Immune function in patients with rheumatoid arthritis treated with etanercept

A novel intergenic variant, rs2004339 A/G, of the gene encoding interleukin-40, C17orf99, is associated with risk of rheumatoid arthritis in Iraqi women

Interleukin-40 (IL-40) is a novel cytokine encoded by the chromosome 17 open reading frame 99 (C17orf99) gene. Recent studies have shown that IL-40 levels are significantly up-regulated in patients with rheumatoid arthritis (RA). However, the association of genetic variants of the C17orf99 gene with the risk of RA has not been investigated. In this case-control study, two intergenic variants, rs2004339 A/G and rs2310998 G/A, were genotyped for the first time in 120 Iraqi women with RA (30 newly diagnosed [ND] and 90 medicated [MD; treated with the tumor necrosis inhibitor etanercept plus methotrexate]) and 110 control women using TaqMan 5'-allele discrimination method. Serum IL-40 levels were also determined using an enzyme-linked immunosorbent assay kit. Multinomial logistic regression analysis was used to analyze rs2004339 and rs2310998 under five genetic models (allele, recessive, dominant, over-dominant, and co-dominant). Results revealed that the mutant A allele (allele model) and the homozygous AA genotype (co-dominant model) of rs2004339 were significantly associated with an increased risk of RA (odds ratio [OR] = 3.37 and 7.44, respectively; corrected probability [pc] < 0.001), while rs2310998 showed no association with RA risk. When comparing the allele and genotype frequencies of rs2004339 and rs2310998 between ND and MD patients, there were no statistically significant differences. Haplotype analysis of the two variants (in the order rs2004339-rs2310998) revealed that haplotypes A-A (OR = 1.72; pc = 0.024) and A-G (OR = 2.85; pc < 0.001) were associated with an increased risk of RA. IL-40 levels (median and interquartile range) were significantly elevated in RA patients compared to controls (29.3 [15.5-41.5] vs. 12.6 [7.4-18.8] pg/mL; p < 0.001). IL-40 levels were not influence by disease duration or disease activity, but the rs2310998 genotypes had an effect; IL-40 levels were significantly higher in women with the AA genotype than in women with the GG genotype (20.1 [12.9-37.1] vs. 15.8 [8.3-22.6] pg/mL; p = 0.006). Regarding medication, IL-40 tended to show elevated levels in ND cases compared to MD cases but without a significant difference. In conclusion, the mutant A allele and the mutant-type AA genotype of the intergenic variant rs2004339 were associated with an increased risk of RA among Iraqi women. Serum IL-40 levels were also elevated in patients, particularly ND patients, and were positively affected by the mutant-type AA genotype. Accordingly, the role of IL-40 in the pathogenesis of RA has been indicated.

Efficacy of HDAC inhibitors and epigenetic modulation in the amelioration of synovial inflammation, cellular invasion, and bone erosion in rheumatoid arthritis pathogenesis

Rheumatoid arthritis (RA), an auto-immune disorder affected 1 % of the population around the globe. The pathophysiology of RA is highly concerted process including synovial hyperplasia, pannus formation, bone erosion, synovial cell infiltration in joints, and cartilage destruction. However, recent reports suggest that epigenetics play a pivotal role in the formation and organization of immune response in RA. Particularly, altered DNA methylation and impaired microRNA (miRNA) were detected in several immune cells of RA patients, such as T regulatory cells, fibroblast-like synoviocytes, and blood mononuclear cells. All these processes can be reversed by regulating the ubiquitous or tissue-based expression of histone deacetylases (HDACs) to counteract and terminate them. Hence, HDAC inhibitors (HDACi) could serve as highly potent anti-inflammatory regulators in the uniform amelioration of inflammation. Therefore, this review encompasses the information mainly focussing on the epigenetic modulation in RA pathogenesis and the efficacy of HDACi as an alternative therapeutic option for RA treatment. Overall, these studies have reported the targeting of HDAC1, 2 & 6 molecules would attenuate synoviocyte inflammation, cellular invasion, and bone erosion. Further, the inhibitors such as trichostatin A, suberoyl bis-hydroxamic acid, suberoyl anilide hydroxamic acid, and other compounds are found to attenuate synovial inflammatory immune response, clinical arthritis score, paw swelling, bone erosion, and cartilage destruction. Insight to view this, more clinical studies are required to determine the efficacy of HDACi in RA treatment and to unravel the underlying molecular mechanisms.

Novel aspects of the activation of NADPH oxidase in neutrophils of rheumatic patients on biological therapy

The relationship between inflammation and formation of reactive oxygen species (ROS) is still not completely understood and excessive inflammatory reaction is attributed to increased yet also to reduced ROS formation. To compare ROS formation in severe and low inflammation, neutrophil oxidative burst was analyzed in rheumatic patients before and during therapy with TNFα- or interleukin-6 receptor-neutralizing antibodies. Intracellular and extracellular ROS productions were evaluated on the basis of luminol- and isoluminol-enhanced chemiluminescence in isolated peripheral neutrophils. Disease activity score DAS28 and platelet to lymphocyte ratio were used as markers of arthritis activity and the intensity of systemic inflammation. Biological therapy effectively reduced the intensity of inflammation. Of the twenty-six patients studied eighteen achieved remission or low disease activity. Highly active arthritis persisted only in one patient, though prior to the therapy it was evident in all subjects tested. In patients receiving biological therapy, intracellular chemiluminescence was significantly higher than in patients before this therapy; ROS produced by neutrophils extracellularly were not affected. The increased ROS formation associated with reduced inflammation supports the need to revise the view of the role of ROS in inflammation - from toxic agents promoting inflammation towards a more complex view of ROS as regulators of immune pathways with inflammation-limiting capacity. From this perspective, the interference with neutrophil-derived oxidants may represent a new mechanism involved in the anti-inflammatory activity of biological therapy.

