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

Successful Treatment Using Etanercept in a Patient with Enthesitis-Related Arthritis Who Had Late Allergic Reaction to Adalimumab

Background: Biological agents are considered important therapies and are increasingly used in the treatment of a range of rheumatological and inflammatory diseases. Nevertheless, the prevalent use of these treatments has been associated with increased incidence of drug-induced hypersensitivity reactions (HSR). Case Presentation: A 15-year-old patient with enthesitis-related arthritis developed late HSR after the use of adalimumab. Consequently, etanercept was used as an alternative treatment. Etanercept was administered subcutaneously through a single dose without any reaction upon examination using skin tests (skin prick test, intradermal test, and patch test) against likely cross-reactions given that both adalimumab and etanercept were anti-tumor necrosis factor (TNF) agents. Conclusions: Currently, TNF-α inhibitors find widespread use. Caution is required against HSR reactions, including systemic or local injection site reactions, although they are generally considered safe to use.

Etanercept-synthesizing adipose-derived stem cell secretome: A promising therapeutic option for inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic inflammatory condition of the gastrointestinal tract, with tumor necrosis factor (TNF)-α playing a key role in its pathogenesis. Etanercept, a decoy receptor for TNF, is used to treat inflammatory conditions. The secretome derived from adipose-derived stem cells (ASCs) has anti-inflammatory effects, making it a promising therapeutic option for IBD.

AIM

To investigate the anti-inflammatory effects of the secretome obtained from ASCs synthesizing etanercept on colon cells and in a dextran sulfate sodium (DSS)-induced IBD mouse model.

METHODS

ASCs were transfected with etanercept-encoding mini-circle plasmids to create etanercept-producing cells. The secretory material from these cells was then tested for anti-inflammatory effects both in vitro and in a DSS-induced IBD mouse model.

RESULTS

This study revealed promising results indicating that the group treated with the secretome derived from etanercept-synthesizing ASCs [Etanercept-Secretome (Et-Sec) group] had significantly lower expression levels of inflammatory mediators, such as interleukin-6, Monocyte Chemoattractant Protein-1, and TNF-α, when compared to the control secretome (Ct-Sec). Moreover, the Et-Sec group exhibited a marked therapeutic effect in terms of preserving the architecture of intestinal tissue compared to the Ct-Sec.

CONCLUSION

These results suggest that the secretome derived from ASCs that synthesize etanercept has potential as a therapeutic agent for the treatment of IBD, potentially enhancing treatment efficacy by merging the anti-inflammatory qualities of the ASC secretome with etanercept's targeted approach to better address the multifaceted pathophysiology of IBD.

Tackling TNF-α in autoinflammatory disorders and autoimmune diseases: From conventional to cutting edge in biologics and RNA- based nanomedicines

Autoinflammatory disorders and autoimmune diseases result from abnormal deviations of innate and adaptive immunity that heterogeneously affect organs and clinical phenotypes. Despite having etiologic and phenotypic differences, these two conditions share the onset of an aberrant inflammatory process. Targeting the main drivers controlling inflammation is useful to treat both autoimmune and autoinflammatory syndromes. TNF-α is a major player in the inflammatory immune response, and anti-TNF-α antibodies have been a revolutionary treatment in many autoimmune disorders. However, production difficulties and high development costs hinder their implementation, and accessibility to their use is still limited. Innovative strategies aimed at overcoming the limitations associated with anti-TNF-α antibodies are being explored, including RNA-based therapies. Here we summarize the central role of TNF-α in immune disorders and how anti-TNF-based immunotherapies changed the therapeutic landscape, albeit with important limitations related to side effects, tolerance, and resistance to therapies. We then outline how nanotechnology has provided the final momentum for the use of nucleic acids in the treatment of autoimmune and autoinflammatory diseases, with a focus on inflammatory bowel diseases (IBDs). The example of IBDs allows the evaluation and discussion of the nucleic acids-based treatments that have been developed, to identify the role that innovative approaches possess in view of the treatment of autoinflammatory disorders and autoimmune diseases.

