Biologic therapies in clinical development for the treatment of rheumatoid arthritis

Therapeutic and Prophylactic Use of Oral, Low-Dose IFNs in Species of Veterinary Interest: Back to the Future

Cytokines are important molecules that orchestrate the immune response. Given their role, cytokines have been explored as drugs in immunotherapy in the fight against different pathological conditions such as bacterial and viral infections, autoimmune diseases, transplantation and cancer. One of the problems related to their administration consists in the definition of the correct dose to avoid severe side effects. In the 70s and 80s different studies demonstrated the efficacy of cytokines in veterinary medicine, but soon the investigations were abandoned in favor of more profitable drugs such as antibiotics. Recently, the World Health Organization has deeply discouraged the use of antibiotics in order to reduce the spread of multi-drug resistant microorganisms. In this respect, the use of cytokines to prevent or ameliorate infectious diseases has been highlighted, and several studies show the potential of their use in therapy and prophylaxis also in the veterinary field. In this review we aim to review the principles of cytokine treatments, mainly IFNs, and to update the experiences encountered in animals.

Cost-effectiveness of abatacept, rituximab, and TNFi treatment after previous failure with TNFi treatment in rheumatoid arthritis: a pragmatic multi-centre randomised trial

Introduction

For patients with rheumatoid arthritis (RA) whose treatment with a tumour necrosis factor inhibitor (TNFi) is failing, several biological treatment options are available. Often, another TNFi or a biological with another mode of action is prescribed. The objective of this study was to compare the effectiveness and cost-effectiveness of three biologic treatments with different modes of action in patients with RA whose TNFi therapy is failing.

Methods

We conducted a pragmatic, 1-year randomised trial in a multicentre setting. Patients with active RA despite previous TNFi treatment were randomised to receive abatacept, rituximab or a different TNFi. The primary outcome (Disease Activity Score in 28 joints) and the secondary outcomes (Health Assessment Questionnaire Disability Index and 36-item Short Form Health Survey scores) were analysed using linear mixed models. Cost-effectiveness was analysed on the basis of incremental net monetary benefit, which was based on quality-adjusted life-years (calculated using EQ-5D scores), and all medication expenditures consumed in 1 year. All analyses were also corrected for possible confounders.

Results

Of 144 randomised patients, 5 were excluded and 139 started taking abatacept (43 patients), rituximab (46 patients) or a different TNFi (50 patients). There were no significant differences between the three groups with respect to multiple measures of RA outcomes. However, our analysis revealed that rituximab therapy is significantly more cost-effective than both abatacept and TNFi over a willingness-to-pay range of 0 to 80,000 euros.

Conclusions

All three treatment options were similarly effective; however, when costs were factored into the treatment decision, rituximab was the best option available to patients whose first TNFi treatment failed. However, generalization of these costs to other countries should be undertaken carefully.

Trial registration

Netherlands Trial Register number NTR1605. Registered 24 December 2008.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0630-5) contains supplementary material, which is available to authorized users.

Burn wound γδ T-cells support a Th2 and Th17 immune response

Major burn triggers immune dysfunction, which is associated with wound healing complications. Gamma-δ T-cells have been shown to be important in postburn inflammation and wound healing; however, their cytokine phenotype at the burn wound site is unknown. C57BL/6 male mice were subjected to a major burn (25% TBSA, third degree) or sham treatment. At 3 hours, 3 days, and 7 days thereafter, skin samples were collected and subjected to dispase and trypsin digestion to isolate single cells. The cells were phenotyped and evaluated for cytokine profiles by flow cytometry. Th1 cells were defined as interferon (IFN)γ positive, Th2 cells were defined as interleukin (IL)-10 positive, and Th17 cells were defined as IL-17 positive. At 7 days after burn a shift toward Th2 and Th17 positive T-cells at the wound site was observed. Further analysis revealed that at 3-hour postinjury the percentage of γδ T-cells positive for IFNγ, IL-10, and IL-17 were comparable between sham and burn skin samples. At 3 days and 7 days postinjury the percentage of cells positive for each cytokine increased; however, the increase was significantly greater for IL-10 and IL-17, as compared with IFNγ (ie, 9-20-fold vs 3-fold). Skin αβ T-cells preferentially produced IFNγ (~20%), which was unaffected by burn injury. These data demonstrate that burn wound γδ T-cells are activated for enhanced cytokine production and display a shift toward a Th2 and/or Th17 phenotype. In contrast, burn wound αβ T-cells were not activated for enhanced cytokine production.

Certolizumab pegol (CDP870) for rheumatoid arthritis in adults

BACKGROUND

Tumour necrosis factor (TNF)-alpha inhibitors are beneficial for the treatment of rheumatoid arthritis (RA) in terms of reducing the risk of joint damage, improving physical function and improving quality of life. This Cochrane review is an update of a review of the treatment of RA with certolizumab pegol that was first published in 2011.

OBJECTIVES

To assess the clinical benefits and harms of certolizumab pegol (CDP870) in patients with RA who have not responded well to conventional disease-modifying anti-rheumatic drugs (DMARDs).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library 2014, Issue 5), MEDLINE, EMBASE, Scopus, TOXLINE, Web of Knowledge; websites of the US Food and Drug Administration (FDA) and European Medicines Evaluation Agency (EMEA); reference lists of articles; and searched http/clinicaltrials.gov. The searches were updated from 2009 (date of last search for the original review) to 5 June 2014.

