necrosis factor-α (TNF-α), matrix metalloproteinase 9 (MMP9) and interleukin-13 (IL-13) were detected by real-time quantitative PCR.

RESULTS

After the successful construction of the rat model, it was compared with the rats in the normal group. In the negative group, it was found that the expression of TNF-α and MMP9 was significantly increased in the colonic mucosal epithelia of the rats, the pathological score was significantly increased (P < 0.05), and the mRNA expression levels of TNF-α, MMP9 and IL-13 were increased (P < 0.05). After treatment with HKL, the colonic morphology of the rats returned to normal, the expression of TNF-α and MMP9 in the colonic mucosal epithelium of the rats returned to normal, the pathological score grade was significantly reduced (P < 0.05), and the mRNA expression levels of TNF-α, MMP9 and IL-13 were reduced; these results were largely consistent with those of the normal group, with no statistically significant difference.

CONCLUSION

HKL effectively improved the general symptoms and tissue injury in UC rats, and the therapeutic effect was better than that of 5-ASA group. Ulcerative colitis in rats increased the expression of TNF-α, MMP9 and IL-13. HKL repaired UC-induced colonic injury in rats by decreasing the expression of TNF-α, MMP9 and IL-13.

Selected Cytokines and Metalloproteinases in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a collective term for two diseases: ulcerative colitis (UC) and Crohn's disease (CD). There are many factors, e.g., genetic, environmental and immunological, that increase the likelihood of these diseases. Indicators of IBDs include extracellular matrix metalloproteinases (MMPs). The aim of this review is to present data on the role of selected cytokines and metalloproteinases in IBD. In recent years, more and more transcriptomic studies are emerging. These studies are improving the characterization of the cytokine microenvironment inside inflamed tissue. It is observed that the levels of several cytokines are consistently increased in inflamed tissue in IBD, both in UC and CD. This review shows that MMPs play a major role in the pathology of inflammatory processes, cancer, and IBD. IBD-associated inflammation is associated with increased expression of MMPs and reduced ability of tissue inhibitors of metalloproteinases (TIMPs) to inhibit their action. In IBD patients in tissues that are inflamed, MMPs are produced in excess and TIMP activity is not sufficient to block MMPs. This review is based on our personal selection of the literature that was retrieved by a selective search in PubMed using the terms "Inflammatory bowel disease" and "pathogenesis of Inflammatory bowel diseases" that includes systematic reviews, meta-analyses, and clinical trials. The involvement of the immune system in the pathophysiology of IBD is reviewed in terms of the role of the cytokines and metalloproteinases involved.

Identification of potential diagnostic biomarkers for tenosynovial giant cell tumour by integrating microarray and single-cell RNA sequencing data

PURPOSE

Tenosynovial giant cell tumour (TGCT) is a benign hyperplastic and inflammatory disease of the joint synovium or tendon sheaths, which may be misdiagnosed due to its atypical symptoms and imaging features. We aimed to identify biomarkers with high sensitivity and specificity to aid in diagnosing TGCT.

METHODS

Two scRNA-seq datasets (GSE210750 and GSE152805) and two microarray datasets (GSE3698 and GSE175626) were downloaded from the Gene Expression Omnibus (GEO) database. By integrating the scRNA-seq datasets, we discovered that the osteoclasts are abundant in TGCT in contrast to the control. The single-sample gene set enrichment analysis (ssGSEA) further validated this discovery. Differentially expressed genes (DEGs) of the GSE3698 dataset were screened and the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of DEGs were conducted. Osteoclast-specific up-regulated genes (OCSURGs) were identified by intersecting the osteoclast marker genes in the scRNA-seq and the up-regulated DEGs in the microarray and by the least absolute shrinkage and selection operator (LASSO) regression algorithm. The expression levels of OCSURGs were validated by an external dataset GSE175626. Then, single gene GSEA, protein-protein interaction (PPI) network, and gene-drug network of OCSURGs were performed.

RESULT

22 seurat clusters were acquired and annotated into 10 cell types based on the scRNA-seq data. TGCT had a larger population of osteoclasts compared to the control. A total of 159 osteoclast marker genes and 104 DEGs (including 61 up-regulated genes and 43 down-regulated genes) were screened from the scRNA-seq analysis and the microarray analysis. Three OCSURGs (MMP9, SPP1, and TYROBP) were finally identified. The AUC of the ROC curve in the training and testing datasets suggested a favourable diagnostic capability. The PPI network results illustrated the protein-protein interaction of each OCSURG. Drugs that potentially target the OCSURGs were predicted by the DGIdb database.

CONCLUSION

MMP9, SPP1, and TYROBP were identified as osteoclast-specific up-regulated genes of the tenosynovial giant cell tumour via bioinformatic analysis, which had a reasonable diagnostic efficiency and served as potential drug targets.

The Role of MMP-9 and MMP-9 Inhibition in Different Types of Thyroid Carcinoma

Matrix metalloproteinase-9 (MMP-9), one of the most investigated and studied biomarkers of the MMPs family, is a zinc-dependent proteolytic metalloenzyme whose primary function is degrading the extracellular matrix (ECM). It has been proved that MMP-9 expression elevates in multiple pathological conditions, including thyroid carcinoma. MMP-9 has a detectable higher level in malignant or metastatic thyroid tumor tissues than in normal or benign tissues and acts as an additional marker to distinguish different tumor stages because of its close correlations with clinical features, such as lymph node metastasis, TNM stage, tumor size and so on. Natural and non-natural MMP-9 inhibitors suppress its expression, block the progression of diseases, and play a role in therapy consequently. MMP-9 inhibitory molecules also assist in treating thyroid tumors by suppressing the proliferation, invasion, migration, metastasis, viability, adhesion, motility, epithelial-mesenchymal transition (EMT), and other risk factors of different thyroid cancer cells. In a word, discovering and designing MMP-9 inhibitors provide great therapeutic effects and promising clinical values in various types of thyroid carcinoma.

Multifunctional hydrogels based on chitosan, hyaluronic acid and other biological macromolecules for the treatment of inflammatory bowel disease: A review

Hydrogel is a three-dimensional network polymer material rich in water. It is widely used in the biomedical field because of its unique physical and chemical properties and good biocompatibility. In recent years, the incidence of inflammatory bowel disease (IBD) has gradually increased, and the disadvantages caused by traditional drug treatment of IBD have emerged. Therefore, there is an urgent need for new treatments to alleviate IBD. Hydrogel has become a potential therapeutic platform. However, there is a lack of comprehensive review of functional hydrogels for IBD treatment. This paper first summarizes the pathological changes in IBD sites. Then, the action mechanisms of hydrogels prepared from chitosan, sodium alginate, hyaluronic acid, functionalized polyethylene glycol, cellulose, pectin, and γ-polyglutamic acid on IBD were described from aspects of drug delivery, peptide and protein delivery, biologic therapies, loading probiotics, etc. In addition, the advanced functions of IBD treatment hydrogels were summarized, with emphasis on adhesion, synergistic therapy, pH sensitivity, particle size, and temperature sensitivity. Finally, the future development direction of IBD treatment hydrogels has been prospected.

Characterization of Active MMP9 in Chronic Inflammatory Diseases Using a Novel Anti-MMP9 Antibody

Matrix metalloproteinase 9 (MMP9), a protease implicated in multiple diseases, is secreted as an inactive zymogen and requires proteolytic removal of the pro-domain for activation. The relative levels and functionality of the pro- and active-MMP9 isoforms in tissues are not characterized. We generated a specific antibody that distinguishes an active form of MMP9, F107-MMP9, from the inactive pro-MMP9 isoform. Using multiple in vitro assays and specimen types, we show that F107-MMP9 expression is localized and disease-specific compared with its more abundant parental pro-form. It is detected around sites of active tissue remodeling, including fistulae of inflammatory bowel and dermal fissures in hidradenitis suppurativa, and is expressed by myeloid cells, including macrophages and neutrophils. Together, our findings provide insights into the distribution and potential role of MMP9 in inflammatory diseases.

