Use of mycophenolate mofetil in inflammatory bowel disease

Synthesis and Biological Evaluation of Novel Anti-leukemia Proteolysis-Targeting Chimeras in Degradating Inosine Monophosphate Dehydrogenase

Background

Proteolysis-targeting chimera (PROTAC) is a bifunctional molecule comprising a ligand to recognize the targeted protein to be degraded.

Objectives

To use the advantages of the PROTAC technique, we have synthesized novel compounds to degrade inosine monophosphate dehydrogenase (IMPDH) by the proteasome system.

Methods

We describe the synthesis of new PROTACs based on a combination of mycophenolic acid (MPA) as the potent IMPDH inhibitor and pomalidomide as a ligand of E3 ubiquitin ligase via linkers formed from Cu(I)-catalyzed cycloaddition reaction.

Results

All synthesized compounds were investigated against Jurkat cells as acute T-cell leukemia and were potent apoptosis inducers at 50 nM.

Conclusion

The effect of compound 2 in 0.05 μM on IMPDH degradation can be almost prevented by competition with bortezomib as the proteasome inhibitor at 0.1 and 0.5 μM.

Real-world use of mycophenolate mofetil in inflammatory bowel disease: Results from the ENEIDA registry

BACKGROUND

Studies to evaluate the use of mycophenolate mofetil (MMF) in inflammatory bowel disease (IBD) are limited after the appearance of biological treatments.

AIMS

Our primary objective was to evaluate the effectiveness and safety of MMF in IBD.

METHODS

IBD patients who had received MMF were retrieved from the ENEIDA registry. Clinical activity as per the Harvey-Bradshaw Index (HBI), partial Mayo score (pMS), physician global assessment (PGA) and C-reactive protein (CRP) were reviewed at baseline, at 3 and 6 months, and at final follow-up. Adverse events and causes of treatment discontinuation were documented.

RESULTS

A total of 83 patients were included (66 Crohn's disease, 17 ulcerative colitis), 90% of whom had previously received other immunosuppressants. In 61% of patients systemic steroids were used at initiation of MMF, and in 27.3% biological agents were co-administered with MMF. Overall clinical effectiveness was observed in 64.7% of the population. At the end of treatment, 45.6% and 19.1% of subjects showed remission and clinical response, respectively. MMF treatment was maintained for a median of 28.9 months (IQR: 20.4-37.5).

CONCLUSION

Our study suggests, in the largest cohort to date, that MMF may be an effective alternative to thiopurines and methotrexate in IBD.

Immunomodulators: still having a role?

Immunomodulators, particularly the thiopurines and to a lesser extent methotrexate, were standard of care for inflammatory bowel diseases, including Crohn’s disease and ulcerative colitis, for >40 years. While there has been a renaissance in available therapies with the advent of biologics and small molecules, an impetus remains for the ongoing use of thiopurines and methotrexate. This is particularly true for the maintenance of remission and when used in combination therapy with infliximab to suppress anti-biologic antibodies. This article summarizes the data behind immunomodulator use in Crohn’s disease, focusing on the beneficial role these drugs still have while acknowledging their clinical limitations.

De Novo Inflammatory Bowel Disease Rarely Occurs During Posttransplant Immunosuppression

OBJECTIVES

De novo chronic idiopathic inflammatory bowel disease (CIIBD) is reported to occur at higher rates in posttransplant patients than that of the general population. The previous reports, however, included patients with primary sclerosing cholangitis (PSC), a known association with CIIBD. Hence, we investigated how often posttransplant de novo CIIBD occurs in the absence of PSC.

METHODS

We identified 185 posttransplant adults without a history of PSC or CIIBD, who had undergone colonoscopy between July 2013 and June 2020. Biopsies were reviewed and clinical data were gathered.

RESULTS

CIIBD-like colitis accounted for 1.1% (2/185) of our cohort. The 2 affected patients were already taking multiple immunosuppressive therapies. They were initially placed on standard CIIBD maintenance therapy, but then required escalation therapy. One patient had persistent active colitis despite escalation therapy, while the other subsequently had resolution of symptoms and developed quiescent disease.