Increased intracellular and extracellular oxidant production in phagocytes of rheumatic patients treated with biological therapy - whole blood quantification

Infectious complications, resulting from reduced activity of immune cells, are the most severe and common adverse effects of biological therapy. This study analyzed the effect of biological therapy on blood phagocytes, focusing on the formation of reactive oxygen species (ROS), an important factor in the defence against invading pathogens. Intra- and extracellular ROS production were recorded separately, on the basis of luminol and isoluminol chemiluminescence in patients treated with antibodies against tumor necrosis factor-α or against interleukin-6 receptor. In comparison to healthy donors or to rheumatic patients treated with classical immunosuppressive drugs, biological therapy increased ROS formation in both compartments. This indicates that the anti-microbial activity of blood phagocytes was not reduced by TNFα- or IL-6-neutralizing therapy, at least in terms of ROS.

The method presented does not require blood fractionation, which could modify activity of phagocytes and cause loss of some subpopulations of these cells. The technique is simple, requires microliter volumes of blood and is thus well applicable to clinical studies.

Changes in T cell effector functions over an 8-year period with TNF antagonists in patients with chronic inflammatory rheumatic diseases

The aim of the study was to clarify the effect of long-term anti-TNF therapy on T cell function in patients with rheumatologic immune-mediated inflammatory diseases (IMID). The production of IFNγ by T cells was evaluated at baseline and after 1, 2, 4, and 8 years of anti-TNF agents by means of a QuantiFERON-TB Gold In-Tube assay. The T cell proliferation and surface co-expression of CD25/CD134 in response to phytohaemagglutinin together with the in vitro impact of anti-TNF therapy on the functional capacity of T cells were evaluated after 8 years from the onset of the biological treatment. Age-matched healthy donors were enrolled as controls. The quantitative mitogen-induced IFNγ responses significantly increased with respect to baseline at each time point, apart from the determination after 4 years. We found an increased expression of CD25/CD134 in CD4⁺ compared to CD8⁺ T cells both in patients and controls. The in vitro addition of anti-TNF agents induced a significant decrease of both the IFNγ response and of CD25/CD134, whereas no effect on the intensity of the proliferative response was observed. Our data provide a biological basis for the reassuring issues on the safety of long-term anti-TNF treatment in patients with IMID.

Effect of Tumor Necrosis Factor Inhibitor Therapy on Osteoclasts Precursors in Rheumatoid Arthritis

Objective. Tumor necrosis factor (TNF) increases circulating osteoclast (OC) precursors numbers by promoting their proliferation and differentiation. The aim of this study was to assess the effect of TNF inhibitors (TNFi) on the differentiation and activity of OC in rheumatoid arthritis (RA) patients. Methods. Seventeen RA patients treated with TNFi were analyzed at baseline and after a minimum follow-up period of 6 months. Blood samples were collected to assess receptor activator of nuclear factor kappa-B ligand (RANKL) surface expression on circulating leukocytes and frequency and phenotype of monocyte subpopulations. Quantification of serum levels of bone turnover markers, in vitro OC differentiation assays, and qRT-PCR for OC specific genes was performed. Results. After TNFi therapy, patients had reduced RANKL surface expression in B-lymphocytes and the frequency of circulating classical CD14^brightCD16⁻ monocytes was decreased. Serum levels of sRANKL, sRANKL/OPG ratio, and CTX-I were reduced in RA patients after TNFi treatment. Moreover, after exposure to TNFi, osteoclast differentiation and activity were decreased, as well as the expression of TRAF6 and cathepsin K. Conclusion. We propose that TNFi arrests bone loss and erosion, through two pathways: direct reduction of osteoclast precursor numbers and inhibition of intracellular signaling pathways acting through TRAF6.

Characterisation of the clinical and activated T cell response to repeat delayed-type hypersensitivity skin challenges in human subjects, with KLH and PPD, as a potential model to test T cell-targeted therapies

OBJECTIVE

To characterise the delayed-type hypersensitivity (DTH) skin reaction to repeated challenges of keyhole limpet hemocyanin (KLH) and tuberculin purified protein derivative (PPD) in healthy volunteers, as a potential model to test T cell-targeted investigational agents.

SUBJECTS, TREATMENT AND METHODS

Forty-nine subjects received either KLH, PPD, or PBS repeat skin challenges, and clinical assessments including induration, erythema and Laser Doppler Imaging. Skin biopsies or suction blisters were taken after challenge to investigate the cellular infiltrate of the challenge site, the T cell activation status, as determined by LAG-3 expression, and, specifically for the blister, the concentrations of inflammatory cytokines. Point estimates, estimates of variation and corresponding 95% confidence intervals were constructed for each type of challenge and timepoint.