Integrated analysis of multiple microarray studies to establish differential diagnostic models of Crohn's disease and ulcerative colitis based on a metalloproteinase-associated module

Background

The ulcerative colitis (UC) and Crohn's disease (CD) subtypes of inflammatory bowel disease (IBD) are autoimmune diseases influenced by multiple complex factors. The clinical treatment strategies for UC and CD often differ, indicating the importance of improving their discrimination.

Methods

Two methods, robust rank aggregation (RRA) analysis and merging and intersection, were applied to integrate data from multiple IBD cohorts, and the identified differentially expressed genes (DEGs) were used to establish a protein-protein interaction (PPI) network. Molecular complex detection (MCODE) was used to identify important gene sets. Two differential diagnostic models to distinguish CD and UC were established via a least absolute shrinkage and selection operator (LASSO) logistic regression, and model evaluation was performed in both the training and testing groups, including receiver operating characteristic (ROC) curves, calibration plots and decision curve analysis (DCA). The potential value of MMP-associated genes was further verified using different IBD cohorts and clinical samples.

Results

Four datasets (GSE75214, GSE10616, GSE36807, and GSE9686) were included in the analysis. Both data integration methods indicated that the activation of the MMP-associated module was significantly elevated in UC. Two LASSO models based on continuous variable (Model_1) and binary variable (Model_2) MMP-associated genes were established to discriminate CD and UC. The results showed that Model_1 exhibited good discrimination in the training and testing groups. The calibration analysis and DCA showed that Model_1 exhibited good performance in the training group but failed in the testing group. Model_2 exhibited good discrimination, calibration and DCA results in the training and testing groups and exhibited greater diagnostic value. The effects of Model_1 and Model_2 were further verified in a new IBD cohort of GSE179285. The MMP genes exhibited high value as biomarkers for the discrimination of IBD patients using published cohort and immunohistochemistry (IHC) staining data. The MMP-associated gene levels were statistically significantly positively correlated with the levels of the differentially expressed cell types, indicating their potential value in differential diagnosis. The single-cell analysis confirmed that the expression of ANXA1 in UC was higher than that in CD.

Conclusion

MMP-associated modules are the main differential gene sets between CD and UC. The established Model_2 overcomes batch differences and has good clinical applicability. Subsequent in-depth research investigating how MMPs are involved in the development of different IBD subtypes is necessary.

Validating Cell Surface Proteases as Drug Targets for Cancer Therapy: What Do We Know, and Where Do We Go?

Cell surface proteases (also known as ectoproteases) are transmembrane and membrane-bound enzymes involved in various physiological and pathological processes. Several members, most notably dipeptidyl peptidase 4 (DPP4/CD26) and its related family member fibroblast activation protein (FAP), aminopeptidase N (APN/CD13), a disintegrin and metalloprotease 17 (ADAM17/TACE), and matrix metalloproteinases (MMPs) MMP2 and MMP9, are often overexpressed in cancers and have been associated with tumour dysfunction. With multifaceted actions, these ectoproteases have been validated as therapeutic targets for cancer. Numerous inhibitors have been developed to target these enzymes, attempting to control their enzymatic activity. Even though clinical trials with these compounds did not show the expected results in most cases, the field of ectoprotease inhibitors is growing. This review summarizes the current knowledge on this subject and highlights the recent development of more effective and selective drugs targeting ectoproteases among which small molecular weight inhibitors, peptide conjugates, prodrugs, or monoclonal antibodies (mAbs) and derivatives. These promising avenues have the potential to deliver novel therapeutic strategies in the treatment of cancers.

Matrix metalloproteinases in the pathogenesis of dengue viral disease: Involvement of immune system and newer therapeutic strategies

Globally, the burden due to dengue infection is increasing with a recent estimate of 96 million progressing to the disease every year. Dengue pathogenesis and the factors influencing it are not completely known. It is now widely speculated that there is an important role of matrix metalloproteinases (MMPs) in the initiation and progression of dengue pathogenesis; however, their exact roles are not fully understood. Overactivation of matrix metalloproteinases may contribute to the severity of dengue pathogenesis. Cytokines and various other mediators of inflammation interact with the vascular endothelium and matrix metalloproteinases may be one of the components among them. Extensive plasma leakage into tissue spaces may result in a shock. It is evident in the literature that MMP2 and MMP9 increase in dengue patients is correlated with the severity of the disease; however, the underlying mechanism is still unknown. Activation of innate cells and adaptive immune cells which include, B and T cells, macrophages or monocytes and dendritic cells also contribute to the dengue pathology. Newer therapeutic strategies include microRNAs, such as miR-134 (targets MMP3 and MMP1) and MicroRNA-320d, (targets MMP/TIMP proteolytic system). The use of antibodies-based therapeutics like (Andecaliximab; anti-matrix metalloproteinase-9 antibody) is also suggested against MMPs in dengue. In this review, we summarize some recent developments associated with the involvement of immune cells and their mediators associated with the matrix metalloproteinases mediated dengue pathogenesis. We highlight that, there is still very little knowledge about the MMPs in dengue pathogenesis which needs attention and extensive investigations.

Clinical, Endoscopic and Histological Outcomes in Induction of Moderate-to-Severe Ulcerative Colitis: A Systematic Review with Meta-Analysis

BACKGROUND AND AIMS

Interest in histology for ulcerative colitis [UC] has increased recently. This systematic review and meta-analysis aims to assess, for the first time, whether histological outcomes are more informative than endoscopic and clinical outcomes in distinguishing the impact of intervention over placebo in induction trials.

METHODS

MEDLINE, ScienceDirect and Cochrane Central Register of Controlled Trials were searched to identify randomized placebo-controlled trials [RCTs] enrolling moderate-to-severe UC patients. Studies were assessed using the Quality Assessment Tool for Studies with Diverse Designs. We analysed the pooled proportion of patients achieving clinical, endoscopic and histological remission and response after a pharmacological intervention and compared the results with those of placebo-treated patients by using a random-effects model.

RESULTS

From 889 identified records, 13 RCTs were included. The odds ratio [OR] for remission was higher in patients receiving intervention than in those under placebo for clinical (OR 2.13, 95% confidence interval [CI] 1.33-3.43), endoscopic [OR 1.46, 95% CI 0.19-11.18] and histological remission [OR 1.85, 95% CI 1.20-2.84]. Significant differences were observed for all response outcomes [clinical: OR 2.27, 95% CI 1.84-2.85; endoscopic: OR 2.16, 95% CI 1.51-3.10; histological: OR 3.63, 95% CI, 1.41-9.36]. No significant heterogeneity existed; no subgroup effects were found for duration of the induction or histological scale [p > 0.05]. Clinical and histological remission and endoscopic response were concordant in discriminating interventions from placebo.

CONCLUSION

Histological outcomes are informative in trials of moderate-to-severe UC. Further studies analysing histology at the end of induction are needed to confirm its relevance in distinguishing the efficacy of an intervention over placebo in comparison to clinical and endoscopic outcomes and to explore its prognostic value.

Metalloproteinases in Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD) are chronic inflammatory diseases of the gastrointestinal tract, encompassing two main disorders: Crohn's disease (CD) and ulcerative colitis (UC). In both these pathologies, excessive and local immune response against luminal antigens promotes a pathological process leading to various degrees of gut damage. Matrix metalloproteinases (MMPs) are a family of neutral proteases with the ability to degrade all components of extracellular matrix. In physiological conditions, MMPs are produced at very low level and generally in the latent form and are involved in the normal tissue turnover. Their function is inhibited by tissue inhibitors of metalloproteinases (TIMPs). However, in inflamed tissue of IBD patients, MMPs are produced in excess and/or the activity of TIMPs is not sufficient to block MMPs, thereby making a major contribution to the IBD-related mucosal degradation. In this review, we summarize the available evidence on the expression and role of MMPs in IBD.