CONCLUSIONS

The incidence of CIIBD-like colitis in our study population was lower than what has been previously described. Both patients had a poor response to standard CIIBD therapy, raising the question whether their diagnosis is truly de novo CIIBD or another immunologic process.

Chemoproteomics-Enabled De Novo Discovery of Photoswitchable Carboxylesterase Inhibitors for Optically Controlled Drug Metabolism

Herein, we report arylazopyrazole ureas and sulfones as a novel class of photoswitchable serine hydrolase inhibitors and present a chemoproteomic platform for rapid discovery of optically controlled serine hydrolase targets in complex proteomes. Specifically, we identify highly potent and selective photoswitchable inhibitors of the drug-metabolizing enzymes carboxylesterases 1 and 2 and demonstrate their pharmacological application by optically controlling the metabolism of the immunosuppressant drug mycophenolate mofetil. Collectively, this proof-of-concept study provides a first example of photopharmacological tools to optically control drug metabolism by modulating the activity of a metabolizing enzyme. Our arylazopyrazole ureas and sulfones offer synthetically accessible scaffolds that can be expanded to identify specific photoswitchable inhibitors for other serine hydrolases, including lipases, peptidases, and proteases. Our chemoproteomic platform can be applied to other photoswitches and scaffolds to achieve optical control over diverse protein classes.

Gastrointestinal complications after kidney transplantation

Gastrointestinal complications are common after renal transplantation, and they have a wide clinical spectrum, varying from diarrhoea to post-transplant inflammatory bowel disease (IBD). Chronic immunosuppression may increase the risk of post-transplant infection and medication-related injury and may also be responsible for IBD in kidney transplant re-cipients despite immunosuppression. Differentiating the various forms of post-transplant colitis is challenging, since most have similar clinical and histological features. Drug-related colitis are the most frequently encountered colitis after kidney transplantation, particularly those related to the chronic use of mycophenolate mofetil, while de novo IBDs are quite rare. This review will explore colitis after kidney transplantation, with a particular focus on different clinical and histological features, attempting to clearly identify the right treatment, thereby improving the final outcome of patients.

Secondary causes of inflammatory bowel diseases

Inflammatory bowel diseases (IBD), conventionally consist of Crohn’s disease (CD) and ulcerative colitis. They occur in individuals with high risk genotype for the disease in the setting of appropriate environmental factors. The pathogenesis of IBD involves a dysregulated autoimmune response to gut dysbiosis, which in turn is triggered due to exposure to various inciting environmental factors. But there is no clearly defined etiology of IBD and this type of disease is termed as “idiopathic IBD”, “classic IBD”, or “primary IBD”. We reviewed the current medical literature and found that certain etiological factors may be responsible for the development of IBD or IBD-like conditions, and we consider this form of de novo IBD as “secondary IBD”. Currently known factors that are potentially responsible for giving rise to secondary IBD are medications; bowel altering surgeries and transplantation of organs, stem cells or fecal microbiome. Medications associated with the development of secondary IBD include; immunomodulators, anti-tumor necrosis factor alpha agents, anti-interleukin agents, interferons, immune stimulating agents and checkpoint inhibitors. Colectomy can in some cases give rise to de novo CD, pouchitis of the ileal pouch, or postcolectomy enteritis syndrome. After solid organ transplantation or hematopoietic stem cell transplantation, the recipient may develop de novo IBD or IBD flare. Fecal microbiota transplantation has been widely used to treat patients suffering from recurrent Clostridium difficile infection but can also causes IBD flares.

Management of psoriasis in patients with inflammatory bowel disease: From the Medical Board of the National Psoriasis Foundation

BACKGROUND

There is a significant association between psoriasis and inflammatory bowel disease (IBD). Many treatments for psoriasis and psoriatic arthritis are also used for IBD.