The role of cytokines in migraine: A systematic review

BACKGROUND

Cytokines are important endogenous substances that are involved in immune and inflammatory responses. Neurogenic inflammation has been proposed to play a role in migraine involving altered cytokine levels. Therefore, we aimed to provide a systematic review on the current knowledge on cytokine levels in migraine patients during and outside attacks.

METHODS

Databases of PubMed and Embase were systematically searched for studies investigating cytokine levels in migraine patients during and outside attacks.

RESULTS

Screening yielded identification of 45 articles investigating 18 cytokines in total. We found that the interictal level of the anti-inflammatory cytokine, interleukin 10, was decreased, while the level of transforming growth factor beta 1 was increased in migraine patients compared to controls. Levels of pro-inflammatory cytokines, tumor necrosis factor α and interleukin 6, were increased outside attacks compared to controls. Ictal levels of cytokines were unchanged or varying compared to the interictal state in migraine patients. Three studies reported dynamic cytokines levels during the course of an attack.

CONCLUSION

The findings of the current review underline a possible involvement of cytokines in the proposed inflammatory mechanisms of migraine. However, future studies are needed to expand our knowledge of the exact role of cytokines in the migraine pathophysiology with focus on cytokines TNF-α, IL-1ß, IL-6 and IL-10 while applying refined methodology.

DRUGPATH: The Drug Gene Pathway Meta-Database

The complexity of modern-day diseases often requires drug treatment therapies consisting of multiple pharmaceutical interventions, which can lead to adverse drug reactions for patients. A priori prediction of these reactions would not only improve the quality of life for patients but also save both time and money in regards to pharmaceutical research. Consequently, the drug-gene-pathway (DRUGPATH) meta-database was developed to map known interactions between drugs, genes, and pathways among other information in order to easily identify potential adverse drug events. DRUGPATH utilizes expert-curated sources such as PharmGKB, DrugBank, and the FDA's NDC database to identify known as well as previously unknown/overlooked relationships, and currently contains 12,940 unique drugs, 3933 unique pathways, 5185 unique targets, and 3662 unique genes. Moreover, there are 59,561 unique drug-gene interactions, 77,808 unique gene-pathway interactions, and over 1 million unique drug-pathway interactions.

Etanercept to Control Inflammation in the Treatment of Complicated Neurocysticercosis

Manifestations of neurocysticercosis (NCC) are primarily due to host inflammatory responses directed at drug-damaged or naturally degenerating metacestodes (cysts) of the tapeworm Taenia solium. Prolonged high-dose corticosteroids are frequently required to control this inflammation in complicated disease, often causing severe side effects. Studies evaluating alternatives to corticosteroids are lacking. Here, we describe the clinical course of NCC in 16 patients prescribed etanercept (ETN), a tumor necrosis factor-alpha inhibitor to control inflammation resulting from anthelmintic treatment. Twelve patients with extraparenchymal NCC were administered ETN with corticosteroids (11/12, 91.7%) and/or methotrexate (9/12, 75.0%). The median age of the subgroup with extraparenchymal NCC was 40 years (range 26–57 years) and 66.7% were male. They were administered ETN for a median period of 311 days (range 31–461 days) and then followed for a median of 3.4 years (range 0.3–6.6 years). Among nine assessable patients, all improved clinically after starting ETN and one deteriorated transiently. Of the remaining three, one was lost to follow-up and two patients have improved but had not completed their assigned course. Four additional persons with recurrent perilesional edema (PE) episodes were given ETN for a median of 400.5 days (range 366–854 days) and followed post-ETN for a median of 1.7 years (range 0.2–2.4 years). All PE patients improved and two successfully tapered corticosteroids. Etanercept administration was associated with clinical improvement, stable disease, absence of recurrence, and lack of serious side effects. Etanercept appears to contribute to the control of inflammation and facilitate corticosteroid taper.