Digestive Inflammation: Role of Proteolytic Dysregulation

Dysregulation of the proteolytic balance is often associated with diseases. Serine proteases and matrix metalloproteases are involved in a multitude of biological processes and notably in the inflammatory response. Within the framework of digestive inflammation, several studies have stressed the role of serine proteases and matrix metalloproteases (MMPs) as key actors in its pathogenesis and pointed to the unbalance between these proteases and their respective inhibitors. Substantial efforts have been made in developing new inhibitors, some of which have reached clinical trial phases, notwithstanding that unwanted side effects remain a major issue. However, studies on the proteolytic imbalance and inhibitors conception are directed toward host serine/MMPs proteases revealing a hitherto overlooked factor, the potential contribution of their bacterial counterpart. In this review, we highlight the role of proteolytic imbalance in human digestive inflammation focusing on serine proteases and MMPs and their respective inhibitors considering both host and bacterial origin.

Evaluating the optimum number of biopsies to assess histological inflammation in ulcerative colitis: a retrospective cohort study

BACKGROUND

The optimal ulcerative colitis biopsy protocol is unclear.

AIM

To evaluate the number of biopsies required to accurately assess microscopic disease activity in ulcerative colitis METHODS: Biopsies from patients with ≥4 rectosigmoid samples, and clinical and endoscopic data, were retrospectively obtained from a prospective biobank. Histology and endoscopic videos were read blindly. A 4-biopsy Robarts Histopathology Index (RHI) reference score, consisting of the worst item-level ratings from four biopsies, was compared to 1-, 2- and 3-biopsy estimates. Agreement was determined using bivariate errors-in-variable regression analysis (acceptance interval: ±8.25). Endoscopic activity and disease location subgroup analyses were also performed.

RESULTS

Forty-six patients had ≥4 rectosigmoid biopsies available (N = 287). The 2-biopsy (tolerance interval: -7.66, 4.79) and 3-biopsy (tolerance interval: -4.86, 3.46) RHI scores demonstrated acceptable agreement with 4-biopsy scores. One-biopsy scores demonstrated unacceptable agreement (tolerance interval: -13.99, 7.78). Mean RHI scores using the 2-, 3- and 4-biopsy approaches were similar (6.1 ± 9.6 P = 0.36; 6.8 ± 10.5, P = 0.7; 7.5 ± 11.2), whereas the 1-biopsy estimate was lower (4.4 ± 8.1, P = 0.06). Histological remission rates were identical for the 2-, 3- and 4-biopsy methods (65.2%, P = 1.0). Subgroup analysis demonstrated that three biopsies were required in patients with endoscopically active disease. Sampling additional colonic locations yielded lower histological remission rates compared to rectosigmoid sampling alone (33.3% vs 61.9%, P = 0.1).

CONCLUSIONS

A minimum of two - conservatively, three - biopsies are required to reliably assess disease activity in a single colonic segment using the RHI. Further studies are needed of endoscopically active patients and sampling locations. These results have implications for biopsy strategies in clinical trials and practice.

Generation of highly selective monoclonal antibodies inhibiting a recalcitrant protease using decoy designs

Matrix metalloproteinase-12 (MMP-12), also known as macrophage elastase, is a potent inflammatory mediator and therefore an important pharmacological target. Clinical trial failures of broad-spectrum compound MMP inhibitors suggested that specificity is the key for a successful therapy. To provide the required selectivity, monoclonal antibody (mAb)-based inhibitors are on the rise. However, poor production of active recombinant human MMP-12 catalytic domain (cdMMP-12) presented a technical hurdle for its inhibitory mAb development. We hypothesized that this problem could be solved by designing an expression-optimized cdMMP-12 mutant without structural disruptions at its reaction cleft and surrounding area, and thus isolated active-site inhibitory mAbs could maintain their binding and inhibition functions toward wild-type MMP-12. We combined three advances in the field-PROSS algorithm for cdMMP-12 mutant design, convex paratope antibody library construction, and functional selection for inhibitory mAbs. As a result, isolated Fab inhibitors showed nanomolar affinity and potency toward cdMMP-12 with high selectivity and high proteolytic stability. Particularly, Fab LH11 targeted the reaction cleft of wild-type cdMMP-12 with 75 nM binding K_D and 23 nM inhibition IC₅₀ . We expect that our methods can promote the development of mAbs inhibiting important proteases, many of which are recalcitrant to functional production.

Metalloproteinases and Their Inhibitors: Potential for the Development of New Therapeutics

The metalloproteinase (MP) family of zinc-dependent proteases, including matrix metalloproteinases (MMPs), a disintegrin and metalloproteases (ADAMs), and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTSs) plays a crucial role in the extracellular matrix (ECM) remodeling and degradation activities. A wide range of substrates of the MP family includes ECM components, chemokines, cell receptors, and growth factors. Metalloproteinases activities are tightly regulated by proteolytic activation and inhibition via their natural inhibitors, tissue inhibitors of metalloproteinases (TIMPs), and the imbalance of the activation and inhibition is responsible in progression or inhibition of several diseases, e.g., cancer, neurological disorders, and cardiovascular diseases. We provide an overview of the structure, function, and the multifaceted role of MMPs, ADAMs, and TIMPs in several diseases via their cellular functions such as proteolysis of other cell signaling factors, degradation and remodeling of the ECM, and other essential protease-independent interactions in the ECM. The significance of MP inhibitors targeting specific MMP or ADAMs with high selectivity is also discussed. Recent advances and techniques used in developing novel MP inhibitors and MP responsive drug delivery tools are also reviewed.

IL-18 immunoadjuvanted xenogeneic canine MMP-7 DNA vaccine overcomes immune tolerance and supresses the growth of murine mammary tumor

The development of the tumorigenesis and angiogenesis through proteolytic cleavage of extracellular matrix protein and basement membranes is promoted by Matrix metelloproteinases-7 (MMP-7). Consequently, MMP-7 is presumed as potential target for mammary cancer immunotherapy. However, MMP-7 is an endogenous tumor associated antigen (TAA); therefore, immunization is challenging. In current study, a potent anti-tumor immune response has been elicited through recombinant bivalent plasmid pVIVO2.IL18.cMMP7 which subside the highly metastatic 4 T1 cell line induced mammary tumors and efficiently negate the existing challenge of using MMP-7 as immunotherapeutic target. Balb/c mice were immunized with canine MMP-7 (cMMP-7) using interleukine-18 (IL-18), as an immunoadjuvant, to explore the potential of the combination regarding elicitation of a potent anti-tumor immune response. Mice vaccinated with pVIVO2.IL18.cMMP7 DNA plasmid reduced the tumor growth significantly along with augmentation of the immune response to fight against tumor antigen as depicted by substantial enrichment of CD4+ and CD8+ population in splenocytes, infiltration of immune system cells in tumor tissue and enhanced survival time of mice. Further, splenocyte supernatant examination of the cytokines revealed that Th1 cytokines (IFN-γ and IL-2) were remarkably up-regulated demonstrating the stimulation of cell-mediated immune response. Thus the current observations vividly portray that administration of xenogeneic MMP-7 DNA vaccine bypasses the tolerance barrier.

Current Endpoints of Clinical Trials in Ulcerative Colitis: Are They Valid?

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MMP (Matrix Metalloprotease)-9-Producing Monocytes Enable T Cells to Invade the Vessel Wall and Cause Vasculitis

RATIONALE

Giant cell arteritis (GCA)-a primary vasculitis of medium and large arteries-is associated with vessel wall damage, elastic membrane fragmentation, and vascular remodeling. Proteinases are believed to contribute to pathogenesis by degrading extracellular matrix and causing tissue injury.

OBJECTIVE

The MMP (matrix metalloproteinase)-9-a type IV collagenase-is produced in the vasculitic lesions of GCA. It is unknown which pathogenic processes are MMP-9 dependent.