OBJECTIVE

To assess therapeutic options for patients with psoriasis and concurrent IBD.

METHODS

A systematic literature search was performed for clinical studies of biologic and systemic psoriasis medications in psoriasis, psoriatic arthritis, ulcerative colitis, and Crohn's disease, for the period from January 1, 1947, to February 14, 2017. Randomized, controlled, double-blinded studies were selected if available. If not, the next highest level of available evidence was selected.

RESULTS

Of the 2282 articles identified, 132 were selected. Infliximab and adalimumab have demonstrated efficacy in psoriasis, psoriatic arthritis, ulcerative; colitis, and Crohn's disease. Ustekinumab has demonstrated efficacy in psoriasis, psoriatic arthritis, and Crohn's disease. Certolizumab has demonstrated efficacy in psoriatic arthritis and Crohn's disease. Etanercept, secukinumab, brodalumab, and ixekizumab have demonstrated efficacy in psoriasis and psoriatic arthritis but may exacerbate or induce IBD. Guselkumab has demonstrated efficacy in psoriasis.

LIMITATIONS

There are no known clinical trials of treatment specifically for concurrent psoriasis and IBD.

CONCLUSIONS

Infliximab and adalimumab have demonstrated efficacy in psoriasis, psoriatic arthritis, ulcerative colitis, and Crohn's disease; other agents have demonstrated efficacy for some, but not all, of these indications.

Mycophenolate mofetil is a valid option in patients with inflammatory bowel disease resistant to TNF-α inhibitors and conventional immunosuppressants

BACKGROUND

Few studies investigated the role of mycophenolate mofetil in inflammatory bowel disease, and none of them had specifically focused on patients with previous multiple intolerances and/or nonresponses to conventional immunosuppressants and biologics.

AIMS

To evaluate clinical benefit and tolerability profile of mycophenolate mofetil in patients with inflammatory bowel disease and limited treatment options.

METHODS

All consecutive patients with previous multiple intolerances and/or nonresponses to immunosuppressants and biologics who started an off-label treatment with mycophenolate mofetil from January 2014 to February 2016 were entered in a prospectively maintained database.

RESULTS

Twenty-four patients were included. Four weeks after initiation of mycophenolate mofetil therapy, a steroid-free remission was achieved in 4 patients (16.7%), while a clinical response in 13 (54.1%). At the end of follow-up, 12 patients (50.0%) remained on mycophenolate mofetil. Six achieved and maintained steroid-free remission throughout the study period (25.0%), and a further 6 patients (25.0%) achieved a clinical response with complete discontinuation of steroids. Twelve patients (50.0%) were considered as treatment failure, and five of them underwent surgery.

CONCLUSIONS

This is the first experience reporting a clinical benefit and tolerability of mycophenolate mofetil in patients with inflammatory bowel disease and multiple previous failures to other immunosuppressants and/or biologics.

Wireless capsule endoscopy as a tool in diagnosing autoimmune enteropathy

Autoimmune enteropathy (AE) is an immune mediated illness of the intestinal mucosa. The cause is unknown, and the diagnosis is based on typical characteristics displayed. There is no gold standard for treatment. We present two adult cases of AE and demonstrate the challenges in establishing the diagnosis. The extensive diagnostic work up excluded other more common causes of protracted diarrhoea. Wireless capsule endoscopy (WCE) displayed universal small intestinal mucosal damage with shortened villi that led to the suspicion of AE in both patients. The diagnosis was confirmed with microscopy, showing shortened villi, villous blunting and hyperplasia of crypts in both patients. In one patient, deep crypt lymphocytosis with minimal intraepithelial lymphocytosis was found as well. Both patients were successfully treated with high-dose immunosuppressant therapy to induce and maintain remission. Use of WCE as a diagnostic tool was invaluable in establishing the diagnosis of AE.