SELECTION CRITERIA

Randomised controlled trials that compared certolizumab pegol with any other agent including placebo or methotrexate (MTX) in adult patients with active RA despite current or prior treatment with conventional disease-modifying anti-rheumatic drugs (DMARDs), such as MTX.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed search results, trial quality and extracted data. Disagreements were resolved by discussion or referral to a third author.

MAIN RESULTS

Eleven trials were included in this update. Ten (4324 patients) were included in the pooled analysis for benefits, five more than previously, and 10 (3711 patients) in the pooled analysis for harms, four more trials (1930 patients) than previously. The duration of follow-up varied from 12 to 52 weeks and the range of doses of certolizumab pegol varied from 50 to 400 mg given subcutaneously (sc). In phase III trials, the control was placebo plus MTX in five trials and placebo in four trials. The risk of bias of the included studies was assessed as low but there may have been a risk of attrition bias.Statistically significant improvements were observed at 24 weeks with the approved dose of 200 mg certolizumab pegol every other week, in 1) American College of Rheumatology (ACR) 50% improvement: 27% absolute improvement (95% CI 20% to 33%), NNT of 4 (95% CI 3 to 8), risk ratio (RR) 3.80 (95% CI 2.42 to 5.95); 2) the Health Assessment Questionnaire (HAQ): -12% absolute improvement (95% CI -9% to -14%), NNT of 6 (95% CI 5 to 8), mean difference (MD) - 0.35 (95% CI -0.43 to -0.26) (scale 0 to 3); 3) Disease Activity Score (DAS) remission improvement: absolute improvement 11% (95% CI 8% to 15%), NNT of 9 (95% CI 4 to 20), RR 8.47 (95% CI 4.15-17.28); and 4) radiological changes: erosion score (ES) absolute improvement -0.29% (95% CI -0.42% to -0.17%), NNT of 6 (95% CI 4 to 10), MD -0.67 (95% CI -0.96 to -0.38) (scale 0 to 230). Serious adverse events were statistically significantly more frequent for certolizumab pegol (200 mg every other week) with an absolute rate difference of 4% (95% CI 2% to 6%), NNTH of 32 (95% CI 17 to 88), Peto odds ratio (OR) 1.77 (95% CI 1.27 to 2.46). There was a statistically significant increase in all withdrawals in the placebo groups (for all doses and all follow-ups) with an absolute rate difference of -34% (95% CI -18% to -50%), NNTH of 4 (95% CI 3 to 5), NNTH of 4 (95% CI 3 to 5), RR 0.42 (95% CI 0.36 to 0.50); and there was a statistically significant increase in all withdrawals due to adverse events in the certolizumab groups (for all doses and all follow-up) with an absolute rate difference of 2% (95% CI 1% to 3%), NNTH of 55 (95% CI 27 to 238), Peto OR 1.66 (95% CI 1.15 to 2.37).The risk of bias was low and the quality of evidence was downgraded to moderate because of high rates of dropouts (> 20%) in most of the trials. We did not find any problems with inconsistency, indirectness, imprecision or publication bias.

AUTHORS' CONCLUSIONS

The results and conclusions did not change from the previous review. There is moderate-level evidence from randomised controlled trials that certolizumab pegol alone or combined with methotrexate is beneficial in the treatment of RA. Adverse events were more frequent with active treatment. We found a potential risk of serious adverse events.

Biological therapies for rheumatoid arthritis: progress to date

Biologic drugs for the management of rheumatoid arthritis (RA) have revolutionized the therapeutic armamentarium with the development of several novel monoclonal antibodies, which include murine, chimeric, humanized, fully human antibodies and fusion proteins. These biologics bind to their targets with high affinity and specificity. Since 1998, nine different biologics have been approved by the US Food and Drug Administration (FDA) and European Medicines Agency (EMA) for the treatment of RA, and several others are in different stages of clinical trials. This field is in continuous evolution and new biologics are tested every year. Therefore a precise analysis is required in order to have a detailed and updated state of the art of this field. In this review, our main aim is to analyse all available biological therapies that are FDA and EMA approved for the treatment of RA and also those that are in clinical trials for the management of RA patients.

A whole blood in vitro cytokine release assay with aqueous monoclonal antibody presentation for the prediction of therapeutic protein induced cytokine release syndrome in humans

