Anti-TNF levels and anti-drug antibodies, immunosuppressants and clinical outcomes in inflammatory bowel disease

Echinacea purpurea (L.) Moench extract suppresses inflammation by inhibition of C3a/C3aR signaling pathway in TNBS-induced ulcerative colitis rats

ETHNOPHARMACOLOGICAL RELEVANCE

Echinacea purpurea (L.) Moench (EP) is a perennial herbaceous flowering plant, commonly known as purple conical flower. It was widely used to treat skin inflammation and gastrointestinal diseases.

AIM OF STUDY

Ulcerative colitis (UC) is a chronic and nonspecific inflammatory disease. Recent evidence shows that immune disorders are involved in the pathogenesis of UC. To evaluate the protective effect of Echinacea purpurea (L.) Moench exact (EE) on UC and explore the role of complement system in the treatment of UC.

MATERIALS AND METHODS

UC model was induced in rats by 2,4,6-trinitrobenzene sulfonic acid (TNBS), and then rats were administered with EE for 10 days. Collect colon tissues for analysis of relevant mechanisms.

RESULTS

EE could reduce the weight loss and diarrhea of UC rats. In addition, EE could improve the integrity of intestinal epithelial barrier in UC rats. EE inhibited the level of proinflammatory cytokines and promoted the antioxidation. Furthermore, EE suppressed the expression of C3aR, CFB, CD55, TLR4 and NLRP3.

CONCLUSION

These results indicate that EE may achieve therapeutic effect by inhibiting C3a/C3aR signal pathway, suggesting that EE may be used as a medicinal plant to alleviate UC.

Effectiveness and safety of tofacitinib for ulcerative colitis: two-year results of the ICC Registry

BACKGROUND

Tofacitinib is an oral Janus kinase (JAK) inhibitor and is registered for the treatment of ulcerative colitis (UC). The effectiveness of tofacitinib has been evaluated up to 12 months of treatment.

AIM

The aim of this study was to assess the effectiveness and safety of 24 months of tofacitinib use in UC patients in the Netherlands.

METHODS

Patients initiating tofacitinib treatment were included in the ICC Registry, a nationwide, observational registry. Patients were prospectively evaluated for up to 24 months. The primary outcome was corticosteroid-free clinical remission (CSFR, Simple Clinical Colitis Activity Index [SCCAI] ≤2) at week 104. Secondary outcomes included biochemical remission (C-reactive protein (CRP) ≤5 mg/L and faecal calprotectin (FC) ≤250 μg/g), safety, and discontinuation rate.

RESULTS

We included 110 patients of whom 104 (94.5%) were anti-TNF experienced. After 104 weeks of tofacitinib, 31.8% (34/107) were in CSFR, 23.4% (25/107) in biochemical remission and 18.7% (20/107) in combined clinical and biochemical remission. Of the patients in CSFR at week 52, 76.5% (26/34) remained so after 104 weeks of treatment. Sixty-one patients (55.5%) discontinued tofacitinib after a median duration of 13 weeks (IQR 7-34). The main reasons for discontinuation were non-response (59%), loss of response (14.8%), and adverse events (18%). There were 33.9 possible tofacitinib-related adverse events per 100 patient-years during follow-up. Adverse events most probably related to tofacitinib were skin reactions and headaches. There were 6.4 herpes zoster infections per 100 patient-years.

CONCLUSION

Tofacitinib was effective in 31.8% of patients after 24 months of treatment.