RESULTS

The DTH response could be measured at 48 and 120 h post-KLH and PPD challenge with induration, erythema and Laser Doppler Imaging, with 48 h post-challenge demonstrating the peak of the response. PPD was well tolerated in subjects after multiple challenges, however, a significant number of KLH-treated subjects demonstrated an injection site reaction 6-7 days following the SC injection. PPD demonstrated a boost effect on the second challenge as measured by increased induration, where as this was not noted consistently for KLH. Compared to unchallenged and PBS control-injected skin, increased T cell numbers were detected in the challenge site by both the skin suction blister and biopsy technique, at either time point following KLH or PPD challenge. Use of the T cell activation marker LAG-3 demonstrated the activated phenotype of these cells. In skin blisters, higher numbers of LAG-3+ T cells were detected at 48 h post-challenge, whereas in the biopsies, similar numbers of LAG-3+ cells were observed at both 48 and 120 h. Analysis of blister T cell subpopulations revealed some differences in phenotypes between the time points and between the CD4 and CD8 T cells. Blister cytokine analysis revealed a pro-inflammatory dominated signature in PPD-challenged skin.

CONCLUSIONS

In summary, our data support the use of a repeat KLH and PPD DTH challenge in clinical trials and that the clinical measures of induration and to a lesser extent erythema are appropriate to monitor the clinical DTH response. Both the blister and biopsy can be utilised to assess and quantify activated T cells and at the dose used, PPD was better tolerated than KLH and hence may be optimal for future studies.

Effects of biological and non-biological immunomodulatory therapies on the immunogenicity of vaccines in patients with rheumatic diseases

Vaccinations are administered to patients to induce a protective immune response, resulting in immunological memory. Preventing infection through the use of vaccines is particularly important in immunocompromised and immunosuppressed individuals given their increased frequency and severity of infections relative to healthy individuals. Recent surveys show that the vaccination rate is still alarmingly low in patients with rheumatic disease. In this review we briefly discuss the different types of vaccines and then critically examine evidence related to vaccination efficacy in patients with autoimmune disease and the effects of immunomodulatory therapy, with an aim to provide guidance and optimize the administration of vaccines in such individuals.

The comparative safety of tumor necrosis factor inhibitors in rheumatoid arthritis: a meta-analysis update of 44 trials

OBJECTIVE

The study objective was to evaluate and update the safety data from randomized controlled trials of tumor necrosis factor inhibitors in patients treated for rheumatoid arthritis.

METHODS

A systematic literature search was conducted from 1990 to May 2013. All studies included were randomized, double-blind, controlled trials of patients with rheumatoid arthritis that evaluated adalimumab, certolizumab pegol, etanercept, golimumab, or infliximab treatment. The serious adverse events and discontinuation rates were abstracted, and risk estimates were calculated by Peto odds ratios (ORs).

RESULTS

Forty-four randomized controlled trials involving 11,700 subjects receiving tumor necrosis factor inhibitors and 5901 subjects receiving placebo or traditional disease-modifying antirheumatic drugs were included. Tumor necrosis factor inhibitor treatment as a group was associated with a higher risk of serious infection (OR, 1.42; 95% confidence interval [CI], 1.13-1.78) and treatment discontinuation due to adverse events (OR, 1.23; 95% CI, 1.06-1.43) compared with placebo and traditional disease-modifying antirheumatic drug treatments. Specifically, patients taking adalimumab, certolizumab pegol, and infliximab had an increased risk of serious infection (OR, 1.69, 1.98, and 1.63, respectively) and showed an increased risk of discontinuation due to adverse events (OR, 1.38, 1.67, and 2.04, respectively). In contrast, patients taking etanercept had a decreased risk of discontinuation due to adverse events (OR, 0.72; 95% CI, 0.55-0.93). Although ORs for malignancy varied across the different tumor necrosis factor inhibitors, none reached statistical significance.

CONCLUSIONS

These meta-analysis updates of the comparative safety of tumor necrosis factor inhibitors suggest a higher risk of serious infection associated with adalimumab, certolizumab pegol, and infliximab, which seems to contribute to higher rates of discontinuation. In contrast, etanercept use showed a lower rate of discontinuation. These data may help guide clinical comparative decision making in the management of rheumatoid arthritis.

Restoration of peripheral blood natural killer and B cell levels in patients affected by rheumatoid and psoriatic arthritis during etanercept treatment

Etanercept (ETN) is an anti-tumour necrosis factor (TNF)-α agent used in rheumatoid arthritis (RA) and psoriatic arthritis (PsA). Few studies focused on the effects of anti-TNF-α on peripheral blood cells. We aimed to evaluate peripheral blood cells in RA and PsA patients during ETN treatment and to explore their relationships with disease activity. RA (n = 82) and PsA (n = 32) patients who started ETN were included into the study and evaluated prospectively before the beginning of ETN therapy and after 14, 22, 54 and 102 weeks. Patients were studied in terms of disease activity score on 28 joints (DAS28), clinical response and laboratory findings. Natural killer (NK) cells, B cells and T cells were characterized by immunophenotyping. Both the RA and the PsA patients showed reduced NK and B cell count before ETN treatment compared with controls. A negative correlation was demonstrated between DAS28 and B cell count in RA patients at baseline. Sustained significant increase of NK and B cells up to normal levels was observed in RA and PsA patients along ETN treatment. Increase of NK cell count was associated with a good-moderate clinical response to ETN in both RA and PsA patients. During ETN treatment peripheral blood NK and B cells levels were restored in RA and PsA patients. Correlations between NK and B cells with disease activity were observed, suggesting that those effects could be mediated by ETN treatment.