METHODS AND RESULTS

The tissue transcriptome of GCA-affected temporal arteries contained high amounts of MMP-9 transcripts, and immunostaining for pro-MMP-9 localized the enzyme to wall-infiltrating macrophages. MMP-2 and MMP-9 transcripts were also abundant in monocytes and monocyte-derived macrophages from patients with GCA. Patient-derived monocytes outperformed healthy monocytes in passing through engineered basement membranes. GCA CD (cluster of differentiation) 4⁺ T cells required MMP-9-producing monocytes to penetrate through matrix built from type IV collagen. In vivo functions of MMP-9 were tested in a human artery-SCID (severe combined immunodeficiency) chimera model by blocking enzyme activity with a highly specific monoclonal antibody or by injecting rMMP-9 (recombinant MMP-9). Inhibiting MMP-9 activity profoundly suppressed vascular injury, decreased the density of inflammatory infiltrates ( P<0.001), reduced intramural neoangiogenesis ( P<0.001), and prevented intimal layer hyperplasia ( P<0.001). rMMP-9 amplified all domains of vasculitic activity, promoted assembly of T-cell infiltrates ( P<0.05), intensified formation of new microvessels ( P<0.001), and worsened intimal thickening ( P<0.001). Systemic delivery of N-acetyl-proline-glycine-proline-a matrikine produced by MMP-9-mediated gelatinolysis-had limited vasculitogenic effects.

CONCLUSIONS

In large vessel vasculitis, MMP-9 controls the access of monocytes and T cells to the vascular wall. T cells depend on MMP-9-producing monocytes to pass through collagen IV-containing basement membrane. Invasion of vasculitogenic T cells and monocytes, formation of neoangiogenic networks, and neointimal growth all require the enzymatic activity of MMP-9, identifying this protease as a potential therapeutic target to restore the immunoprivilege of the arterial wall in large vessel vasculitis.

The Rebirth of Matrix Metalloproteinase Inhibitors: Moving Beyond the Dogma

The pursuit of matrix metalloproteinase (MMP) inhibitors began in earnest over three decades ago. Initial clinical trials were disappointing, resulting in a negative view of MMPs as therapeutic targets. As a better understanding of MMP biology and inhibitor pharmacokinetic properties emerged, it became clear that initial MMP inhibitor clinical trials were held prematurely. Further complicating matters were problematic conclusions drawn from animal model studies. The most recent generation of MMP inhibitors have desirable selectivities and improved pharmacokinetics, resulting in improved toxicity profiles. Application of selective MMP inhibitors led to the conclusion that MMP-2, MMP-9, MMP-13, and MT1-MMP are not involved in musculoskeletal syndrome, a common side effect observed with broad spectrum MMP inhibitors. Specific activities within a single MMP can now be inhibited. Better definition of the roles of MMPs in immunological responses and inflammation will help inform clinic trials, and multiple studies indicate that modulating MMP activity can improve immunotherapy. There is a U.S. Food and Drug Administration (FDA)-approved MMP inhibitor for periodontal disease, and several MMP inhibitors are in clinic trials, targeting a variety of maladies including gastric cancer, diabetic foot ulcers, and multiple sclerosis. It is clearly time to move on from the dogma of viewing MMP inhibition as intractable.

Mechanisms of Action of Novel Drugs Targeting Angiogenesis-Promoting Matrix Metalloproteinases

Angiogenesis is facilitated by the proteolytic activities of members of the matrix metalloproteinase (MMP) family. More specifically, MMP-9 and MT1-MMP directly regulate angiogenesis, while several studies indicate a role for MMP-2 as well. The correlation of MMP activity to tumor angiogenesis has instigated numerous drug development programs. However, broad-based and Zn²⁺-chelating MMP inhibitors have fared poorly in the clinic. Selective MMP inhibition by antibodies, biologicals, and small molecules has utilized unique modes of action, such as (a) binding to protease secondary binding sites (exosites), (b) allosterically blocking the protease active site, or (c) preventing proMMP activation. Clinical trials have been undertaken with several of these inhibitors, while others are in advanced pre-clinical stages. The mechanistically non-traditional MMP inhibitors offer treatment strategies for tumor angiogenesis that avoid the off-target toxicities and lack of specificity that plagued Zn²⁺-chelating inhibitors.

Monoclonal Antibody Targeting the Matrix Metalloproteinase 9 Prevents and Reverses Paclitaxel-Induced Peripheral Neuropathy in Mice

Chemotherapy-induced peripheral neuropathy (CIPN) is a disabling condition accompanying several cancer drugs, including the front-line chemotherapeutic agent paclitaxel. Although CIPN can force dose reduction or even discontinuation of chemotherapy, affecting survival in cancer patients, there is no US Food and Drug Administration-approved treatment for CIPN. CIPN in mice is characterized by neuropathic pain (eg, mechanical allodynia) in association with oxidative stress and neuroinflammation in dorsal root ganglia (DRGs), as well as retraction of intraepidermal nerve fibers. Here, we report that paclitaxel-induced mechanical allodynia is associated with transcriptional increase in matrix metalloproteinase (MMP) 2 and 9 and decrease in metallopeptidase inhibitor 1 (TIMP1), a strong endogenous MMP9 inhibitor. Consistently, MMP9 protein levels are increased in DRG neurons in vivo and in vitro after paclitaxel treatment, and it is demonstrated, for the first time, that intrathecal injections of exogenous TIMP1 or a monoclonal antibody targeting MMP9 (MMP9 mAb) significantly prevented and reversed paclitaxel-induced mechanical allodynia in male and female mice. Analyses of DRG tissues showed that MMP9 mAb significantly decreased oxidative stress and neuroinflammatory mediators interleukin-6 and tumor necrosis factor α, as well as prevented paclitaxel-induced loss of intraepidermal nerve fibers. These findings suggest that MMP signaling plays a key role in paclitaxel-induced peripheral neuropathy, and MMP9 mAb may offer new therapeutic approaches for the treatment of CIPN. PERSPECTIVE: Chemotherapy-induced peripheral neuropathy (CIPN) remains ineffectively managed in cancer patients, potentially leading to the discontinuation of an otherwise life-saving treatment. Here, we demonstrate that a monoclonal antibody targeting MMP9 alleviates neuropathic pain and several mechanisms linked to CIPN. This study is particularly relevant, because a humanized MMP9 antibody is already in advanced clinical trials for the treatment of colitis and cancer, and it may be straightforwardly repurposed for the relief of CIPN.

Histologic Healing Rates of Medical Therapies for Ulcerative Colitis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

OBJECTIVES

Histologic remission is a potentially valuable means of assessing disease activity and treatment response in ulcerative colitis (UC). However, the efficacy of existing therapies to achieve this outcome is unclear. We performed a systematic review and meta-analysis of histologic outcomes in UC randomized controlled trials and examined the relationship between histologic and endoscopic outcomes.

METHODS

MEDLINE, EMBASE, CENTRAL, and the Cochrane IBD Register were searched for randomized controlled trials of aminosalicylates, corticosteroids, immunosuppressives, biologics, and small molecules. Histologic and endoscopic remission and response data were independently extracted and pooled using binomial-normal random-effect or fixed-effect models. Pooled efficacy estimates were calculated as risk ratios (RRs) using the Mantel-Haenszel method. Univariable and multivariable random-effect meta-regression models examined factors associated with histologic remission.

RESULTS

Seventy-four studies (68 induction and 7 maintenance) were identified. Topical aminosalicylate enemas [37.2%, 95% confidence interval (CI), 29.0-46.3] and suppositories (44.9%, 95% CI, 28.9-62.3) had the highest induction of histologic remission rates. Aminosalicylate enemas (RR = 4.14, 95% CI, 2.35-7.31), aminosalicylate suppositories (RR = 3.94, 95% CI, 1.26-12.32), and budesonide multimatrix (RR = 1.47, 95% CI 1.08-1.99) had higher histologic remission rates than placebo. Data were lacking for biologics and immunosuppressives. The pooled histologic remission rate for placebo in induction studies was 10.4% (95% CI, 7.1-15.2). Histologic and endoscopic remission correlated strongly (r = 0.66; 95% CI, 0.50-0.78). In multivariate analysis of placebo-arm data, less severe clinical disease activity and corticosteroid use were associated with higher histologic remission rates. Similarly, mild clinical disease activity was associated with higher histologic remission rates when active-arm data were analyzed.