The administration of several monoclonal antibodies (mAbs) to humans has been associated with acute adverse events characterized by clinically significant release of cytokines in the blood. The limited predictive value of toxicology species in this field has triggered intensive research to establish human in vitro assays using peripheral blood mononuclear cells or blood to predict cytokine release in humans. A thorough characterization of these assays is required to understand their predictive value for hazard identification and risk assessment in an optimal manner, and to highlight potential limitations of individual assay formats. We have characterized a whole human blood cytokine release assay with only minimal dilution by the test antibodies (95% v/v blood) in aqueous presentation format, an assay which has so far received less attention in the scientific world with respect to the evaluation of its suitability to predict cytokine release in humans. This format was compared with a human PBMC assay with immobilized mAbs presentation already well-characterized by others. Cytokine secretion into plasma or cell culture supernatants after 24h incubation with the test mAbs (anti-CD28 superagonist TGN1412-like material (TGN1412L), another anti-CD28 superagonistic mAb (ANC28.1), a T-cell depleting mAb (Orthoclone™), and a TGN1412 isotype-matched control (Tysabri™) not associated with clinically-relevant cytokine release) was detected by a multiplex assay based on electrochemiluminescent excitation. We provide proof that this whole blood assay is a suitable new method for hazard identification of safety-relevant cytokine release in the clinic based on its ability to detect the typical cytokine signatures found in humans for the tested mAbs and on a markedly lower assay background and cytokine release with the isotype-matched control mAb Tysabri™ - a clear advantage over the PBMC assay. Importantly, quantitative and qualitative differences in the relative cytokine responses to the individual mAbs, in the concentration-response relationships and the prominent cytokine signatures for individual mAbs in the two formats reflect diverging mechanisms of cytokine release and different levels of dependency on high density coating even for two anti-CD28 super-agonistic antibodies. These results clearly show that one generic approach to assessment of cytokine release using in vitro assays is not sufficient, but rather the choice of the method, i.e. applying the whole blood assay or the PBMC assay needs to be well considered depending on the target characteristics and the mechanistic features of the therapeutic mAbs being evaluated.

Ethanol extract of Elaeocarpus petiolatus inhibits lipopolysaccharide-induced inflammation in macrophage cells

Elaeocarpus petiolatus is known to exert active oxygen scavenging, anti-aging, and whitening actions. However, the biological effects of E. petiolatus on inflammation and the underlying mechanisms are yet to be established. In the present study, we investigated the anti-inflammatory effects of the ethanol extract from E. petiolatus (EPE) bark in murine Raw264.7 macrophages stimulated with lipopolysaccharide (LPS). EPE inhibited the production of PGE(2), TNF-α, and IL-1β in a dose-dependent manner in Raw264.7 cells stimulated with LPS. The decrease in PGE(2) production was correlated with reduced COX-2 expression. Furthermore, EPE suppressed the phosphorylation of extracellular signal-related kinases (ERK), c-Jun N-terminal kinase (JNK), and p38 as well as translocation of the NF-κB p65 subunit from the cytosol to nucleus. Our results suggest that EPE exerts anti-inflammatory activity through inhibition of inflammatory mediators, such as PGE(2), TNF-α, and IL-1β, and downregulation of COX-2 via suppression of NF-κB translocation and phosphorylation of ERK, JNK, and p38 in LPS-stimulated Raw264.7 cells.

CD28 family and chronic rejection: "to belatacept...And beyond!"

Kidneys are one of the most frequently transplanted human organs. Immunosuppressive agents may prevent or reverse most acute rejection episodes; however, the graft may still succumb to chronic rejection. The immunological response involved in the chronic rejection process depends on both innate and adaptive immune response. T lymphocytes have a pivotal role in chronic rejection in adaptive immune response. Meanwhile, we aim to present a general overview on the state-of-the-art knowledge of the strategies used for manipulating the lymphocyte activation mechanisms involved in allografts, with emphasis on T-lymphocyte costimulatory and coinhibitory molecules of the B7-CD28 superfamily. A deeper understanding of the structure and function of these molecules improves both the knowledge of the immune system itself and their potential action as rejection inducers or tolerance promoters. In this context, the central role played by CD28 family, especially the relationship between CD28 and CTLA-4, becomes an interesting target for the development of immune-based therapies aiming to increase the survival rate of allografts and to decrease autoimmune phenomena. Good results obtained by the recent development of abatacept and belatacept with potential clinical use aroused better expectations concerning the outcome of transplanted patients.

Association of interleukin 4 -589T/C polymorphism with T(H)1 and T(H)2 bias and sepsis in Chinese major trauma patients

BACKGROUND

Interleukin (IL)-4 is a pleiotropic cytokine, severed as an important component of the adaptive immune system, and implicated in the pathophysiology of sepsis. Data from other studies show that the -589T/C polymorphism in IL-4 promoter may alter IL-4 expression and susceptibility of inflammatory or autoimmune diseases. Whether this genetic variation is associated with sepsis susceptibility is unknown. The aim of this study was to search for the association of IL-4 -589T/C with the susceptibility to sepsis.

METHODS

The polymorphism was genotyped among 308 severe trauma patients using restriction fragment length polymorphism polymerase chain reaction. The IL-4 and interferon-γ levels in the supernatants were determined with enzyme-linked immunosorbent assay.

RESULTS

The IL-4/-589C allele was shown to be significantly associated with higher plasma IL-4 and lower interferon-γ production after lipopolysaccharide stimulation, indicating its effect on regulating T helper T(H)1/T(H)2 balance. Moreover, homozygosity and heterozygosity for the -589C were associated with an increased susceptibility of sepsis (p = 0.009; OR, 1.69; 95% confidence interval, 1.14-2.51). There was no relationship between the IL-4 -589T/C and multiple organ dysfunction scores in severe trauma patients.

CONCLUSIONS

These results suggest that the IL-4 -589T/C polymorphism might affect T(H)1/T(H)2 balance and predispose trauma patients to susceptibility sepsis.