Apoptosis as a mechanism of action of tumor necrosis factor antagonists in rheumatoid arthritis

Tumor necrosis factor (TNF) antagonists are drugs developed to block endogenous TNF, an essential proinflammatory molecule with a central role in the pathogenesis of rheumatoid arthritis (RA). Although extensive studies have been performed concerning the mode of action of TNF-blocking agents, there are still many unresolved questions and potential differences between different TNF-blocking drugs. One unresolved issue is to what extent apoptosis is affected by TNF blockade in RA. We provide an overview of studies that have investigated the proapoptotic effect of different anti-TNF drugs in RA, searching for a unified interpretation of somewhat contradictory data.

Etanercept in the treatment of rheumatoid arthritis

Etanercept (ETN) is the first anti-tumor necrosis factor (TNF) agent to be approved for the treatment of rheumatoid arthritis (RA). Over the last 8 years, several clinical trials have shown its efficacy and safety in established and early RA, as well as a monotherapy or in combination with methotrexate. ETN not only reduces the signs and symptoms of RA, but also retards the progression of radiographic damage and improves the quality of life and function of patients. Its safety profile has been predictable since the first clinical trials with no new major safety concerns. Beyond its efficacy in RA, ETN is also indicated for the treatment of psoriatic arthritis. This current report reviews the evidence and the data in RA and psoriatic arthritis (PsA).

Fungal infections complicating tumor necrosis factor alpha blockade therapy

Tumor necrosis factor a (TNF-alpha) blockade has emerged as a useful therapy for collagen vascular diseases or graft-vs-host disease. Fungal infections complicating such therapy have been reported sporadically. MEDLINE and PubMed databases (from January 1, 1966, to June 1, 2007) were searched for reports of invasive fungal infections (IFIs) associated with the 3 available anti-TNF- alpha agents, ie, infliximab, etanercept, and adalimumab. Of the 281 cases of IFI associated with TNF-alpha inhibition, 226 (80%) were associated with infliximab, 44 (16%) with etanercept, and 11 (4%) with adalimumab. Fungal infections associated with infliximab occurred a median of 55 days (interquartile range [IQR], 15-140 days) after initiation of therapy and 3 infusions of the medication (IQR, 2-5), whereas those associated with etanercept occurred a median of 144 days (IQR, 46-240 days) after initiation of therapy. The median age of patients was 58 years (IQR, 44-68 years), and 62% were male. Use of at least 1 other immunosuppressant medication, typically a systemic corticosteroid, was reported during the course of the fungal infection in 102 (98%) of the 104 patients for whom data were available. The most prevalent IFIs were histoplasmosis (n=84 [30%]), candidiasis (n=64 [23%]), and aspergillosis (n equals 64 [23%]). Pneumonia was the most common pattern of infection. Of the 90 (32%) of 281 cases for which outcome information was available, 29 fatalities (32%) were recorded. Tumor necrosis factor a blockade is associated with IFI across a range of host groups. A high index of suspicion in patients treated with TNF-alpha antagonists is recommended because the course of such infections can be serious or fulminant, and rapid access to health care should be provided. Surveillance of IFIs complicating TNF-alpha blockade and other biologic therapies is warranted through well-organized prospective patient registries.

Mechanism of action of certolizumab pegol (CDP870): in vitro comparison with other anti-tumor necrosis factor alpha agents

BACKGROUND

Inhibitors of tumor necrosis factor alpha (TNFalpha) have demonstrated significant efficacy in chronic inflammatory diseases, including Crohn's disease (CD). To further elucidate the mechanisms of action of these agents, we compared the anti-TNFalpha agents certolizumab pegol, infliximab, adalimumab, and etanercept in several in vitro systems.

METHODS

The ability of each anti-TNFalpha agent to neutralize soluble and membrane-bound TNFalpha; mediate cytotoxicity, affect apoptosis of activated human peripheral blood lymphocytes and monocytes; induce degranulation of human peripheral blood granulocytes, and modulate lipopolysaccharide (LPS)-induced interleukin (IL)-1beta production by human monocytes was measured in vitro.

RESULTS

All 4 agents neutralized soluble TNFalpha and bound to and neutralized membrane TNFalpha. Infliximab and adalimumab were comparable in their ability to mediate complement-dependent cytotoxicity and antibody-dependent cell-mediated cytotoxicity, and to increase the proportion of cells undergoing apoptosis and the level of granulocyte degranulation. Etanercept generally mediated these effects to a lesser degree, while certolizumab pegol gave similar results to the control reagents. LPS-induced IL-1beta production was inhibited by certolizumab pegol, infliximab, and adalimumab, but only partially inhibited by etanercept.

CONCLUSIONS

In contrast to the other anti-TNFalpha agents tested, certolizumab pegol did not mediate increased levels of apoptosis in any of the in vitro assays used, suggesting that these mechanisms are not essential for the efficacy of anti-TNFalpha agents in CD. As certolizumab pegol, infliximab, and adalimumab, but not etanercept, almost completely inhibited LPS-induced IL-1beta release from monocytes, inhibition of cytokine production may be important for efficacy of anti-TNFalpha agents in CD.