Early investigational TNF receptor antagonists for the treatment of ulcerative colitis

INTRODUCTION

Ulcerative colitis (UC) is a life-long, immunologically mediated condition that results from an inappropriate activation of the mucosal immune system by intestinal luminal antigens in genetically susceptible individuals. TNF-α is a pro-inflammatory cytokine central to UC pathogenesis.

AREAS COVERED

This review examines the evidence for the use of the anti-TNF (αTNF) medications infliximab, adalimumab, certolizumab and golimumab in the management of UC. It highlights the newer biosimilar agents that are becoming available and the early stage investigation of an orally administered αTNF agent.

EXPERT OPINION

αTNF therapy is effective but only in a proportion of UC patients. As there is now strong evidence that UC is not just a single disease but a series of phenotypes with distinct genetic, serological and environmental aspects, understanding the heterogeneity of the innate immunological response in UC could allow for better targeted patient management. Identifying differences in the efficacy of the various αTNF agents is difficult as there are no head-to-head studies, but only infliximab has proven clinical efficacy in the management of acute severe colitis. Biosimilars to the αTNF agents are now available and with the added competition, medications costs should fall allowing for greater patient access.

Mycophenolate mofetil therapy in the management of inflammatory bowel disease--a retrospective case series and review

BACKGROUND AND AIMS

The role of mycophenolate mofetil (MMF) as an immunomodulatory drug in managing inflammatory bowel disease (IBD) is yet to be fully defined. We reviewed our experience of MMF in treating patients with IBD.

METHODS

Retrospective analysis was performed on all patients treated with MMF for inflammatory bowel disease between 2003 and 2011. Remission was assessed by reviewing clinical, endoscopic and laboratory indices.

RESULTS

We identified 36 patients, 23 male (64%), median age 46years (range 19-75). Nineteen patients had Crohn's disease, 16 with ulcerative colitis (UC), and one with indeterminate colitis. 33 patients (92%) had previously received azathioprine; 32 of whom discontinued this due to side-effects. 26 patients (72%) were concurrently taking oral corticosteroids. Median length of MMF treatment observed was 21.5months (IQR 9.7-31.6). At 8weeks, 29 patients (81%) had either achieved or maintained remission. After 6months, 19 of 33 patients (58%) were in sustained steroid-free remission. At the end of the observation period, 29 patients (81%) remained on MMF. 13 patients (36% of original treatment group; UC/IBDU 8, Crohn's 5) maintained steroid free remission. Median time in remission was 21.4months (IQR 11.0-30.0). Drug side-effects were experienced by 7 patients (19%), managed by dose reduction in 5 patients, with discontinuation in 2 (6%).

CONCLUSIONS

Mycophenolate mofetil may represent a promising treatment for inducing and maintaining remission in IBD patients intolerant of thiopurines. It may be of more value and relevance in ulcerative colitis, since less alternative proven therapies are available.

What is left when anti-tumour necrosis factor therapy in inflammatory bowel diseases fails?

The inflammatory bowel diseases (IBDs) are chronic incurable conditions that primarily present in young patients. Being incurable, the IBDs may be part of the patient’s life for many years and these conditions require therapies that will be effective over the long-term. Surgery in Crohn’s disease does not cure the disease with endoscopic recurrent in up to 70% of patients 1 year post resection. This means that, the patient will require many years of medications and the goal of the treating physician is to induce and maintain long-term remission without side effects. The development of the anti-tumour necrosis factor alpha (TNFα) agents has been a magnificent clinical advance in IBD, but they are not always effective, with loss of response overtime and, at times, discontinuation is required secondary to side effects. So what options are available if of the anti-TNFα agents can no longer be used? This review aims to provide other options for the physician, to remind them of the older established medications like azathioprine/6-mercaptopurine and methotrexate, the less established medications like mycophenolate mofetil and tacrolimus as well as newer therapeutic options like the anti-integins, which block the trafficking of leukocytes into the intestinal mucosa. The location of the intestinal inflammation must also be considered, as topical therapeutic agents may also be worthwhile to consider in the long-term management of the more challenging IBD patient. The more options that are available the more likely the patient will be able to have tailored therapy to treat their disease and a better long-term outcome.