Microfluidics for T- lymphocyte cell separation and inflammation monitoring in burn patients

Severe burns result in T lymphocyte specific immunologic changes. In addition to decreased levels of circulating lymphocytes, changes in cytokine secretion and receptor expression also take place. Our finer understanding of the inflammatory response has led to the development of immune-targeted therapeutics, requiring specialized gene-expression monitoring. The emerging field of bio-micro-electromechanical systems can be used to isolate highly pure T lymphocytes in a clinically relevant and timely manner for downstream genomic analysis. Blood samples from healthy volunteers and burn-injured patients were introduced into microfluidic devices developed in our laboratory. Utilizing cell-affinity chromatography for positive selection of T lymphocytes, the devices served as a platform for RNA extraction and downstream cytokine analysis via quantitative real-time polymerase chain reaction (PCR). From a 0.5-mL whole blood sample, the microfluidic devices captured highly pure T lymphocytes from healthy volunteers and burn-injured patients. Cell capture was of sufficient quantity, and extracted RNA was of sufficient quality, for evaluating the gene expression of cytokines: interferon-gamma, interleukin-2, interleukin-4, and interleukin-10. Microfluidics is a useful tool in processing blood from burn-injured patients. Though in its very early stages of development, cell-specific information obtained by this platform/technology will likely be an important component of near-patient molecular diagnostics and personalized medicine.

Certolizumab pegol (CDP870) for rheumatoid arthritis in adults

BACKGROUND

TNF-alpha inhibitors have been shown to reduce the risk of joint damage and improve physical function and quality of life in people with rheumatoid arthritis (RA). This is the first Cochrane review of certolizumab pegol, a new TNF-alpha inhibitor.

OBJECTIVES

To assess the effectiveness and safety of certolizumab pegol (CDP870) in patients with RA who have not responded well to conventional disease modifying anti-rheumatic drugs (DMARDs).

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library 2009, Issue 3),  MEDLINE (1966 to November 2009), EMBASE (1966 to November 2009), Scopus (January 2004 to November 2009), TOXLINE (until November 2009), Web of Knowledge (until November 2009); websites of the US Food and Drug Administration (FDA) and European Medicines Evaluation Agency (EMEA) (until November 2009), and reference lists of articles.

SELECTION CRITERIA

Randomised controlled trials that compared certolizumab pegol with any other agent including placebo or methotrexate (MTX) in adult RA patients with active rheumatoid arthritis despite current or prior treatment with conventional DMARDs, such as methotrexate (MTX).

DATA COLLECTION AND ANALYSIS

Two authors independently assessed search results, trial quality and extracted data.

MAIN RESULTS

Five trials were included. We included in the analysis 2394 people for effectiveness and 2094 people for safety. The duration of follow-up was from 12 to 52 weeks, and the range of doses of certolizumab pegol were from 50 to 400 mg subcutaneously (sc). In three trials the control was placebo plus methotrexate (MTX) and in two trials it was just placebo. Significant improvements were observed at 24 weeks with the approved dose of 200 mg certolizumab pegol: American College of Rheumatology (ACR) 50% improvement: risk ratio (RR) 6.01 (95% CI 3.84 to 9.40) with an absolute benefit of 29% (95% CI 25% to 34%), number needed to treat to benefit (NNTB) of 4 (3 to 5) and the Health Assessment Questionnaire (HAQ) mean difference (MD) - 0.39 (95% CI -0.45 to -0.32) (scale 0 to 3). At 52 weeks the results were quite similar: ACR 50% improvement RR 5.27 (95% CI 3.19 to 8.71), HAQ mean difference (MD) - 0.42 (95% CI -0.52 to -0.32). Serious adverse events were more frequent for certolizumab pegol 200 mg, Peto OR 2.02 (95% CI 1.24 to 3.30). The most common adverse events with certolizumab pegol 200 mg were: upper respiratory tract infections, Peto OR 2.21 (95% CI 1.15 to 4.25); hypertension, Peto OR 2.81 (95% CI 1.38 to 5.75); and nasopharyngitis, Peto OR 2.71 (95% CI 1.30 to 5.66).

AUTHORS' CONCLUSIONS

With an overall high grade of evidence this review revealed an improvement of clinical results (ACR50, 28 joint disease activity score (DAS-28) remission and HAQ scores) with certolizumab pegol. Adverse events were more frequent with certolizumab; there was a statistically significant increase in the number of serious adverse events, infections and hypertension.

Mucin from rheumatoid arthritis synovial fluid enhances interleukin-6 production by human peripheral blood mononuclear cells

The carbohydrate chains represented by mucins (MUCs) are expressed by a variety of normal and malignant secretory epithelial cells and induce a variety of immunoreactions. To find new mucins related to the pathogenesis of rheumatoid arthritis (RA), we examined high-molecular-weight molecules inducing cytokines on human peripheral blood mononuclear cells (PBMCs) in synovial fluid from affected joints. We found a high-molecular-weight substance that induces interleukin 6 production on PBMCs in RA synovial fluid on gel filtration. MUC-1 was present in the resulting fractions, although they had been purified by CsCl density gradient centrifugation. We also found that MUC-1 was expressed on synovial cells and infiltrating inflammatory mononuclear cells on the sublining layer and lymphoid follicles in RA synovial tissues. CD68-positive superficial synovial cells colocalized with MUC-1 and CD68-positive macrophages were in contact with MUC-1-positive mononuclear cells. These findings imply that mucins, including MUC-1, may be related to immunoinflammatory reactions in the pathogenesis of RA.