Tumor necrosis factor antagonist mechanisms of action: a comprehensive review

During the past 30 years, elucidation of the pathogenesis of rheumatoid arthritis, Crohn's disease, psoriasis, psoriatic arthritis and ankylosing spondylitis at the cellular and molecular levels has revealed that these diseases share common mechanisms and are more closely related than was previously recognized. Research on the complex biology of tumor necrosis factor (TNF) has uncovered many mechanisms and pathways by which TNF may be involved in the pathogenesis of these diseases. There are 3 TNF antagonists currently available: adalimumab, a fully human monoclonal antibody; etanercept, a soluble receptor construct; and infliximab, a chimeric monoclonal antibody. Two other TNF antagonists, certolizumab and golimumab, are in clinical development. The remarkable efficacy of TNF antagonists in these diseases places TNF in the center of our understanding of the pathogenesis of many immune-mediated inflammatory diseases. The purpose of this review is to discuss the biology of TNF and related family members in the context of the potential mechanisms of action of TNF antagonists in a variety of immune-mediated inflammatory diseases. Possible mechanistic differences between TNF antagonists are addressed with regard to their efficacy and safety profiles.

Wound healing complications and infection following surgery for rheumatoid arthritis

The goal of the foot and ankle surgeon is to achieve balanced correction of deformity in patients who have rheumatoid arthritis (RA) while minimizing the risk for complications. To achieve these goals, a large number of procedures may be required at a single or in a staged operative setting. In this article, the evaluation of the patient to assess operative risks and the management of perioperative complications in the RA foot and ankle patient are presented.

Safety of etanercept therapy in rheumatoid patients undergoing surgery: preliminary report

This is a preliminary report on a case-series of rheumatoid patients that underwent various kinds of elective surgery but did not withdraw etanercept therapy in spite of physician advise. Elective surgery consisted of right knee surgical prosthesis, bilateral cataract, bilateral hallux valgus, right hip prosthesis, bladder stone by cystoscopy and left inguinal hernia. All the patients had a regular healing rate. During follow-up (6-12 months) no one of these patients were suffering from infective complications after surgery. According to same recent literature results, our data suggest that it is the time to value rheumatoid patient preferences through a correct information about cost-benefit of this treatment to establish together with patients if etanercept therapy has to be discontinued before and after elective surgery. Finally, we think that adverse drug reaction surveillance has to be boosted, and editors of leading scientific journal should publish more papers on case-series about drug safety and tolerability in particular conditions.

Influence of methotrexate, TNF blockers and prednisolone on antibody responses to pneumococcal polysaccharide vaccine in patients with rheumatoid arthritis

OBJECTIVE

To compare antibody responses to 23-valent pneumococcal vaccine (Pneumovax) in controls and patients with established rheumatoid arthritis (RA) treated with TNF blockers, methotrexate (MTX) or a combination of both.

METHODS

Patients with RA (n = 149) and healthy controls (n = 47) were vaccinated. Treatment with TNF blockers (etanercept or infliximab) and MTX was given to 50 patients, and 62 patients were treated with TNF blockers alone or with other DMARDs. MTX alone was given to 37 patients. Concentrations of immunoglobulin G (IgG) antibodies against pneumococcal capsular polysaccharides 23F and 6B were measured by enzyme-linked immunoassay before and 4-6 weeks after vaccination. An immune response was defined as a twofold or higher increase in antibody concentration following vaccination.

RESULTS

Prevaccination antibody levels for both 23F and 6B were similar in the patient groups. Antibody concentrations after vaccination increased significantly in all groups. Patients treated with TNF blockers without MTX showed better immune responses than those treated with TNF blockers in combination with MTX (P = 0.037 for 23F and P = 0.004 for 6B) or MTX alone (P<0.001 for both 23F and 6B). RA patients given MTX alone had the lowest immune responses. Prednisolone treatment did not influence the responses.

CONCLUSIONS

Patients treated with TNF blockers and controls showed similar responses to vaccination. In contrast, patients treated with MTX had reduced responses regardless of anti-TNF treatment. The findings do not argue against the use of pneumococcal vaccination in RA patients undergoing treatment with TNF blockers.

Blockade of tumour necrosis factor {alpha} significantly alters the serum level of IgG- and IgA-rheumatoid factor in patients with rheumatoid arthritis

OBJECTIVE

To determine the effect on the humoral immune system of long term treatment of patients with RA with etanercept.

METHODS

12 consecutive patients with seropositive RA treated with etanercept were studied and followed up for 9 months. Clinical efficacy of treatment was evaluated using the 28 joint count Disease Activity Score (DAS28). Serum samples were collected at baseline and after 9 months and serum immunoglobulin, RF isotypes, and anti-cyclic citrullinated peptide (aCCP), antinuclear, nucleosome, and dsDNA antibodies determined. For comparison 7 patients with seropositive RA treated with adalimumab were studied.

RESULTS

DAS28 decreased significantly after the first month and then was constant for the whole study (5.7 (0.3) v 3.8 (0.2), p< or=0.000). Serum IgA-RF and IgG-RF increased significantly after 9 months' etanercept treatment (mean (SEM) IgA-RF rose from 19.5 (4.8) to 30.5 (5.9) IU/ml, p< or=0.01; IgG-RF from 20.6 (8.1) to 33.8 (11.5) IU/ml, p< or=0.04). Serum levels of total immunoglobulin and specific autoantibodies remained unchanged during the study. In patients treated with adalimumab, no significant changes in serum levels of RF isotypes and aCCP antibodies were seen.