2,3,5,4'-Tetrahydroxystilbene-2-O-β-D-glucoside, a major bioactive component from Polygoni multiflori Radix (Heshouwu) suppresses DSS induced acute colitis in BALb/c mice by modulating gut microbiota

BACKGROUND

Inflammatory bowel disease (IBD) includes ulcerative colitis (UC) and Crohn's disease (CD), which is a common idiopathic digestive disease without a specific cure or treatment for improvement. Because Polygoni multiflori Radix has a traditional medicinal use to treat intestinal diseases, and the water extract of this herbal medicine had a positive influence on dextran sulfate sodium (DSS) induced UC model in our study. Meanwhile 2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside (TSG) as the major component of the water extract of Polygoni multiflori Radix with yield of more than 10% exhibited the remarkable anti-inflammatory activity in vivo and in vitro, we predicted that TSG may contribute to benefit intestinal tract presented by the water extract of Polygoni multiflori Radix. Therefore, the present study aims to explore the pharmacological effect of this compound on UC model and its possible mechanism to regulate intestinal function through gut microbiota.

METHODS

Ulcerative colitis model was established in BALb/c mice by continuously administrating 3% (w/v) DSS aqueous solution for one week. The disease activity index (DAI), colon length, histopathological examination by H&E and the levels of tight junction proteins (TJP) by immunofluorescence staining were performed in ulcerative colitis model following the protocol. Furthermore, the levels of main inflammatory factors like TNF-α, IL-β, IL-6, and IL-10 were analyzed by the ELIZA kits for the further confirmation of anti-inflammatory activity of TSG on ulcerative colitis model. Finally, 16S rDNA sequencing technology was conducted to explore the composition and relative abundance of gut microbiota of different treatment groups.

RESULTS

TSG treatments effectively increased body weight about 5% of those in DSS group (p < 0.001) as well remarkably reduced the DAI scores to the 50% of those in DSS group (p < 0.001) in the UC model. TSG treatments of either 25 mg/kg (TSG-25) or 100 mg/kg (TSG-100) dosage restored epithelial barrier structure and exhibited obviously intact colon histology with reduced signs of inflammatory cells infiltration, preserved epithelia barrier, restored crypt structure, and increased numbers of goblet cells. TSG treatments could markedly lessen the histopathologic score two or three times than those in DSS group (p < 0.001). Especially for TSG-100 treatment, the fluorescence intensity of ZO-1 and Occludin were nearly back to 80% of those in normal group, and were 1.5 times more than those in the DSS group (p < 0.001). Additionally, direct evidence pointed to TSG as a therapeutically active molecule in the prevention and treatment of UC by significantly reducing the production of these pro-inflammatory cytokines like TNF-α, IL-1β, and IL-6 (p < 0.05-0.001) and increasing the levels of anti-inflammatory cytokine IL-10 (p < 0.05-0.001). Finally, it was found TSG treatments significantly raised the relative abundances of Firmicutes and Bacteroidetes with a dose-dependently and improved the homeostasis of the gut microbiota composition which disrupted by DSS through increasing genus level Lachnospiraceae_NK4A136 and decreasing genus level of Helicobacter, Bacteroides, Parabacteroides.

CONCLUSION

The present results suggested that TSG treatments had a desirable pharmacological effect on acute colitis induced by DSS in the mice as well showed the possible mechanism relate to improve the intestinal function through balancing the gut microbiota of intestinal flora.

Real-life experience with 4 years of golimumab persistence in ulcerative colitis patients

Golimumab has demonstrated its long-term efficacy and safety in ulcerative colitis in clinical trials, but no data of long-term persistence has been published from real world. To estimate long-term persistence of golimumab, as well as factors associated with longer persistence, in patients with ulcerative colitis in real life. Observational multicentre study including adult patients with ulcerative colitis treated with golimumab and with at least twelve months of follow-up. We included 190 patients, 105 (55.26%) naive to anti-TNF, with mean disease duration of 9.32 ± 8.09 years. Probability of persistence was 63%, 46%, 39% and 27% at 1, 2, 3 and 4 years, respectively. Persistence was lower in patients with primary failure to previous anti-TNF. Eighty-two (43.16%) patients needed dose intensification during follow-up, with a mean time until intensification of 8.03 ± 8.64 months. Dose intensification and lower disease duration predicted higher persistence with golimumab (p = 0.037 and p = 0.008, respectively). During a follow-up of 17.25 ± 15.83 months, 32 (16.5%) patients needed hospitalisation and 11 (6%) underwent colectomy. No unexpected adverse events were reported. Golimumab has demonstrated good persistence and safety profile for long treatment in ulcerative colitis patients.