Schisantherin A exhibits anti-inflammatory properties by down-regulating NF-kappaB and MAPK signaling pathways in lipopolysaccharide-treated RAW 264.7 cells

Schisantherin A, a dibenzocyclooctadiene lignan isolated from the fruit of Schisandra sphenanthera, has been used as an antitussive, tonic, and sedative agent under the name of Wuweizi in Chinese traditional medicine. In the present study, we carry out a screening program to identify the anti-inflammatory potentials of schisantherin A. We found that schisantherin A reduced lipopolysaccharide (LPS (1 mg/L))-induced levels of TNF-alpha, IL-6, NO, and PGE2 (p<0.01 or p<0.05), and also reduced levels of iNOS and COX-2 in RAW 264.7 macrophages in a concentration-dependent manner. We further investigated signal transduction mechanisms to determine how schisantherin A affects. RAW264.7 cells were pretreated with 0.5, 2.5, or 25 mg/L of schisantherin A 1 h prior to treatment with 1 mg/L of LPS. Thirty minutes later, cells were harvested and mitogen activated protein kinases (MAPKs) activation and I kappaB alpha was measured by Western blot. Alternatively, cells were fixed and nuclear factor-kappaB (NF-kappaB) activation was measured using immunocytochemical analysis. Signal transduction studies showed that schisantherin A significantly inhibited extracellular signal-regulated kinase (ERK), p38, and c-jun NH2-terminal kinase (JNK) phosphorylation protein expression. Schisantherin A also inhibited p65-NF-kappaB translocation into the nucleus by I kappaB alpha degradation. By using specific inhibitors of ERK, JNK and p38, we found that schisantherin A may inhibit TNF-alpha mostly through ERK pathway. Therefore, schisantherin A may inhibit LPS-induced production of inflammatory cytokines by blocking NF-kappaB and MAPKs signaling in RAW264.7 cells.

Regulation of inflammatory mediators in lipopolysaccharide-stimulated RAW 264.7 cells by 2''-hydroxy-3''-en-anhydroicaritin involves down-regulation of NF-kappaB and MAPK expression

2''-hydroxy-3''-en-anhydroicaritin, a flavone, was isolated from the Chinese medicinal herb Epimedium brevicornum for the first time. In our previous study, we have carried out a screening program to identify the anti-inflammatory potentials of 2''-hydroxy-3''-en-anhydroicaritin. In the present study, we further found that this compound regulated lipopolysaccharide (LPS)-induced levels of nitric oxide (NO), and prostaglandin E(2) (PGE(2)) (**p<0.01 or *p<0.05), and reduced levels of iNOS and COX-2 in RAW 264.7 macrophages in a concentration-dependent manner. We further investigated signal transduction mechanisms to determine how 2''-hydroxy-3''-en-anhydroicaritin affects RAW264.7 macrophages pretreated with 0.5, 2.5, or 12.5mg/L of 2''-hydroxy-3''-en-anhydroicaritin 1h prior to treatment with 1mg/L of LPS. Thirty minutes later, cells were harvested and mitogen-activated protein kinases (MAPK) activation and I kappaB alpha were measured by western blotting. Alternatively, the macrophages were fixed and nuclear factor-kappaB (NF-kappaB) activation was measured by immunocytochemical analysis. Signal transduction studies showed that the flavone significantly inhibited extracellular signal-regulated kinase (ERK), p38, and c-jun NH2-terminal kinase (JNK) phosphorylation protein expression. The flavone also inhibited p65-NF-kappaB translocation into the nucleus by I kappaB alpha degradation. Therefore, 2''-hydroxy-3''-en-anhydroicaritin may inhibit LPS-induced production of inflammatory cytokines by blocking NF-kappaB and MAPK signaling in RAW264.7 cells.

Safety and immunotoxicity assessment of immunomodulatory monoclonal antibodies

Most therapeutic monoclonal antibodies (mAbs) licensed for human use or in clinical development are indicated for treatment of patients with cancer and inflammatory/autoimmune disease and as such, are designed to directly interact with the immune system. A major hurdle for the development and early clinical investigation of many of these immunomodulatory mAbs is their inherent risk for adverse immune-mediated drug reactions in humans such as infusion reactions, cytokine storms, immunosuppression and autoimmunity. A thorough understanding of the immunopharmacology of a mAb in humans and animals is required to both anticipate the clinical risk of adverse immunotoxicological events and to select a safe starting dose for first-in-human (FIH) clinical studies. This review summarizes the most common adverse immunotoxicological events occurring in humans with immunomodulatory mAbs and outlines non-clinical strategies to define their immunopharmacology and assess their immunotoxic potential, as well as reduce the risk of immunotoxicity through rational mAb design. Tests to assess the relative risk of mAb candidates for cytokine release syndrome, innate immune system (dendritic cell) activation and immunogenicity in humans are also described. The importance of selecting a relevant and sensitive toxicity species for human safety assessment in which the immunopharmacology of the mAb is similar to that expected in humans is highlighted, as is the importance of understanding the limitations of the species selected for human safety assessment and supplementation of in vivo safety assessment with appropriate in vitro human assays. A tiered approach to assess effects on immune status, immune function and risk of infection and cancer, governed by the mechanism of action and structural features of the mAb, is described. Finally, the use of immunopharmacology and immunotoxicity data in determining a minimum anticipated biologic effect Level (MABEL) and in the selection of safe human starting dose is discussed.