CONCLUSIONS

Histologic remission rates for current UC treatments ranged from 15.0% to 44.9% according to drug class and patient population with the highest rates observed for topical aminosalicylates. Placebo remission rates were low with relatively narrow CIs. These data provide benchmarks to inform future trial design. Histologic remission is a potential treatment target in clinical practice.

Systematic review with meta-analysis: high prevalence and cost of continued aminosalicylate use in patients with ulcerative colitis escalated to immunosuppressive and biological therapies

BACKGROUND

Aminosalicylates are the most frequently prescribed treatment for ulcerative colitis (UC). In the absence of empirical evidence, clinicians are uncertain whether to continue aminosalicylates in patients with UC after escalating therapy.

AIMS

To quantify concomitant aminosalicylate use in UC randomised clinical trials (RCTs), identify factors associated with their use, and estimate treatment costs of concomitant aminosalicylate therapy.

METHODS

MEDLINE, Embase, and CENTRAL were searched from inception to 1 March 2017 for placebo-controlled RCTs of immunosuppressants, biologics, or oral small molecules in adults with UC. The proportion of patients prescribed concomitant aminosalicylates at trial entry was pooled using a random-effects model. Meta-regression was performed to assess trial-level factors associated with aminosalicylate use. Treatment costs were estimated using 2018 formulary data from five Canadian provinces.

RESULTS

Thirty-two trials were included (23 induction only, nine induction, and maintenance trials). The pooled proportion of patients co-prescribed aminosalicylates was 80.7% (95% CI 75.5%-85.1%), with considerable observed heterogeneity (I²  = 95%). In univariable meta-regression, aminosalicylate use was not associated with trial design, setting, year of publication, disease severity, disease duration, or drug class. The estimated direct annual treatment cost of concomitant aminosalicylates is ~$20 million for the Canadian UC population, assuming conservative estimates of UC prevalence, aminosalicylate use and dose, and the lowest cost formulation.

CONCLUSIONS

Approximately 80% of UC patients entering clinical trials of immunosuppressants, biologics, or oral small molecules continue to use aminosalicylates. An RCT is needed to inform the benefits and harms of continuing vs stopping aminosalicylates in patients escalating therapy.

Reducing proteolytic liability of a MMP-14 inhibitory antibody by site-saturation mutagenesis

Playing pivotal roles in tumor growth and metastasis, matrix metalloproteinase-14 (MMP-14) is an important cancer target. Potent inhibitory Fab 3A2 with therapy-desired high selectivity has been isolated from a synthetic antibody library carrying long CDR-H3s. However, like many standard mechanism protease inhibitors, Fab 3A2 can be cleaved by high concentrations of MMP-14 after extended incubation at acidic pH. Edman sequencing of generated 3A2 fragments indicated that cleavage occurred within its CDR-H3 between residues N100h (P1) and L100i (P1'). To improve proteolytic stability of 3A2, three positions adjacent to its cleavage site (P1, P1', and P3') were subjected to site-saturation mutagenesis (SSM). Mutations at P1' (L100i) resulted in loss of inhibition function, while screening of 3A2 Fab mutants at P1 (N100h) or P3' (A100k) positions identified four clones exhibiting improvements in both stability and inhibition potency. The majority of these mutants with improved stability were substitutions to either hydrophobic (Lue, Trp) or basic residues (Arg, Lys, His). Combinations of these beneficial mutations resulted in a double mutant N100hR/A100kR, which prolonged half-life twofold with an inhibition potency K_I of 6.6 nM. Enzyme kinetics and competitive ELISA suggested that N100hR/A100kR was a competitive inhibitor overlapping its binding epitope with that of nTIMP-2. This study demonstrated that site-directed mutagenesis at or near the cleavage position reduced proteolytic liability of standard mechanism protease inhibitors especially inhibitory antibodies.

Nanobodies as novel therapeutic agents in envenomation

BACKGROUND

An effective therapy against envenoming should be a priority in view of the high number scorpion stings and snakebites. Serum therapy is still widely applied to treat the envenomation victims; however this approach suffers from several shortcomings. The employment of monoclonal antibodies might be an outcome as these molecules are at the core of a variety of applications from protein structure determination to cancer treatment. The progress of activities in the twilight zone between genetic and antibody engineering have led to the development of a unique class of antibody fragments. These molecules possess several benefits and lack many possible disadvantages over classical antibodies. Within recombinant antibody formats, nanobodies or single domain antigen binding fragments derived from heavy chain only antibodies in camelids occupy a privileged position.

SCOPE OF REVIEW

In this paper we will briefly review the common methods of envenomation treatment and focus on details of various in vivo research activities that investigate the performance of recombinant, monoclonal nanobodies in venom neutralization.

MAJOR CONCLUSIONS

Nanobodies bind to their cognate target with high specificity and affinity, they can be produced in large quantities from microbial expression systems and are very robust even when challenged with harsh environmental conditions. Upon administering, they rapidly distribute throughout the body and seem to be well tolerated in humans posing low immunogenicity.

GENERAL SIGNIFICANCE

Scorpion and snake envenomation is a major issue in developing countries and nanobodies as a venom-neutralizing agent can be considered as a valuable and promising candidate in envenomation therapy.

A Phase 2, Randomized, Placebo-Controlled Study Evaluating Matrix Metalloproteinase-9 Inhibitor, Andecaliximab, in Patients With Moderately to Severely Active Crohn's Disease

BACKGROUND AND AIMS

Matrix metalloproteinase-9 [MMP9] is implicated in the pathogenesis of Crohn's disease and may serve as a potential biomarker. A phase 2 trial was conducted to examine the efficacy and safety of the anti-MMP9 antibody andecaliximab [GS-5745] in patients with moderately to severely active Crohn's disease.

METHODS

Patients were randomized 1:2:2:2 to receive subcutaneous injections of placebo weekly [QW], andecaliximab 150 mg every 2 weeks [Q2W], andecaliximab 150 mg QW, or andecaliximab 300 mg QW.The co-primary study efficacy endpoints were evaluation of a clinical response, defined as liquid or very soft stool frequency and abdominal pain composite [from Patient-Reported Outcome 2] score ≤ 8 at week 8, and an endoscopic response, defined as a ≥ 50% reduction from baseline in the Simple Endoscopic Score for Crohn's Disease, following 8 weeks of treatment.

RESULTS

A total of 187 participants were randomized to treatment; 53 participants were randomized to each andecaliximab treatment group and 28 participants were randomized to placebo. Proportions of patients receiving andecaliximab were not different from proportions of patients receiving placebo based on clinical and endoscopic response and Crohn's disease activity index-defined remission at week 8. Rates of adverse events were comparable among the andecaliximab and placebo groups.

CONCLUSIONS

Eight weeks of induction treatment with 150 mg andecaliximab Q2W, 150 mg andecaliximab QW, or 300 mg andecaliximab QW in patients with Crohn's disease did not induce a clinically meaningful symptomatic or endoscopic response. Andecaliximab was well tolerated.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT02405442.

Andecaliximab [Anti-matrix Metalloproteinase-9] Induction Therapy for Ulcerative Colitis: A Randomised, Double-Blind, Placebo-Controlled, Phase 2/3 Study in Patients With Moderate to Severe Disease

BACKGROUND AND AIMS

Matrix metalloproteinase-9 [MMP9] is implicated in the pathogenesis of ulcerative colitis [UC] via disruption of intestinal barrier integrity and function. A phase 2/3 combined trial was designed to examine the efficacy, safety, and pharmacokinetics of the anti-MMP9 antibody, andecaliximab [formerly GS-5745], in patients with moderately to severely active UC.

METHODS

Patients were randomised [1:1:1] to receive placebo, 150 mg andecaliximab every 2 weeks [Q2W], or 150 mg andecaliximab weekly [QW], via subcutaneous administration. The primary endpoint was endoscopy/bleeding/stool [EBS]-defined clinical remission [endoscopic subscore of 0 or 1, rectal bleeding subscore of 0, and at least a 1-point decrease from baseline in stool frequency to achieve a subscore of 0 or 1] at Week 8. The phase 2/3 trial met prespecified futility criteria and was terminated before completion. This study describes results from the 8-week induction phase.