Pharmacological Autophagy Regulators as Therapeutic Agents for Inflammatory Bowel Diseases

The arsenal of effective molecules to treat patients with chronic inflammatory bowel diseases (IBDs) remains limited. These remitting-relapsing diseases have become a global health issue and new therapeutic strategies are eagerly awaited to regulate the course of these disorders. Since the association between autophagy-related gene polymorphism and an increased risk of Crohn's disease (CD) has been discovered, a new domain of investigation has emerged, focused on the intracellular degradation system, with the objective of generating new medicines that are safer and more targeted. This review summarizes the drugs administered to IBD patients and describes recently emerged therapeutic agents. We compile evidence on the contribution of autophagy to IBD pathogenesis, give an overview of pharmacological autophagy regulators in animal models of colitis, and propose novel therapeutic avenues based on autophagy components.

Incidence, Prevention and Management of Anti-Drug Antibodies Against Therapeutic Antibodies in Inflammatory Bowel Disease: A Practical Overview

The introduction of biologic therapy has revolutionized the treatment of inflammatory bowel disease (IBD). However, like all therapeutic proteins, monoclonal antibodies have immunogenic potential which is influenced by multiple drug- and patient-related factors. The reported incidence of anti-drug antibodies (ADAs) towards biologic drugs in IBD varies greatly in the literature and depends not only on differences in sensitization but also on the assay methodology and the timepoint of measurement. Sensitization with formation of ADAs is associated with an increased risk of infusion reactions, accelerated drug clearance, and a loss of response (LOR) to drug. Recently, a greater understanding of the pharmacokinetics of therapeutic antibodies has led to the development of new strategies to reduce immunogenicity and more efficient use of these drugs. These preventive strategies include regular scheduled dosing with maintenance of stable therapeutic trough drug concentrations, and co-administration of an immunosuppressive. Sub-therapeutic drug concentrations with low levels of ADAs can generally be overcome with dose escalation, whereas the presence of high concentrations of ADAs requires a switch to another therapeutic agent.

Mucosal Healing in Ulcerative Colitis: A Comprehensive Review

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by periods of remission and periods of relapse. Patients often present with symptoms such as rectal bleeding, diarrhea and weight loss, and may require hospitalization and even colectomy. Long-term complications of UC include decreased quality of life and productivity and an increased risk of colorectal cancer. Mucosal healing (MH) has gained progressive importance in the management of UC patients. In this article, we review the endoscopic findings that define both mucosal injury and MH, and the strengths and limitations of the scoring systems currently available in clinical practice. The basic mechanisms behind colonic injury and MH are covered, highlighting the pathways through which different drugs exert their effect towards reducing inflammation and promoting epithelial repair. A comprehensive review of the evidence for approved drugs for UC to achieve and maintain MH is provided, including a section on the pharmacokinetics of anti-tumor necrosis factor (TNF)-α drugs. Currently approved drugs with proven efficacy in achieving MH in UC include salicylates, corticosteroids (induction only), calcineurin inhibitors (induction only), thiopurines, vedolizumab and anti-TNFα drugs (infliximab, adalimumab, and golimumab). MH is of crucial relevance in the outcomes of UC, resulting in lower incidences of clinical relapse, the need for hospitalization and surgery, as well as reduced rates of dysplasia and colorectal cancer. Finally, we present recent evidence towards the need for a more strict definition of complete MH as the preferred endpoint for UC patients, using a combination of both endoscopic and histological findings.