Subcutaneous Injectable Drugs Hypersensitivity and Desensitization: Insulin and Monoclonal Antibodies

Injectable drugs, including monoclonal antibodies, are becoming crucial components in the management of chronic diseases. The most common side effects are local reactions at the site of administration. With the increased and prolonged use of these medications, we are seeing increased reports of hypersensitivity reactions. The aim of this article is to discuss the signs and symptoms of these reactions as well as management, which may involve desensitization for 3 commonly encountered injectable drugs: tumor necrosis factor-α inhibitors (etanercept and adalimumab), insulin, and omalizumab.

Compliance with risk management plan recommendations on laboratory monitoring of antitumor necrosis factor-α therapy in clinical practice

BACKGROUND/PURPOSE

A risk management plan (RMP) was introduced to monitor the association between initiation of antitumor necrosis factor-α (anti-TNF-α) therapy and tuberculosis (TB) and viral hepatitis infections. The aim of this study was to assess adherence and predictors of laboratory-testing rates among patients treated with anti-TNF-α therapy.

METHODS

Data on patients receiving anti-TNF-α therapy between January 1, 2005, and November 31, 2013, were retrieved from a large medical organization in Taiwan. Newly-treated patients were categorized into pre- and post-RMP groups. Laboratory testing for TB and hepatitis B and C was ascertained and the proportion of new users receiving the test was compared between the pre- and post-RMP groups. Patient characteristics and concomitant medications used were investigated using multivariate logistic regression to determine the impact of each factor on laboratory testing.

RESULTS

Among 1128 new users, the initial testing rate of chest X-ray (CXR) for latent TB infection increased from 60.26% before RMP to 76.38% after RMP implementation; hepatitis B surface antigen (HBsAg) increased from 31.13% to 51.42%; and hepatitis C virus antibody (HCVAb) increased from 32.2% to 54.10%. CXR was significantly associated with age >60 years, higher Quan-Charlson comorbidity index score, psoriasis, and use of prednisolone (≥7.5 mg/d). Patients aged 40-60 years and with prednisolone doses of ≥7.5 mg/d and history of cancer were more likely to receive HBsAg or HCVAb tests than their counterparts.

CONCLUSION

The rate of laboratory test monitoring for anti-TNF-α therapy increased after RMP implementation. A strategy that integrates efforts from patient's education, health profession, and regulatory agencies is needed to improve safety screening and access to laboratory resources for the at-risk group of patients.

Biodistribution of etanercept to tissues and sites of inflammation in arthritic rats

Many monoclonal antibodies (mAbs) and other protein drugs have targets usually residing within tissues, making tissue concentrations of mAbs relevant to their pharmacologic effects. Therefore, knowledge of tissue distribution kinetics is important to better understand their pharmacokinetics and pharmacodynamics. The tissue distribution of mAbs is affected by many physiologic factors that may be altered in disease status. In the present work, we studied the tissue distribution kinetics of the fusion protein etanercept in inflamed joint tissues and examined the impact of inflammation on the tissue distribution of etanercept. Etanercept concentration profiles in plasma, blister fluid, and different tissues were obtained from healthy and collagen-induced arthritic (CIA) rats by use of a fluorescence quantification method via IRDye800CW labeling. Stepwise minimal and full physiologically based pharmacokinetic (PBPK) approaches were applied to characterize the distribution kinetics of etanercept in tissues in healthy and diseased animals. Etanercept exhibited modest tissue access (tissue/plasma area under the concentration curve [AUC] ratios 0.03-0.15 and estimated tissue reflection coefficients [σ] of 0.6-1.0), but with good penetration into arthritic paws (tissue/plasma AUC ratio 0.23 and σ 0.36). Etanercept exposure in the inflamed paws of CIA rats was approximately 3-fold higher than in normal paws taken from either CIA or healthy rats (tissue/plasma AUC ratios 0.23 versus 0.07 and σ 0.36 versus 0.71). The tissue distribution kinetics of etanercept in arthritic paws were well characterized with PBPK modeling approaches. Etanercept shows good penetration to arthritic paws in CIA rats. Our study indicates that inflammation produced increased tissue distribution of etanercept in CIA rats.