RESULTS

Neither 150 mg andecaliximab Q2W or QW resulted in a significant increase vs placebo in the proportion of patients achieving EBS clinical remission at Week 8. Remission rates [95% confidence intervals] were 7.3% [2.0%-17.6%], 7.4% [2.1%-17.9%], and 1.8% [0.0%-9.6%] in the placebo, andecaliximab Q2W, and andecaliximab QW groups, respectively. Similarly, Mayo Clinic Score response, endoscopic response, and mucosal [histological] healing did not differ among groups. Rates of adverse events were comparable among andecaliximab and placebo.

CONCLUSIONS

Eight weeks of induction treatment with 150 mg andecaliximab in patients with UC did not induce clinical remission or response. Andecaliximab was well tolerated and pharmacokinetic properties were consistent with those previously reported.

The evolving immunotherapeutic landscape in advanced oesophagogastric cancer

Improvements in median overall survival in the advanced oesophagogastric (OG) setting have plateaued, underlining the need for improved therapeutic approaches in this patient population. Immunotherapeutics are inducing unexpected durable responses in an expanding list of advanced disease indications. Although OG cancers have traditionally been considered to be more challenging to treat with immunotherapy than some other malignancies because of their variable tumour mutational burden and relative scarcity of infiltrating T cells, immune checkpoint inhibitor (ICPI) trials conducted over the last few years suggest there is an important role for these treatments. ICPI efficacy may be demonstrated in specific molecular subtypes of OG cancer. This review outlines the improvements in defining predictive biomarkers of responsiveness to ICPIs. Increasingly, identification of an expanding list of ICPI resistance mechanisms will drive biomarker-directed research. In addition, the specific rationale to combine ICPIs with chemotherapies, radiotherapies, targeted therapies and other novel immunotherapeutic drugs will be discussed.

Systematic review with meta-analysis: endoscopic and histologic placebo rates in induction and maintenance trials of ulcerative colitis

BACKGROUND

Regulatory requirements for claims of mucosal healing in ulcerative colitis (UC) will require demonstration of both endoscopic and histologic healing. Quantifying these rates is essential for future drug development.

AIMS

To meta-analyse endoscopic and histologic placebo response and remission rates in UC randomised controlled trials (RCTs) and identify factors influencing these rates.

METHODS

MEDLINE, EMBASE and the Cochrane Library were searched from inception to March 2017 for placebo-controlled trials of pharmacological interventions for UC. Endoscopic and histologic placebo rates were pooled by random effects. Mixed effects univariable and multivariable meta-regression was used to evaluate the influence of patient, intervention and trial-related study-level covariates on these rates.

RESULTS

Fifty-six induction (placebo n = 4171) and 8 maintenance trials (placebo n = 1011) were included. Pooled placebo endoscopic remission and response rates for induction trials were 23% [95 confidence interval (CI) 19-28%] and 35% [95% CI 27-42%] respectively, and 20% [95% CI 16-24%] for maintenance of remission. The pooled histologic placebo remission rate was 14% [95% CI 8-22%] for induction trials. High heterogeneity was observed for all outcomes (I² 56.2%-88.3%). On multivariable meta-regression, central endoscopy reading was associated with significantly lower endoscopic placebo remission rates (16% vs 25%; OR = 0.52, [95% CI 0.29-0.92], P = 0.03). On univariable meta-regression, higher histologic placebo remission was associated with concomitant corticosteroids (OR = 1.17 [95% CI 1.08-1.26], P < 0.0001, per 10% increase in corticosteroid use).

CONCLUSIONS

Placebo endoscopic and histologic rates range from 14% to 35% in UC RCTs but are highly heterogeneous. Outcome standardisation may reduce heterogeneity and is needed in this field.

Biomolecular basis of matrix metallo proteinase-9 activity

Matrix metalloproteinases (MMPs) are structurally related endopeptidases. They are also known as metzincins due to their interaction with zinc ion of the conserved methionine (Met) at the active site. MMPs play an important role in physiological and signaling processes of wound healing, bone resorption and angiogenesis. The structure of MMPs consists of signal peptide, propeptide, catalytic domain, hinge region and hemopexin-like domain. MMP-9 shares high structural and functional similarities with MMP-2, therefore designing selective MMP-9 inhibitors (MMPIs) is challenging. The selectivity can be achieved by targeting S2 subsite of MMP-9 that is having difference with MMP-2. Further, targeting its exosite and protein disulfide isomerase may also provide selective MMPIs. The review highlights the molecular features and basis of MMP-9 enzyme action. The MMPIs reported in the recent years have also been included.

Heterogeneity in Definitions of Endpoints for Clinical Trials of Ulcerative Colitis: A Systematic Review for Development of a Core Outcome Set

BACKGROUND & AIMS

Advances in development of therapeutic agents for ulcerative colitis (UC) have been paralleled by innovations in trial design. It would be useful to identify a core outcome set, to standardize outcome definitions for efficacy and safety in clinical trials. We performed a systematic review of efficacy and safety outcomes reported in placebo-controlled randomized controlled trials of patients with UC.

METHODS

We searched MEDLINE, EMBASE, and the Cochrane Library from inception through March 1, 2017, for placebo-controlled randomized controlled trials of adult patients with UC treated with aminosalicylates, immunosuppressants, corticosteroids, biologics, and oral small molecules. We collected information on efficacy and safety outcomes, definitions, and measurement tools, stratified by decade of publication.

RESULTS

We analyzed data from 83 randomized controlled trials (68 induction and 15 maintenance) comprising 17,737 patients. Clinical or composite-clinical efficacy outcomes were reported in all trials; the UC Disease Activity Index and Mayo Clinic Score were frequently used to determine clinical response or remission. We found substantial variation in definitions of clinical or composite-clinical endpoints, with more than 50 definitions of response or remission. Endoscopic factors, histologic features, and fecal or serum biomarkers were used to determine outcomes in 83.1% (69 of 83), 24.1% (20 of 83), and 24.1% (20 of 83) of trials, respectively. A greater proportion of trials published after 2007 reported objective outcomes (96.5% endoscopic, 26.3% histologic, and 36.8% biomarker outcomes), but no standardized definitions of histologic or biomarker endpoints were found. Patient-reported efficacy and quality-of-life outcomes were described in 25 trials (30.1%) and safety outcomes were reported in 77 trials (92.8%).

CONCLUSION

In a systematic review, we found that despite recent advances in clinical trials methods, there is a great deal of variation in definitions of endpoints, including response and remission, in randomized controlled trials of patients with UC. Researchers should identify a core set of outcomes to standardize efficacy and safety reporting in UC clinical trials.

Monoclonal antibodies against metzincin targets

The metzincin clan of metalloproteinases includes the MMP, disintegrin and metalloproteinase (ADAM) and ADAM with thrombospondin motifs families, which cleave extracellular targets in a wide range of (patho)physiological processes. Antibodies constitute a powerful tool to modulate the activity of these enzymes for both therapeutic and research purposes. In this review, we give an overview of monoclonal antibodies (mAbs) that have been tested in preclinical disease models, human trials and important studies of metzincin structure and function. Initial attempts to develop therapeutic small molecule inhibitors against MMPs were hampered by structural similarities between metzincin active sites and, consequently, off-target effects. Therefore, more recently, mAbs have been developed that do not bind to the active site but bind to surface-exposed loops that are poorly conserved in closely related family members. Inhibition of protease activity by these mAbs occurs through a variety of mechanisms, including (i) barring access to the active site, (ii) disruption of exosite binding, and (iii) prevention of protease activation. These different modes of inhibition are discussed in the context of the antibodies' potency, selectivity and, importantly, the effects in models of disease and clinical trials. In addition, various innovative strategies that were used to generate anti-metzincin mAbs are discussed. LINKED ARTICLES: This article is part of a themed section on Translating the Matrix. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.1/issuetoc.