Current status and challenges of cytokine pharmacology

The major concern of pharmacology about cytokines has originated from plentiful data showing association between gross changes in their production and pathophysiological processes. Despite the enigmatic role of cytokines in diseases, a number of them have become a subject of cytokine and anti-cytokine immunotherapies. Production of cytokines can be influenced by many endogenous and exogenous stimuli including drugs. Cells of the immune system, such as macrophages and lymphocytes, are richly endowed with receptors for the mediators of physiological functions, such as biogenic amines, adenosine, prostanoids, steroids, etc. Drugs, agonists or antagonists of these receptors can directly or indirectly up- and down-regulate secretion of cytokines and expression of cytokine receptors. Vice versa, cytokines interfere with drug pharmacokinetics and pharmacodynamics through the interactions with cytochrome P450 and multiple drug resistance proteins. The aim of the review is to encourage more intensive studies in these fields of cytokine pharmacology. It also outlines major areas of searching promising candidates for immunotherapeutic interventions.

Abatacept in biologic-naïve patients and TNF inadequate responders: clinical data in focus

BACKGROUND

Advances in the understanding of rheumatoid arthritis (RA) immunopathogenesis support the hypothesis for a 'window of opportunity' for therapeutic intervention in RA and the need for rapid and effective treatment strategies, with the ultimate goal of alleviating symptoms and halting progressive joint damage. Biologic therapies targeting pro-inflammatory cytokines have significantly improved the outlook for patients with RA; however, some patients still experience inadequate treatment responses. Recently, therapeutic agents targeting alternative pathways have been developed. One such therapy--abatacept--targets T-cell activation and is approved in the United States for treatment of moderate-to-severe RA and juvenile idiopathic arthritis.

OBJECTIVE

To overview the efficacy and safety of abatacept in the treatment of adult patients with active RA and an inadequate response to methotrexate (MTX) or tumor necrosis factor (TNF) antagonists. SEARCH METHODOLOGY: A comprehensive literature search was performed using the National Library of Medicine (MEDLINE), EMBASE and BIOSIS databases (restricted to articles in the English language posted between January 2000 and February 2007). The search terms 'CTLA-4Ig', 'abatacept' and 'ORENCIA' were used, and data from randomized clinical trials were summarized.

RESULTS

Abatacept provided clinically meaningful improvements in the signs and symptoms of RA in both MTX and TNF antagonist inadequate responders in Phase II and III studies. Health-related quality of life was also improved with abatacept, which demonstrated an acceptable safety and tolerability profile in both patient populations. Additionally, when assessed in patients with an inadequate response to MTX, abatacept inhibited structural damage progression.

CONCLUSION

Although longer-term data are required and differing study designs preclude direct comparisons with other RA therapies, results of clinical trials to date suggest that abatacept has an acceptable safety profile and is an effective treatment option for patients with RA, whether treating biologic-naïve patients or those who have already had an inadequate response to TNF antagonists.

Rheumatoid arthritis: strategies in the management of patients showing an inadequate response to TNFalpha antagonists

The introduction of medications that target specific proinflammatory cytokines has revolutionized the management of patients with rheumatoid arthritis. The agents that antagonize the effects of tumour necrosis factor (TNF)-alpha -- infliximab, etanercept and adalimumab -- have consistently shown very good efficacy for controlling the clinical and radiographic manifestations of the disease. However, it has become apparent that some patients will receive no clinical benefit, gradually lose the effect over time or experience adverse effects with the TNFalpha antagonists. The management of these patients is challenging and there are no clear guidelines. The concomitant administration of a disease-modifying antirheumatic drug, such as methotrexate, has been shown to improve outcomes. Optimization of the methotrexate or TNFalpha antagonist dose may lead to improved responses, as demonstrated in some dose escalation studies. Switching to another TNFalpha antagonist is a step that is supported by small, mostly uncontrolled studies. Finally, the T-cell co-stimulation antagonist abatacept, as well as the B-cell depleting agent rituximab, are also available for use in patients who have had an inadequate response or intolerance to the TNFalpha antagonists.Genotypic studies have identified TNF and TNF receptor polymorphisms that appear to predict independently whether a patient will respond to a TNFalpha antagonist, but genotyping is not available for routine use in clinical practice. Until such tools for predicting response are widely available, the management of patients with poor responses to TNFalpha antagonists will have to depend upon the wishes of the patient regarding medication dosage schedules and adverse effect profiles, as well as how comfortable the treating physician is with the available biological medications. In this article, we review the current data and construct an algorithm to help guide clinicians in the management of patients with inadequate responses to the TNFalpha antagonists.

The "T" in trauma: the helper T-cell response and the role of immunomodulation in trauma and burn patients

BACKGROUND

The immune system undergoes numerous changes after traumatic and burn injuries, including a down-regulation of the TH1 response and up-regulation of the TH2 response.

METHODS

The PubMed, Medline, and Ovid search engines were queried for relevant human studies. Bibliographies were also meticulously reviewed.