Etanercept: a review of its use in autoimmune inflammatory diseases

With its approval more than 15 years ago, subcutaneous etanercept (Enbrel(®)) was the first biological disease-modifying antirheumatic drug (bDMARD) and the first tumour necrosis factor inhibitor to be approved for use in rheumatic diseases. Etanercept remains an important cost-effective treatment option in adult patients with rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis or plaque psoriasis, and in paediatric patients with juvenile idiopathic arthritis or plaque psoriasis. In all of these populations, etanercept (with or without methotrexate) effectively reduced signs and symptoms, disease activity and disability, and improved health-related quality of life, with these benefits sustained during long-term treatment. The safety profile of etanercept during short- and long-term treatment was consistent with the approved product labelling, with adverse events being of a predictable and manageable nature. The introduction of etanercept and other bDMARDs as therapeutic options for patients with autoimmune rheumatic diseases and spondyloarthropathies revolutionized disease management and these agents continue to have a central role in treatment strategies. This article reviews the extensive clinical experience with etanercept in these patient populations.

Etanercept in the treatment of ankylosing spondylitis: A systematic review and meta-analysis

Etanercept (ETN) has been widely applied in the treatment of ankylosing spondylitis (AS). As the use of ETN has increased, associated adverse effects have been reported frequently. Previous meta-analyses have focused on comparing the differences in clinical outcomes between ETN and placebo (PBO). The present meta-analysis evaluated randomised controlled trials (RCTs) to compare the effects of ETN and a PBO or sulfasalazine (SSZ) in patients with AS. The study population characteristics and the main results, including the Assessment in AS 20% response (ASAS 20), the Bath AS Disease Activity Index (BASDAI) and the Bath AS Functional Index (BASFI), were extracted. The pooled odds ratios (ORs) or weighted mean differences (MDs) were calculated using a fixed or random effects model. Fifteen randomised controlled trials (RCTs) involving 2,194 subjects were included. Compared with a PBO, ETN significantly improved the ASAS 20 [P<0.00001; OR, 8.25; 95% confidence interval (CI), 5.92–11.50], BASDAI (P<0.00001; MD, −18.81; 95% CI, −24.47 to −13.15) and BASFI (P<0.00001; standard MD, −0.68; 95% CI, −0.85 to −0.50). In comparison with SSZ, ETN significantly decreased the BASDAI (P<0.00001; MD, −2.40; 95% CI, −2.89 to −1.90) and C-reactive protein (CRP) levels (P<0.0001; MD, −8.01; 95% CI, −11.73 to −4.29). The most common adverse effect of ETN was an injection site reaction. This meta-analysis shows that ETN monotherapy is effective in improving physical function and reducing disease activity in patients with AS. Compared with SSZ, ETN markedly decreased the BASDAI and CRP levels. However, the efficacy of ETN in treating AS requires further evaluation by more RCTs in a larger population of patients prior to recommending ETN as a substitute for synthetic disease-modifying antirheumatic drug (DMARD) monotherapy, or combinations of synthetic DMARDs.

Inhibition of tumor necrosis factor alpha reduces the outgrowth of hepatic micrometastasis of colorectal tumors in a mouse model of liver ischemia-reperfusion injury

Background

Patients with colorectal cancer (CRC) often develop liver metastases, in which case surgery is considered the only potentially curative treatment option. However, liver surgery is associated with a risk of ischemia-reperfusion (IR) injury, which is thought to promote the growth of colorectal liver metastases. The influence of IR-induced tumor necrosis factor alpha (TNF-α) elevation in the process still is unknown. To investigate the role of TNF-α in the growth of pre-existing micrometastases in the liver following IR, we used a mouse model of colorectal liver metastases. In this model, mice received IR treatment seven days after intrasplenic injections of colorectal CT26 cells. Prior to IR treatment, either TNF-α blocker Enbrel or low-dose TNF-α, which could inhibit IR-induced TNF-α elevation, was administered by intraperitoneal injection.