Generation of Highly Selective MMP Antibody Inhibitors

Inhibiting individual MMPs of biomedical importance with high selectivity is critical for both fundamental research and therapy development. Here we describe the methods for discovery of inhibitory monoclonal antibodies from synthetic human antibody phage display libraries carrying convex paratopes encoded by long complementarity-determining region (CDR)-H3 segments. We demonstrate the application of this technique for isolation of highly specific and potent antibody inhibitors of human MMP-14.

Phase 1b Study of the Safety, Pharmacokinetics, and Disease-related Outcomes of the Matrix Metalloproteinase-9 Inhibitor Andecaliximab in Patients With Rheumatoid Arthritis

PURPOSE

Andecaliximab (GS-5745) is a highly selective monoclonal antibody against matrix metalloproteinase-9 (MMP9), a proteolytic enzyme implicated in the pathogenesis of rheumatoid arthritis (RA). This study assessed the safety and pharmacokinetic (PK) parameters of andecaliximab in patients with RA and evaluated the effects of andecaliximab treatment on exploratory disease biomarkers.

METHODS

In this double-blind, Phase 1b trial, patients with active RA were randomized (4:1) to receive 400-mg andecaliximab or placebo every 2 weeks for a total of 3 intravenous infusions. The primary and secondary end points were safety and the PK parameters of andecaliximab, respectively. Data were summarized by using descriptive statistics.

FINDINGS

A total of 18 patients were randomized; 15 received andecaliximab (participants with confirmed RA diagnosis without current administration of a biologic DMARD a biologic DMARD (disease-modifying antirheumatic drug), aged 18 to 70 years old, weighing >45 to <120 kg). No deaths, serious adverse events, or study discontinuations occurred. All reported adverse events were grade 1 or grade 2 in severity. Mean plasma andecaliximab exposure was 587 d · µg/mL and 878 d · µg/mL at days 1 and 29, respectively, suggesting moderate accumulation. The median terminal t_1/2 was 5.65 days; mean volume of distribution at steady state was 4560 mL. Mean MMP9 coverage (the percentage of total plasma MMP9 bound by therapeutic antibody) was maintained at ~80% after the first administration of andecaliximab.

IMPLICATIONS

Andecaliximab administered as 3 infusions over 29 days was generally safe and well tolerated in patients with RA. The majority of total plasma MMP9 was bound by andecaliximab after the first administration. Clinical studies of increased treatment duration in larger patient cohorts are warranted. ClinicalTrials.gov identifier: NCT02176876. Registered on 25 June 2014.

Clinical Implications of Compounds Designed to Inhibit ECM-Modifying Metalloproteinases

Remodeling of the extracellular matrix (ECM) is crucial in development and homeostasis, but also has a significant role in disease progression. Two metalloproteinase families, the matrix metalloproteinases (MMPs) and a disintegrin and metalloproteases (ADAMs), participate in the remodeling of the ECM, either directly or through the liberation of growth factors and cell surface receptors. The correlation of MMP and ADAM activity to a variety of diseases has instigated numerous drug development programs. However, broad-based and Zn²⁺ -chelating MMP and ADAM inhibitors have fared poorly in the clinic. Selective MMP and ADAM inhibitors have been described recently based on (a) antibodies or antibody fragments or (b) small molecules designed to take advantage of protease secondary binding sites (exosites) or allosteric sites. Clinical trials have been undertaken with several of these inhibitors, while others are in advanced pre-clinical stages.

Placebo response and remission rates in randomised trials of induction and maintenance therapy for ulcerative colitis

BACKGROUND

It is important to minimize placebo rates in randomised controlled trials (RCTs) to efficiently detect treatment differences between interventions. Historically, high placebo rates have been observed in clinical trials of ulcerative colitis (UC). A better understanding of factors influencing placebo rates may lead to more informed clinical trial design.

OBJECTIVES

A systematic review and meta-analysis was conducted to evaluate placebo response and remission rates in RCTs evaluating UC treatments in adult patients.

SEARCH METHODS

Electronic databases (i.e. MEDLINE, EMBASE, and CENTRAL) were searched from inception to 1 March 2017 with no language restrictions applied. Reference lists and conference proceedings of major gastroenterology meetings were also handsearched to identify additional studies.

SELECTION CRITERIA

Placebo-controlled RCTs of adult patients with UC treated with corticosteroids, aminosalicylates, immunosuppressives or biologics were eligible, provided enrolment and outcome assessment was conducted using the Ulcerative Colitis Disease Activity Index (UCDAI) or the Mayo Clinic Score. The minimum trial duration was two weeks for induction trials and four months maintenance trials.

DATA COLLECTION AND ANALYSIS

Pairs of authors independently determined study eligibility and extracted data with any disagreements resolved through consensus. Outcomes of interest included the proportion of patients with clinical response and remission. Trial characteristics such as the design, participant demographics and disease history, interventions, and enrolment and assessment criteria were also recorded. The methodological quality of the included studies was evaluated using the Cochrane risk of bias tool. Pooled placebo response and remission rates and 95% confidence intervals (95% CI) were calculated using a binomial normal model for proportions. Induction of remission and maintenance studies were pooled separately. The impact of study-level characteristics on placebo response and remission rates was investigated using mixed-effects meta-regression analyses with logits of event rates as the outcome variables. An assessment of pooled placebo rates over time was conducted using a cumulative meta-analysis based on date of publication. Publication bias was examined using funnel plots.

MAIN RESULTS

The screening process identified 61 included studies which encompass 58 induction phases (5111 patients randomised to placebo) and 12 maintenance phases (1579 patients randomised to placebo). For induction trials, the pooled estimate of placebo response was 33% (95% CI 30% to 36%) while the pooled estimate of placebo remission was 12% (95% CI 9% to 15%). For maintenance trials, the pooled estimate of placebo response was 23% (95% CI 19% to 28%) while the pooled estimate of placebo remission was 17% (95% CI 10% to 27%).Studies enrolling patients with more active disease confirmed objectively by endoscopy were associated with significantly lower placebo remission and response rates than trials enrolling patients with less active disease (27% versus 4%, OR 2.60, 95% CI 1.25 to 5.42, P = 0.01 for UCDAI endoscopy sub score ≥1 versus ≥ 2 for remission; and 27% versus 4%, OR 1.70, 95% CI 1.02 to 2.82, P = 0.02 for UCDAI endoscopy sub score greater than or equal to one versus greater than or equal to two for response). With respect to drug class, the lowest placebo response and remission rates were observed in trials evaluating corticosteroids (23%; 95% CI 19 to 29%, and 5%; 95% CI 2 to 11%, respectively). Trials of biologics had the highest placebo response rate (35%; 95% CI 30 to 41%), while trials evaluating aminosalicylates had the highest placebo remission rate (18%; 95% CI 12 to 24%). Disease duration of greater than five years prior to enrolment was associated with a significantly lower placebo response rate compared to disease duration of less than or equal to five years (29% versus 47%, respectively; OR 0.54, 95% CI 0.32 to 0.92, P = 0.02). The requirement of a minimum rectal bleeding score for study eligibility was associated with an increased placebo response rate compared to studies that did not use rectal bleeding for trial eligibility (37% versus 32%, respectively; OR 1.70, 95% CI 1.02 to 2.82, P = 0.02). Finally, the time point of primary outcome assessment was found to be significantly associated with placebo remission rates such that every one week increment in endpoint assessment was associated with a 6% increase in the placebo remission rate (OR 1.06, 95% CI 1.02 to 1.10, P = 0.01).Cumulative meta-analysis indicated a consistent increase in the placebo response rate from 1987 to 2007 (from 13% to 33%), although rates have remained constant from 2008 to 2015 (32% to 34%). Similarly, placebo remission rates increased from 1987 to 2007 (5% to 14%) but have remained constant from 2008 to 2015 (12 to 14%). On meta-regression, there were no statistically significant differences between the 1987-2007 and 2008-2015 point estimates for both response (P = 0.81) and remission (P = 0.32).