CONCLUSION

Etanercept, although effective in treating the clinical symptoms of RA, seems to have a pivotal effect on RF-producing B cells either directly or indirectly.

Blockade of TNF does not alter oxygen burst and phagocytosis of human neutrophils in patients with rheumatoid arthritis

Clinical trials evaluating tumor necrosis factor alpha (TNF-alpha) binding agents in patients with rheumatoid arthritis (RA) have demonstrated significant efficacy in reducing symptoms of disease and slowing radiographic progression. However, infectious complications are the most severe and common adverse effects of anti-TNF therapy. The functional capacities of neutrophils (PMNs) as the first line of defense in bacterial and fungal infections are enhanced by soluble TNF as a potent neutrophil primer. The aim of this study was to assess the influence of in vivo TNF blockade on oxygen burst (OB) and phagocytosis of human neutrophils. PMNs were derived from 20 patients with RA on anti-TNF-alpha therapy and 13 patients using conventional DMARDs. By flow cytometry we measured OB upon stimulation with Escherichia coli and N-formyl-1-methionyl-1-leucyl-phenylalanine (FMLP) with and without priming with granulocyte-colony stimulating factor (G-CSF) and/or TNF-alpha using dihydrorhodamine (DHR) 123. Phagocytosis of fluorescein isothiocyanate (FITC)-labeled E. coli was also assessed by flow cytometry. Thirty-three healthy volunteers served as controls. Upon stimulation with E. coli and FMLP, there was no significant difference in OB between the two patient groups and healthy controls. Priming was effective in all groups. Phagocytosis of E. coli by PMNs was equally effective in controls and patients independent from the treatment regimen. These data show that OB, phagocytosis and responsiveness to priming with TNF and G-CSF of PMNs are not impaired in patients with RA treated with anti-TNF agents in comparison with patients on conventional DMARDs or healthy controls. Thus, the infectious complications observed in patients with TNF blockade cannot be explained by functional impairment of PMNs; however, the neutralization of TNF as a potent primer of neutrophil response may increase the susceptibility for infections in these patients.

Effect of adalimumab on neutrophil function in patients with rheumatoid arthritis

Neutrophils are known to be targets for the biological activity of tumour necrosis factor (TNF)-alpha in the pathogenesis of rheumatoid arthritis (RA). Therefore, these cells may be among the targets of anti-TNF-alpha therapy. In this study we evaluated the effect of therapy with adalimumab (a fully human anti-TNF-alpha mAb; dosage: 40 mg subcutaneously every other week) on certain phenotypic and functional aspects of neutrophils obtained from 10 selected patients with RA and 20 healthy control individuals. Peripheral blood neutrophils were obtained at baseline and during anti-TNF-alpha therapy (2, 6 and 12 weeks after the first administration of adalimumab). All patients had been receiving a stable regimen of hydroxychloroquine, methotrexate and prednisone for at least 3 months before and during the study. Baseline neutrophil chemotaxis was significantly decreased in RA patients when compared with control individuals (P < 0.001). Two weeks after the first administration of adalimumab, chemotactic activity was completely restored, with no differences noted between patients and control individuals; these normal values were confirmed 6 and 12 weeks after the start of anti-TNF-alpha therapy. Phagocytic activity and CD11b membrane expression on neutrophils were similar between RA patients and control individuals; no modifications were observed during TNF-alpha neutralization. The production of reactive oxygen species, both in resting and PMA (phorbol 12-myristate 13-acetate)-stimulated cells, was significantly higher in RA patients at baseline (P < 0.05) and was unmodified by anti-TNF-alpha mAb. Finally, we showed that the activation antigen CD69, which was absent on control neutrophils, was significantly expressed on neutrophils from RA patients at baseline (P < 0.001, versus control individuals); however, the molecule was barely detectable on cells obtained from RA patients during adalimumab therapy. Because CD69 potentially plays a role in the pathogenesis of arthritis, our findings suggest that neutrophils are among the targets of anti-TNF-alpha activity in RA and may provide an insight into a new and interesting mechanism of action of anti-TNF-alpha mAbs in the control of inflammatory arthritis.

Infectious complications of treatment with biologic agents

PURPOSE OF REVIEW

There are three tumor necrosis factor-alpha inhibitors on the US and European markets today, and uncommon but devastating infectious complications accompany their use. This review describes the most important pathogen-specific infections and their relative frequency. Recent literature is summarized that has helped elucidate the pathophysiologic basis for their occurrence. Finally, evolving sets of recommendations for prevention, diagnosis, and treatment of infectious complications of their use are explored.

RECENT FINDINGS

Tuberculosis has continued to be the most common pathogen reported in association with infliximab, and less so with etanercept and adalimumab. Determining treated population case rates depends on having an accurate denominator and reflects the local population's latent infection rate. The same is true for histoplasmosis. Other pathogens requiring intact cellular immunity for control of latent infection have also been reported. Specific recommendations for preventive therapy are being made, but prospective clinical trials are needed to assess the risk-benefit of any particular approach.

SUMMARY

Microorganisms responsible for the infectious complications associated with anticytokine therapy are generally intracellular pathogens or pathogens that commonly exist in a chronic, latent state and are normally held in check by cell-mediated immunity. Diagnosis requires a high index of suspicion and prompt acquisition of appropriate tissue for microscopic examination and microbiologic culture. Prompt empiric therapy that focuses on the most likely infections is necessary to prevent mortality.