Results

Hepatic IR treatment significantly promoted CT26 tumor growth in the liver, but either Enbrel or low-dose TNF-α pretreatment reversed this trend. Further studies showed that the CT26 + IR group prominently increased the levels of ALT and AST, liver necrosis, inflammatory infiltration and the expressions of hepatic IL-6, MMP9 and E-selectin compared to those of CT26 group. Inhibition of TNF-α elevation remarkably attenuated the increases of these liver inflammatory damage indicators and tumor-promoting factors.

Conclusion

These findings suggested that inhibition of TNF-α elevation delayed the IR-enhanced outgrowth of colorectal liver metastases by reducing IR-induced inflammatory damage and the formation of tumor-promoting microenvironments. Both Enbrel and low-dose TNF-α represented the potential therapeutic approaches for the protection of colorectal liver metastatic patients against IR injury-induced growth of liver micrometastases foci.

Absence of a Pharmacokinetic Interaction between Etanercept and Warfarin

Etanercept, a soluble recombinant human tumor necrosis factor receptor (TNFr) fusion protein, is effective and well tolerated in the treatment of rheumatoid arthritis (RA), juvenile rheumatoid arthritis (JRA), psoriatic arthritis (PsA), and ankylosing spondylitis (AS). The primary objective of this study was to investigate the potential pharmacokinetic and pharmacodynamic interaction between a single dose of R- and S-enantiomers of warfarin and multiple doses of etanercept after administration of warfarin and etanercept alone and together. In a nonrandomized, three-period study, 12 healthy male subjects received a single oral 25-mg dose of warfarin after an overnight fast, followed by twice-weekly 25-mg subcutaneous doses of etanercept for seven doses. The last dose of etanercept was administered concurrently with a second dose of warfarin. Serial blood samples for plasma warfarin concentration measurement and international normalized ratio (INR) assessment were collected before and up to 144 hours after dose administration. Serial blood samples for serum etanercept concentration measurement were collected before and up to 60 hours after the sixth dose and 264 hours after the seventh dose. Etanercept did not affect the pharmacokinetics and pharmacodynamics of warfarin. All ratios of maximum serum concentration (C(max)) and area under the serum concentration versus time curve (AUC) for pharmacokinetics (R- and S-enantiomers of warfarin) and INR fell within the confidence interval of 0.8 to 1.25. Warfarin also did not cause a clinically significant alteration in the pharmacokinetics of etanercept. In conclusion, coadministration of etanercept and warfarin would not be expected to change the pharmacokinetics of either medication; therefore, no dosage adjustment is needed in cases in which warfarin and etanercept are coadministered.

Unaltered Etanercept Pharmacokinetics With Concurrent Methotrexate in Patients With Rheumatoid Arthritis

The purpose of this study was to evaluate the potential impact of concurrent weekly oral methotrexate administration on the pharmacokinetics of etanercept in patients with rheumatoid arthritis (RA) in a phase 3B trial. As part of a double-blind randomized trial of 682 patients with rheumatoid arthritis who received etanercept (25 mg subcutaneously twice weekly), methotrexate (weekly oral dose, median weekly dose: 20 mg), or etanercept (25 mg subcutaneously twice weekly) plus methotrexate (weekly oral dose, median weekly dose: 20 mg), serum etanercept concentrations were measured in a subset of patients. Serum samples for 98 randomly selected patients (48 receiving etanercept-alone treatment, 50 receiving etanercept plus methotrexate combination treatment) were analyzed to assess the pharmacokinetics of etanercept. A single blood sample was drawn from each patient at baseline and at the week 24 visit. Given the variable sampling time for patients in both groups, a population pharmacokinetic analysis using NONMEM was conducted for etanercept. A final covariate population pharmacokinetic model was constructed based on previously obtained etanercept data from both healthy subjects (n = 53) and patients with RA (n = 212) in 10 prior clinical trials. The predictive performance of the final model was assessed by both bootstrap and data-splitting validation approaches. The final model was then used to estimate Bayesian pharmacokinetic parameters for the patients in both treatments in the current trial. The potential effect of the concurrent administration of methotrexate on the pharmacokinetics of etanercept was examined by comparing the clearance values between 2 treatments using statistical criteria. A population 2-compartment model with first-order elimination from the central compartment and with either zero-order (intravenous administration) or first-order (subcutaneous administration) input was selected based on the data from the prior 10 etanercept clinical studies. The following pharmacokinetic parameters (typical value +/- standard error) were estimated: clearance (CL: 0.072 +/- 0.005 L/h), volume of distribution in the central compartment (V(c): 5.97 +/- 0.45 L), volume of distribution in the peripheral compartment (V(p): 2.05 +/- 0.32 L), intercompartment clearance (Q: 0.0645 +/- 0.0093 L/h), first-order absorption rate constant (k(a): 0.0282 +/- 0.0039 1/h), and absolute bioavailability for subcutaneous administration (F: 0.626 +/- 0.056). Interindividual variability of the pharmacokinetic parameters was quantified for CL (25.1%), V(c) (41.7%), k(a) (53.1%), and F (24.2%). Residual variability consisted of combined additive (11.4 ng/mL) and proportional error (49.9%). Both age (< 17 years) and body weight (< 60 kg) were found to be important covariates on CL. The results of both validation tests indicated the adequate predictive performance of the population model. Based on the bioequivalence criteria, the Bayesian-estimated clearance for patients receiving etanercept alone (mean: 0.070 L/h) was comparable to that for patients receiving a combination of etanercept and methotrexate (mean = 0.066 L/h). The pharmacokinetics of etanercept were not altered by the concurrent administration of methotrexate in patients with rheumatoid arthritis. Thus, no etanercept dose adjustment is needed for patients taking concurrent methotrexate.