AUTHORS' CONCLUSIONS

Placebo response and remission rates vary according to endoscopic disease severity and rectal bleeding score at trial entry, class of agent, disease duration, and the time point at which the primary outcome was measured. These observations have important implications for the design and conduct of future clinical trials in UC and will help researchers design trials, determine required sample sizes and also provide useful information about trial design features which should be considered when planning new trials.

Inhibition of gelatinase B/MMP-9 does not attenuate colitis in murine models of inflammatory bowel disease

One third of patients with inflammatory bowel disease (IBD) inadequately respond to anti-TNF treatment and preclinical data suggest that matrix metalloproteinase-9 (MMP-9) is a novel therapeutic target. Here we show that IBD clinical and histopathological parameters found in wild type mice challenged with three different models of colitis, acute and chronic dextran sodium sulphate (DSS), and acute 2,4,6-trinitrobenzenesulfonic acid-induced colitis are not attenuated in MMP-9 knockout mice. We find similar colonic gene expression profiles in wild type and MMP-9 knockout mice in control and acute DSS conditions with the exception of eleven genes involved in antimicrobial response during colitis. Parameters of chronic colitis are similar in wild type and MMP-9 knockout mice. Pharmacological inhibition of MMP-9 with bio-active peptides does not improve DSS colitis. We suggest that MMP-9 upregulation is a consequence rather than a cause of intestinal inflammation and we question whether MMP-9 represents a disease target in IBD.

Metalloproteinase-9 has been suggested as therapeutic target to treat inflammatory bowel disease. Here de Bruyn et al. show that genetic and pharmacological inhibition of metalloproteinase-9 does not ameliorate inflammation and fibrosis in mice challenged with acute and chronic colitis protocols.

Second Generation Triple-Helical Peptide Inhibitors of Matrix Metalloproteinases

The design of selective matrix metalloproteinase (MMP) inhibitors that also possess favorable solubility properties has proved to be especially challenging. A prior approach using collagen-model templates combined with transition state analogs produced a first generation of triple-helical peptide inhibitors (THPIs) that were effective in vitro against discrete members of the MMP family. These THPI constructs were also highly water-soluble. The present study sought improvements in the first generation THPIs by enhancing thermal stability and selectivity. A THPI selective for MMP-2 and MMP-9 was redesigned to incorporate non-native amino acids (Flp and mep), resulting in an increase of 18 °C in thermal stability. This THPI was effective in vivo in a mouse model of multiple sclerosis, reducing clinical severity and weight loss. Two other THPIs were developed to be more selective within the collagenolytic members of the MMP family. One of these THPIs was serendipitously more effective against MMP-8 than MT1-MMP and was utilized successfully in a mouse model of sepsis. The THPI targeting MMP-8 minimized lung damage, increased production of the anti-inflammatory cytokine IL-10, and vastly improved mouse survival.

Neutrophils in ulcerative colitis: a review of selected biomarkers and their potential therapeutic implications

OBJECTIVES

This review article describes the role of neutrophils in mucosal injury and the resulting crypt abscesses characteristic of ulcerative colitis. We also review selected biomarkers for monitoring neutrophil presence and activity in the mucosa as well as their potential as therapeutic targets.

MATERIAL

We have collated and selectively reviewed data on the most prominent well-established and emerging neutrophil-related biomarkers and potential therapeutic targets (calprotectin, lactoferrin, CXCR1, CXCR2, MMP-9, NGAL, elafin, HNE, pANCAs, MPO, CD16, CD177, CD64, HNPs, SLPI and PTX3) in ulcerative colitis.

RESULTS

Systemic and intestinal neutrophil activity increases substantially in active ulcerative colitis, driving tissue damage and extra-intestinal manifestations. Calprotectin is a robust neutrophil and disease biomarker, and a few neutrophil-related targets are being clinically explored as therapeutic targets.

CONCLUSION

We propose that targeting neutrophils and their inflammatory mediators per se is an opportunity that should be explored to identify new effective medical therapies. The overall clinical goal for neutrophil-targeted therapy will be to modulate, but not completely silence, neutrophil activity, thereby abolishing the destructive inflammation with associated acute and chronic tissue damage without compromising host-defense.

The Dual Role of Neutrophils in Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD), including Crohn’s disease and ulcerative colitis, are characterised by aberrant immunological responses leading to chronic inflammation without tissue regeneration. These two diseases are considered distinct entities, and there is some evidence that neutrophil behaviour, above all other aspects of immunity, clearly separate them. Neutrophils are the first immune cells recruited to the site of inflammation, and their action is crucial to limit invasion by microorganisms. Furthermore, they play an essential role in proper resolution of inflammation. When these processes are not tightly regulated, they can trigger positive feedback amplification loops that promote neutrophil activation, leading to significant tissue damage and evolution toward chronic disease. Defective chemotaxis, as observed in Crohn’s disease, can also contribute to the disease through impaired microbe elimination. In addition, through NET production, neutrophils may be involved in thrombo-embolic events frequently observed in IBD patients. While the role of neutrophils has been studied in different animal models of IBD for many years, their contribution to the pathogenesis of IBD remains poorly understood, and no molecules targeting neutrophils are used and validated for the treatment of these pathologies. Therefore, it is crucial to improve our understanding of their mode of action in these particular conditions in order to provide new therapeutic avenues for IBD.

Active-site MMP-selective antibody inhibitors discovered from convex paratope synthetic libraries

Proteases are frequent pharmacological targets, and their inhibitors are valuable drugs in multiple pathologies. The catalytic mechanism and the active-site fold, however, are largely conserved among the protease classes, making the development of the selective inhibitors exceedingly challenging. In our departure from the conventional strategies, we reviewed the structure of known camelid inhibitory antibodies, which block enzyme activities via their unusually long, convex-shaped paratopes. We synthesized the human Fab antibody library (over 1.25 × 10⁹ individual variants) that carried the extended, 23- to 27-residue, complementarity-determining region (CDR)-H3 segments. As a proof of principle, we used the catalytic domain of matrix metalloproteinase-14 (MMP-14), a promalignant protease and a drug target in cancer, as bait. In our screens, we identified 20 binders, of which 14 performed as potent and selective inhibitors of MMP-14 rather than as broad-specificity antagonists. Specifically, Fab 3A2 bound to MMP-14 in the vicinity of the active pocket with a high 4.8 nM affinity and was similarly efficient (9.7 nM) in inhibiting the protease cleavage activity. We suggest that the convex paratope antibody libraries described here could be readily generalized to facilitate the design of the antibody inhibitors to many additional enzymes.

Anti-MMP-9 Antibody: A Promising Therapeutic Strategy for Treatment of Inflammatory Bowel Disease Complications with Fibrosis

BACKGROUND

Despite medical treatments or surgical options, more than one-third of patients with Crohn's disease suffer from recurring fistulae. Matrix metalloprotease 9 (MMP-9), a type IV collagenase that cleaves components of the extracellular matrix leading to tissue remodeling, is upregulated in crypt abscesses and around fistulae suggesting an important role for this enzyme in fistula formation. Our aims were (1) to correlate serum levels of MMP-9 degradation products in patients with CD with the presence of fistulae and (2) to investigate the impact of selective MMP-9 inhibition in a mouse model of intestinal fibrosis.

METHODS

Serum MMP-9 degradation products were quantified in subjects affected with nonstricturing and nonpenetrating CD (n = 50), stricturing CD (n = 41), penetrating CD (n = 22), CD with perianal fistula (n = 29), and healthy controls (n = 10). Therapeutic efficacy of anti-MMP-9 monoclonal antibodies was assessed in a heterotopic xenograft model of intestinal fibrosis.

RESULTS

C3M, an MMP-9 degradation product of collagen III, demonstrated the highest serum levels in patients with penetrating CD and differentiated penetrating CD from other CD subgroups and healthy controls, P = 0.0005. Anti-MMP-9 treatments reduced collagen deposition and hydroxyproline content in day-14 intestinal grafts indicating reduced fibrosis.

CONCLUSIONS

The serologic biomarker C3M can discriminate penetrating CD from other CD subgroups and could serve as marker for the development of penetrating CD. Anti-MMP-9 antibody has therapeutic potential to prevent intestinal fibrosis in CD complications.