RESULTS

An interesting and potentially clinically relevant pattern of immune dysregulation exists after injury. The type 1 T-helper cell (TH1) response is suppressed as illustrated by diminished interleukin (IL)-2, interferon (IFN)-gamma, and IL-12 levels after major injury. The enhancement of the TH2 response is marked by elevated IL-10 and IL-4. Certain cytokine profiles, ratios, and polymorphisms may help identify patients at increased risk of systemic inflammatory response syndrome (SIRS), sepsis, multiple organ failure (MOF), and deep venous thrombosis. The most promising prognostic indicators to date are decreased production of the IL-12, elevated IL-10, soluble IL-2 receptor-a (sIL-2Ra), and IL-18 levels, IL-18 promoter polymorphisms, the IL-6:IL-10 ratio, and the degree of TH1 suppression as measured by diminished IL-2 and IFN-gamma. The Cytokine sections are subdivided into basic science, human studies, animal studies (when necessary), and directed therapeutics. The outcomes of sepsis, SIRS, or MOF are generally discussed together.

CONCLUSIONS

T-cell-specific immunologic changes occur after major injury. Identification of those TH1/TH2 cytokine profiles associated with worse prognosis may one day allow clinicians to risk stratify injured patients and identify those at increased risk of developing SIRS, sepsis, MOF, and deep venous thrombosis. Immune-targeted therapies may eventually serve as effective treatments in the acute setting to decrease morbidity and mortality, and to improve the management and prognosis of those patients at risk for developing postinjury complications.

Wen-Pi-Tang-Hab-Wu-Ling-San extract inhibits the release of inflammatory mediators from LPS-stimulated mouse macrophages

AIM OF THE STUDY

Wen-Pi-Tang is a traditional herbal prescription that has been used traditionally for the treatment of various inflammatory diseases, including chronic renal failure, renal injury, renal tubular cell damage and diabetic nephropathy. In this study, we investigated the pharmacological activity of modified Wen-Pi-Tang, Wen-Pi-Tang-Hab-Wu-Ling-San (WHW) extract.

MATERIALS AND METHODS

Production of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-6 and NO in supernatant, mRNA expression of TNF-alpha, IL-1beta, IL-6 and iNOS, protein expression of iNOS, phosphorylation of mitogen-activated protein kinases (MAPKs) and activation of nuclear factor-kappa B in the extract were assayed.

RESULTS

We found that WHW extract had potent anti-inflammatory effects in LPS-stimulated RAW264.7 cells and primary peritoneal macrophages. WHW extract strongly inhibited the excessive production of inflammatory mediators, nitric oxide (NO), TNF-alpha (TNF-alpha), interleukin 1-beta (IL-1beta) and IL-6 in LPS-stimulated macrophages. The inhibition of inducible nitric oxide synthase (iNOS) and these cytokines resulted from the reduced expressions of mRNAs of iNOS and these cytokines, respectively. WHW extract attenuated the phosphorylation of mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinases 1 and 2 (ERK1/2) and c-Jun N-terminal kinase (JNK), as well as the activation of nuclear factor-kappa B (NF-kappaB) in LPS-stimulated RAW264.7 cells.

CONCLUSIONS

These data suggest that WHW extract may exhibit anti-inflammatory effects through the modulation of MAPK and the NF-kappaB-dependent pathway involved in inflammation.

New antirheumatic drugs: any real added value? A critical overview of regulatory criteria for their marketing approval

OBJECTIVE

Rheumatoid arthritis (RA) is a systemic autoimmune disorder causing chronic polyarticular synovial inflammation and progressive joint damage. New anti-rheumatic drugs, such as leflunomide, infliximab, etanercept, adalimumab and anakinra, have recently become available. The aim of this paper is to summarize and critically evaluate the type of studies and clinical endpoints accepted by the European Medicines Agency (EMEA) to approve these new drugs.

MATERIALS AND METHODS

Information regarding the approval of antirheumatic drugs was obtained from European Public Assessment Reports (EPARs) and published pivotal studies.

RESULTS

Leflunomide is the only non-biological disease-modifying anti-rheumatic drug (DMARD) to receive recent approval for RA treatment, but strong evidence of its superiority over conventional therapies is lacking. Anakinra in combination with methotrexate received approval as a DMARD for RA on the basis of two pivotal trials in which American College of Rheumatology response criteria (ACR 20 response) were used as the sole primary endpoint. For easier demonstration of efficacy, studies leading to first approval of etanercept, infliximab and adalimumab were carried out on non-responders to DMARDs. Once on the market, these drugs gained an extension of the indication to methotrexate-naïve patients. Studies that provided the basis for approval were not adequately designed, given the lack of an active control and the choice of ACR response as the only clinical endpoint. Consequently, only a weak proof of efficacy emerged for the treatment of signs and symptoms of RA, and these drugs failed to show real benefit in slowing radiographic progression. Serious infections, changes in blood cell counts, severe skin and hepatic infections were the main adverse events that emerged from the clinical studies. Therefore, the unconvincing benefit of the new antirheumatic drugs can scarcely outweigh the risk associated with their use. Moreover, the monthly costs in Italy of the new biological preparations are several fold higher than those of the reference drugs.

CONCLUSIONS

Recently approved anti-RA products should be a therapeutic option only for patients refractory to conventional drugs.

Chronic rhinosinusitis and psoriasis: do mutually exclusive systemic Th1 and Th2 disease patterns exist?

CONCLUSION

Our results support the theory that chronic rhinosinusitis (CRS) is a systemic Th alteration, the relevance of which is discussed in detail.