A case series of de novo inflammatory bowel disease after kidney transplantation

Diarrhea, which is common after transplantation, may be due to infections and immunosuppressive therapy. Inflammatory bowel disease (IBD) de novo or as an exacerbation of pre-existent disease is a rare complication after kidney transplantation with pre-existing disease having a less aggressive clinical course than the de novo disease. Cytomegalovirus mismatch, prescription of tacrolimus instead of cyclosporine or mycophenolate mofetil rather than azathioprine as well as low-dose corticosteroid treatments have been linked to an increased incidence of IBD. This series of renal transplant recipients with de novo IBD showed a higher incidence and more aggressive course than that previously described, possibly related to increased use of tacrolimus with minimization of steroids.

Drug-induced inflammatory bowel disease and IBD-like conditions

The pathogenesis of inflammatory bowel disease (IBD) is multifactorial and results from an interaction between genetic, immunologic, microbial, and environmental factors. Certain drugs could act as a trigger for the disease and have been implicated in the development of new onset IBD in a number a studies. These relationships are based on case reports and cohort studies, as proving this in the context of randomized controlled trials would be difficult. Drugs that have been linked to causing or worsening IBD include isotretinoin, antibiotics, nonsteroidal antiinflammatory drugs, oral contraceptives, mycophenolate mofetil, etanercept, ipilimumab, and rituximab. Bowel preparation for colonoscopy has also been associated with aphthoid lesions that may be confused with IBD. However, given the source of these reports we have to be cautious in the interpretation of the data before concluding that these drugs trigger IBD and what is being observed is not related to other confounding factors. Different pathogenic mechanisms have been suggested for the different drugs listed above. In order to clarify the confusion a comprehensive literature review was performed with the goal of advancing the knowledge on this subject.

Fulminant ulcerative colitis despite maximal immunosuppression following liver transplantation: a case report and literature review

Inflammatory Bowel Disease (IBD) is thought to be the result of an overly aggressive immune response to ubiquitous antigens. Immuno -modulation and -suppression is therefore currently the treatment of choice. It was long anticipated that the course of pre-existing IBD should improve after orthotopic liver transplantation (OLT) due to increased immunosuppression. We report the case of a patient who developed acute fulminant colitis despite triple immunosuppression and mesalazine and review the relevant literature.

Inflammatory bowel disease unclassified

OBJECTIVE

Inflammatory bowel diseases (IBDs) are idiopathic, chronic, and inflammatory intestinal disorders. The two main types, ulcerative colitis (UC) and Crohn's disease (CD), sometimes mimic each other and are not readily distinguishable. The purpose of this study was to present a series of hospitalized cases, which could not initially be classified as a subtype of IBD, and to try to note roles of the terms indeterminate colitis (IC) and inflammatory bowel disease unclassified (IBDU) when such a dilemma arises.

METHODS

Medical records of 477 patients hospitalized due to IBD, during the period of January 2002 to April 2009, were retrospectively studied in the present paper. All available previous biopsies from endoscopies of these patients were reanalyzed.

RESULTS

Twenty-seven of 477 IBD patients (5.7%) had been initially diagnosed as having IBDU. Of them, 23 received colonoscopy and histological examinations in our hospital. A total of 90% (9/10) and 66.7% (4/6) of patients, respectively, had a positive finding via wireless capsule endoscopy (CE) and double-balloon enteroscopy (DBE). The barium-swallow or small bowel follow-through (SBFT) was performed on 11 patients. Positive changes were observed under computer tomographic (CT) scanning in 89.5% (17/19) of patients. Reasonable treatment strategies were employed for all patients.

CONCLUSIONS

Our data indicate that IBDU accounts for 5.7% of initial diagnoses of IBD. The definition of IBDU is valuable in clinical practice. For those who had no clear clinical, endoscopic, histological, or other features affording a diagnosis of either UC or CD, IBDU could be used parenthetically.