Crohn's disease: future anti-tumor necrosis factor therapies beyond infliximab

The dramatic benefit experienced by many Crohn's disease patients treated with the anti-tumor necrosis factor-alpha (TNF-alpha) antibody infliximab underscores the centrality of this cytokine in the pathogenesis of Crohn's disease and the potential use of the therapeutic strategy of blocking TNF-alpha in this disease. In the hopes of emulating and improving on the success of infliximab, numerous strategies are being devised and studied to inhibit the actions of TNF-alpha. This article focuses on those agents, other than infliximab, which target TNF-alpha to treat inflammatory bowel disease as their central mechanism of action.

The usefulness and the limitations of animal models in identifying targets for therapy in arthritis

Animal models have played a critical role in the history of modern drug development for rheumatoid arthritis (RA). In this chapter I examine the contributions of animal models in arthritis therapy from adjuvant arthritis and COX-1 inhibitors to transgenic mice and biological response modifiers. Advances in knowledge of the mechanisms of connective tissue disease are frequently derived from the study of animal models, and these findings frequently identify therapeutic targets that are subsequently evaluated in animal models. Hence a critical relationship between insights into the pathology of arthritis and the development of novel therapeutic approaches exists around the study of animal models of arthritis. In particular, we examine how the study of collagen-induced arthritis in rodents led to pioneering work in cytokine inhibitors for the successful therapy of RA.

Infectious and healing complications after elective orthopaedic foot and ankle surgery during tumor necrosis factor-alpha inhibition therapy

BACKGROUND

Biologic response modifiers are assuming a larger role in the management of patients with rheumatoid arthritis. The tumor necrosis factor-alpha (TNF-alpha) inhibitors etanercept and infliximab improve patient symptoms and function. However, these agents have been associated with a risk for healing and infectious complications due to systemic blockade of TNF-alpha, a ubiquitous mediator required in the normal inflammatory response in tissue healing and infection surveillance. This study analyzed the risk of healing/infectious complications in patients undergoing elective foot and ankle surgery while being treated with TNF-alpha inhibitors etanercept and infliximab.

METHODS

Patients with rheumatoid arthritis undergoing elective foot and ankle surgery over a 12-month period were prospectively followed for the development of complications in the postoperative period. All patients continued their antirheumatic medication schedule unaltered in the perioperative period. Data collected included sex, age, all medications used to treat rheumatoid arthritis, smoking history, and number of orthopaedic foot and ankle procedures performed. Patients were then stratified into two groups based on the use of immunomodulation via TNF-alpha inhibition (group 1) versus patients who did not receive TNF-alpha inhibition therapy (group 2). Groups 1 and 2 were followed and compared for the development of infectious/healing complications.

RESULTS

Thirty-one patients were enrolled in the study. Group 1 (n = 16) and group 2 (n = 15) patients were comparable for sex distribution, number of orthopaedic procedures performed, and use of steroids, methotrexate, leflunamide, and nonsteroidal anti-inflammatory drugs. Group 1 contained six times the number of smokers in group 2. At mean follow-up of 10.6 months (group 1) and 9.7 months (group 2), healing or infectious complications were similar in both groups. However, when total complications (healing + infection) were analyzed, group 1 (TNF-alpha inhibition, "higher risk") patients demonstrated a lower complication rate (p =.033).

CONCLUSIONS

The data suggest that in patients with rheumatoid arthritis undergoing elective foot and ankle surgery, the use of TNF-alpha inhibition agents may be safely undertaken in the perioperative period without increasing the risk of healing or infectious complications.

Consideration of the risk and treatment of tuberculosis in patients who have rheumatoid arthritis and receive biologic treatments

Evidence supports the association of tuberculosis (TB) with tumor necrosis factor inhibitor therapy in patients who have rheumatoid arthritis. There seem to be differential risks of TB with the currently available inhibitors. Screening for latent TB infection with purified protein derivative is indicated for patients who are being considered for treatment; it seems to be effective in reducing the occurrence of TB in treated patients.

A pilot study of the safety and tolerability of etanercept in patients with alcoholic hepatitis

BACKGROUND

Alcoholic hepatitis is a cause of major morbidity and mortality, and effective therapeutic regimens to treat this condition are lacking. Both experimental and clinical evidence indicates that tumor necrosis factor alpha (TNF), and the downstream cytokine interleukin-6 (IL-6), correlate with disease severity and may contribute to the pathogenesis and clinical sequelae of alcoholic hepatitis, thereby implicating a possible role for inhibition of TNF in the treatment of alcoholic hepatitis.

OBJECTIVE

The aim of the current study was to assess the safety and tolerability of a p75-soluble TNF receptor:FC fusion protein (etanercept), an agent that binds and neutralizes soluble TNF in patients with alcoholic hepatitis in the form of an open-label pilot trial.

METHODS

Etanercept administration was targeted for 2 wk duration in 13 patients with moderate or severe alcoholic hepatitis as assessed by a discriminant function value greater than 15 and/or the presence of spontaneous hepatic encephalopathy.

CONCLUSIONS

On an intention-to-treat basis, the 30-day survival rate of patients receiving etanercept was 92% (12/13). Adverse events that were encountered included infection, hepatorenal decompensation, and GI bleeding, which required premature discontinuation of etanercept in 23% of patients (3/13). This is the first study to examine TNF inhibition with etanercept in patients with alcoholic hepatitis and the results of this study support the rationale for larger controlled studies to further assess safety and efficacy.