The impact of immunogenicity of TNFα inhibitors in autoimmune inflammatory disease. A systematic review and meta-analysis

BACKGROUND

Monoclonal antibodies drugs directed against TNFα, TNFα inhibitors, are immunogenic, and consequent anti-drug antibodies (ADA) formation may decrease the functional drug concentration, resulting in a loss of response. We evaluated the impact of ADA on TNFα therapeutic response.

METHODS

We considered studies enrolling adult patients affected by autoimmune inflammatory disease in therapy with TNFα inhibitors. We collected data about study and population characteristics, treatment dosage, determination of ADA and adverse events (AE). We combined data in meta-analysis, calculating risk ratios (RR) for each study. p-Values<0.05 were considered as statistically significant. Methodological quality was evaluated. Analyses were performed with the STATA 11 and RevMan 5.3 softwares.

RESULTS

We included 34 studies enrolling 4273 patients. Of these, 794 (18.6%) developed ADA. Our analysis showed a significant reduction of response (RR 0.43, 95%CI 0.3-0.63) in patients with ADA respect to patients without, especially in patients treated with Infliximab (RR 0.37) or Adalimumab (RR 0.40). Furthermore, the administration of TNFα inhibitors produced a reaction at the infusion site in 17%, infection in 30% and serious AE in 5% of patients.

CONCLUSION

Detectable ADA significantly reduced TNFα inhibitors response. Drug administration can also cause injection site reaction and infections. Early detection of serum ADA levels may improve patients' management. Currently, there are many indications about the use of immunogenicity tests to guide the therapy, but information regarding how to implement it in clinical practice is needed.

Therapeutic Drug Monitoring and Clinical Outcomes in Immune Mediated Diseases: The Missing Link

As the incidence of inflammatory bowel diseases and the number of patients treated with anti-TNF agents keep on increasing so are the phenomena of primary non response (PNR) and secondary loss of response (SLR) to these medications. Traditionally PNR and SLR have been managed empirically-that is, switching medications for PNR and increasing the anti-TNF dose for SNR. More recently an approach based on testing drug levels and antibodies to the drug (therapeutic drug monitoring) has gained increasing popularity in the management of inflammatory bowel diseases. However, while this strategy might offer an insight into the mechanisms leading to PNR/SLR it often falls short of providing a simple, reproducible method to manage these issues in clinical practice. Here, we will review the currently recommended therapeutic strategies when using therapeutic drug monitoring; the evidence for and against such approach and the current standard strategies in Rheumatology (the specialty with the largest and longest experience with anti-TNF agents). We will then discuss the possible reasons of the shortcomings of therapeutic drug monitoring and the rationale and need to move the therapeutic target to the disease burden in inflammatory bowel diseases-along with the supporting preliminary evidence. Finally, we will focus on future crucial studies that need to be done to make approaches to PNR/SLR more rigorous and at the same time user-friendly for the practicing gastroenterologist.

Posttranslational Modifications and the Immunogenicity of Biotherapeutics

Whilst the amino acid sequence of a protein is determined by its gene sequence, the final structure and function are determined by posttranslational modifications (PTMs), including quality control (QC) in the endoplasmic reticulum (ER) and during passage through the Golgi apparatus. These processes are species and cell specific and challenge the biopharmaceutical industry when developing a production platform for the generation of recombinant biologic therapeutics. Proteins and glycoproteins are also subject to chemical modifications (CMs) both in vivo and in vitro. The individual is naturally tolerant to molecular forms of self-molecules but nonself variants can provoke an immune response with the generation of anti-drug antibodies (ADA); aggregated forms can exhibit enhanced immunogenicity and QC procedures are developed to avoid or remove them. Monoclonal antibody therapeutics (mAbs) are a special case because their purpose is to bind the target, with the formation of immune complexes (ICs), a particular form of aggregate. Such ICs may be removed by phagocytic cells that have antigen presenting capacity. These considerations may frustrate the possibility of ameliorating the immunogenicity of mAbs by rigorous exclusion of aggregates from drug product. Alternate strategies for inducing immunosuppression or tolerance are discussed.