Incidence and nature of infectious disease in patients treated with anti-TNF agents

Tumor necrosis factor alpha (TNF-alpha) inhibitors offer a targeted therapeutic strategy that contrasts with the nonspecific immunosuppressive agents traditionally used to treat most inflammatory diseases. These biologic agents have had a significant impact in ameliorating the signs and symptoms of inflammatory rheumatoid disease and improving patient function. From the onset of clinical trials, a central concern of cytokine blockade has been a potential increase in susceptibility to infections. Not surprisingly, a variety of infections have been reported in association with the use of TNF-alpha inhibitor agents. In particular, there is evidence suggesting an increased rate of granulomatous infections in patients treated with monoclonal TNF-alpha inhibitors. This review provides the incidence and nature of infections in patients treated with TNF-alpha inhibitor agents and reminds the clinician of the required vigilance in monitoring patients.

Poor reporting of search strategy and conflict of interest in over 250 narrative and systematic reviews of two biologic agents in arthritis: a systematic review

OBJECTIVE

To evaluate the quality of reviews about etanercept (ETN) and infliximab (IFX), two biologic treatments for rheumatoid arthritis (RA).

STUDY DESIGN

A comprehensive, systematic review, including searches of MEDLINE, EMBASE, and other electronic databases and hand-searches for published and unpublished literature. Two raters independently examined each article and identified systematic reviews as those including either a description of: (1) sources for identification and data retrieval; or (2) search strategy. They applied the quality of reporting of meta-analyses (QUOROM) instrument to systematic reviews.

RESULTS

Of 3,620 total citations, 281 were identified as reviews. Of these, 26 (9%) qualified as systematic rather than narrative. Overall, few reviews described selection of sources, critical appraisal, or quantitative summary or synthesis. Systematic reviews most often failed to explain validity assessment. Several articles did not disclose authors' participation in industry-funded clinical trials. Most reviews published in high impact factor and rheumatology journals did not meet many quality standards. Significant associations existed between review type (narrative vs. systematic) and reported funding (P=0.05), conflicts of interest (P=0.005), and country of publication (P<0.0001).

CONCLUSION

More than 90% of the published reviews were narrative and did not report methods and conflicts of interest in sufficient detail, raising concerns about selection and reporting bias.