Secondary immune deficiencies associated with biological therapeutics

Biological therapeutics have been utilized in the past several years for the treatment of various autoimmune, cardiovascular, and neoplastic conditions. As these agents target both pathologic and physiologic components of inflammatory and immune systems, the scientific community has been challenged to identify potential secondary immune deficiencies associated with their use. This article will focus on biological agents used for the treatment of rheumatoid arthritis, including tumor necrosis factor-a inhibitors, cytotoxic T lymphocyte-associated antigen-4 (CTLA-4 Ig), rituximab, and interleukin-1 receptor agonist (IL-1Ra). Both clinical and in vitro studies have been done to explore the potential immunomodulatory and immunosuppressive effects of these agents.

Combining the new biologic agents with our current psoriasis armamentarium

Combination therapy, rotational therapy, and sequential therapy have been used for psoriasis in attempts to achieve greater efficacy and greater safety. The purpose of this manuscript is to review potential advantages and disadvantages of new biologic agents as we look forward to their use in combination regimens with other systemic, topical, and light therapies. Data on the efficacy and toxicity of existing systemic therapies and new biologic agents is reviewed with an emphasis on potential additive or synergistic benefits or toxicities. The mechanism of action of biologic agents differs from systemic agents currently in use, suggesting that there may be additive effects in treating psoriasis. The absence of hepatotoxicity and nephrotoxicity are important advantages when considering combination therapy with biologic agents. The advantages of the use of biologic therapies in combination or rotation with other systemic agents will have to be demonstrated in clinical trials. Mechanisms of action of the biologic therapies suggest that there is potential for additive benefit when used in combination regimens.

Laboratory changes on anti-tumor necrosis factor treatment in rheumatoid arthritis

Tumor necrosis factor-alpha, acting through its receptors expressed on all cells of the body, is a key mediator of inflammation and immunity. However, its overproduction may also lead to pathologic changes. The latter situation occurs often in chronic inflammatory diseases such as rheumatoid arthritis. The concept suggesting tumor necrosis factor-alpha as a potential target emerged from experiments showing its key role in inducing many cytokines and mediators of inflammation. Several clinical trials targeting this cytokine in rheumatoid arthritis patients with a novel group of anti-tumor necrosis factor agents demonstrated reduced synovial inflammation and inhibition of bone and cartilage degradation. In addition to the therapeutic value of anti-tumor necrosis factor, analysis of laboratory changes not only proved the concept but provided new data, continuously expanding our understanding of the role of tumor necrosis factor-alpha in the pathogenesis of many diseases. These laboratory measures may also help the earlier identification of rheumatoid arthritis patients who have a less satisfactory response to this therapy.

Etanercept: an updated review of its use in rheumatoid arthritis, psoriatic arthritis and juvenile rheumatoid arthritis

Etanercept is a subcutaneously administered biological response modifier that binds and inactivates tumour necrosis factor-alpha, a proinflammatory cytokine. In patients with early active rheumatoid arthritis, etanercept 25mg twice weekly was associated with a more rapid improvement in disease activity and a significantly greater cumulative response than methotrexate over 12 months of treatment in a randomised, double-blind trial. In addition, etanercept recipients showed a slower rate of radiographic progression and a more rapid improvement in quality of life than methotrexate recipients. The efficacy of etanercept was maintained at 3 years' follow-up. Etanercept was also significantly better than placebo at reducing disease activity in patients who had an inadequate response to previous treatment with disease-modifying antirheumatic drugs (DMARDs) in several well controlled trials. At study end (after 3 or 6 months' treatment), the percentage of patients achieving an American College of Rheumatology 20% (ACR20) response with etanercept (25mg or 16 mg/m(2) twice weekly) was 59 to 75% as monotherapy and 71% in combination with methotrexate; corresponding placebo response rates were 11 to 14% and 27%, respectively. Response has been maintained in patients who continued treatment for up to 5 years. In patients with psoriatic arthritis, etanercept 25mg twice weekly significantly reduced disease activity and improved skin lesions in two double-blind, placebo-controlled, 12- to 24-week trials. In the 24-week study, ACR20 response rates (50 vs 13%), psoriatic arthritis response rates (70 vs 23%) and the median improvement in skin lesions (33 vs 0%) were significantly greater in etanercept than in placebo recipients. In patients with polyarticular-course juvenile rheumatoid arthritis, etanercept resulted in improvements in all measures of disease activity and was significantly more effective than placebo at reducing disease flare. Eighty percent of patients receiving etanercept achieved a >or=30% reduction in disease activity over 7 months of treatment, and this was maintained for up to 2 years in a trial extension. Etanercept was generally well tolerated in children and adults in clinical trials; the most commonly occurring adverse effects included injection site reactions, infection, headache, rhinitis and dizziness. In conclusion, etanercept has emerged as an important new treatment option in inflammatory arthritis. Etanercept provides rapid and sustained improvements in disease activity in patients with early and DMARD-refractory rheumatoid arthritis and has been shown to inhibit radiographic progression in those with early disease. Well controlled studies have also demonstrated the efficacy of etanercept in patients with psoriatic arthritis or polyarticular-course juvenile rheumatoid arthritis.