OBJECTIVE

CRS imposes a heavy burden on society; however, a reliable CRS therapy has not been found. Developing a better understanding of this pathology will help us in our search for more effective therapies. One question, which is rarely examined, is the possibility of CRS existing as a systemic immune alteration in Th response. Thus, the goal of this study was to examine the occurrence of CRS, a Th2 pathology, with Th1 pathologies such as psoriasis.

PATIENTS AND METHODS

This study was performed via a retrospective electronic query of our medical center in regards to patients coded with the respective diagnosis.

RESULTS

Analysis of the data showed that occurrence of CRS rarely coincided with the occurrence of psoriasis and other such Th1 pathologies.

siRNA targeting PLK-1 induces apoptosis of synoviocytes in rheumatoid arthritis

Polo-like kinase-1 (PLK-1) is a member of the PLK family and participates in the control of cell mitosis. Here, we show that immunoreactive PLK-1 is strongly expressed in synoviocytes and some infiltrative mononuclear cells in synovial tissues from patients with rheumatoid arthritis (RA), while patients with osteoarthritis and injury show little or no expression of PLK-1 in synovial tissues. Western blot analysis shows that PLK is expressed and its expression is enhanced by IL-1beta in RA synoviocytes. IL-1beta also enhanced the cell growth of RA synoviocytes. Moreover, siRNA targeted against PLK-1 significantly decreases the expression of PLK-1 of RA synoviocytes stimulated by IL-1beta and suppresses the proliferation of these synoviocytes through apoptosis. These findings suggest that PLK-1 plays a critical role in the proliferation of RA synoviocytes leading to bone destruction, and siRNA against PLK-1 is potentially useful for the treatment of RA.

PLCgamma2 regulates osteoclastogenesis via its interaction with ITAM proteins and GAB2

Excessive bone loss in arthritic diseases is mostly due to abnormal activation of the immune system leading to stimulation of osteoclasts. While phospholipase Cgamma (PLCgamma) isoforms are known modulators of T and B lymphocyte-mediated immune responses, we found that blockade of PLCgamma enzymatic activity also blocks early osteoclast development and function. Importantly, targeted deletion of Plcg2 in mice led to an osteopetrotic phenotype. PLCgamma2, independent of PLCgamma1, was required for receptor activator of NF-kappaB ligand-induced (RANKL-induced) osteoclastogenesis by differentially regulating nuclear factor of activated T cells c1 (NFATc1), activator protein-1 (AP1), and NF-kappaB. Specifically, we show that NFATc1 upregulation is dependent on RANKL-mediated phosphorylation of PLCgamma2 downstream of Dap12/Fc receptor gamma (Dap12/FcRgamma) receptors and is blocked by the PLCgamma inhibitor U73122. In contrast, activation of JNK and NF-kappaB was not affected by U73122 or Dap12/FcRgamma deletion. Interestingly, we found that in osteoclasts, PLCgamma2 formed a complex with the regulatory adapter molecule GAB2, was required for GAB2 phosphorylation, and modulated GAB2 recruitment to RANK. Thus, PLCgamma2 mediates RANKL-induced osteoclastogenesis and is a potential candidate for antiresorptive therapy.

Use of biologics in rheumatoid arthritis: Where are we going?

PURPOSE

The pharmacology, efficacy, safety, and costs of biologic agents that are approved by the Food and Drug Administration or are under review for the management of rheumatoid arthritis (RA) are discussed. Biologic therapies that are currently under investigation in early- and late-phase clinical trials are summarized at the end of this report.

SUMMARY

The use of biologic agents for the treatment of RA has significantly improved the management of this disease. Experimental and clinical studies have shown that these agents ameliorate the signs and symptoms of RA, slow radiographic progression of disease, and improve physical function and quality of life. Data also support that early initiation of therapy with these agents improves long-term outcomes. However, biologic agents are associated with adverse effects that health care providers need to recognize and manage.

CONCLUSION

Biologic agents have revolutionized the treatment of RA by reducing the signs and symptoms of RA, slowing radiographic progression of joint destruction, and improving physical function and quality of life in affected patients.

Immunologic mechanisms in the pathogenesis of rheumatoid arthritis

Although much is known about the etiology and pathogenesis of rheumatoid arthritis (RA), our understanding of the immune pathways remains incomplete. The observed clinical and pathologic manifestations result from activation of several interrelated immune pathways. Current concepts of RA pathogenesis, supported by animal models, laboratory studies, and clinical observation, have reestablished and revised some of the original views. Early proposals emphasized the importance of autoantibodies and immune complexes in the initiation of RA, suggested a role for T cells in the inflammatory response characteristic of RA, and based disease perpetuation on an imbalance in the cytokine networks. We now recognize that each of these interrelated mechanisms significantly contributes to RA pathogenesis, including T cells that can help initiate and perpetuate the disease. This article reviews the major components and immune pathways involved in RA and briefly discusses the animal models that contribute to our understanding. Although a unified theory of RA pathogenesis may not be possible at this time, a paradigm is presented that considers the immune pathways that contribute to disease progression and joint destruction. These pathways may have important implications for treatment, because their modulation by biologic response modifiers (BRMs) directed toward specific targets provides benefits to patients with RA. BRMs are a new class of therapeutic agents derived from biologically active molecules and designed to modulate specific immune or inflammatory pathways. Although currently approved BRMs still have limitations, choosing an appropriate target, possibly early rather than late in the immune response, might result in new and improved therapies for RA.