Update on the use of etanercept across a spectrum of rheumatoid disorders

Etanercept is a soluble TNF receptor p75 fusion protein which is approved for subcutaneous use (50 mg weekly) in the treatment of patients with active rheumatoid arthritis (RA), juvenile RA, ankylosing spondylitis, and psoriatic arthritis. Etanercept binds to both TNFα and lymphotoxin and has quite a short mean half-life (70 hours). Numerous randomized clinical trials have demonstrated its efficacy to improve signs and symptoms in early and established RA and other inflammatory arthritis. Furthermore, etanercept has shown its ability to prevent radiographic progression and to improve health-related quality of life in patients with RA and psoriatic arthritis. A combination of etanercept plus methotrexate was more efficacious than etanercept monotherapy in RA patients but there is currently no evidence that such rheumatic combination is better than monotherapy in other disorders. Etanercept was generally well tolerated both in controlled trials with withdrawal rates being similar to the comparator groups and in large observational studies. Infections and injection-site reactions were the most frequently reported events. Serious infections were slightly increased but the occurrence of tuberculosis seemed less frequent than with anti-TNF monoclonal antibodies (infliximab and adalimumab). The benefit-risk ratio of etanercept appeared to be very positive, and this drug has now emerged as a major therapy in patients with active inflammatory arthritis. Furthermore, it is more frequently considered as an emerging and valuable option in patients with early disease.

Etanercept: a review of its use in the management of ankylosing spondylitis and psoriatic arthritis

Etanercept (Enbrel), a recombinant, dimeric, soluble tumour necrosis factor (TNF) receptor protein, is approved in various countries for the treatment of adult patients with ankylosing spondylitis or psoriatic arthritis. Monotherapy with subcutaneous etanercept 25mg twice weekly or 50mg once weekly was effective and generally well tolerated in patients with ankylosing spondylitis or psoriatic arthritis participating in several large, well designed clinical studies. Treatment with etanercept was more effective than placebo in reducing disease activity and improving health-related quality of life (HR-QOL) in both patient populations, and in delaying structural disease progression in patients with psoriatic arthritis. The beneficial response to etanercept achieved with shorter-term treatment was sustained in studies of up to 4 years' total duration. Randomised, well designed, head-to-head comparisons, including pharmacoeconomic analyses, with other anti-TNF biological modulators are required to accurately position etanercept and fully establish its cost effectiveness. In the meantime, etanercept is a valuable treatment option for patients with ankylosing spondylitis or psoriatic arthritis who are suitable candidates for therapy.

Pulmonary Sarcoidosis Associated with Etanercept Therapy

We present a case of probable pulmonary sarcoidosis associated with the use of etanercept for psoriatic arthritis. Other cases of etanercept-induced granulomas and skin sarcoidosis were recently published in the medical literature, but we found only one case that involved lung sarcoidosis during etanercept therapy. We describe a 40-year-old man who was receiving etanercept for severe psoriatic arthritis and was admitted to the hospital with dyspnea and subfebrile illness several months after the start of treatment. His diagnosis was consistent exclusively with sarcoidosis. The patient's symptoms improved when etanercept was discontinued, but they did not resolve completely. Treatment with prednisone 40 mg led to complete improvement of his pulmonary disease. Etanercept therapy can induce or exacerbate sarcoidosis. The disease disappears when etanercept is discontinued, although treatment with corticosteroids is sometimes required, as in our patient. Use of the Naranjo adverse drug reaction probability scale revealed a probable likelihood (score of 6) that the adverse reaction was related to etanercept. The association of etanercept with sarcoidosis is still a rare finding. This case highlights the importance of monitoring and possibly discontinuing the drug when sarcoidosis is suspected. Patients should be monitored during and after etanercept therapy for manifestations suggesting sarcoidosis, and we recommend patients receive baseline chest radiography at the start of therapy with follow-up of respiratory symptoms.

Efficacy and safety of etanercept in psoriasis/psoriatic arthritis: an updated review

The introduction in recent years of biologic medicines has greatly changed the treatment of psoriasis and psoriatic arthropathy (PsA). These drugs have been effective in the treatment of these chronic, physically weakening disorders, offering good efficacy and a safety profile that differs from those of all other systemic therapies and medications available to date. Different studies have assessed the efficacy and safety of etanercept in the treatment of psoriasis and PsA. Etanercept therapy for up to 144 weeks in psoriasis has shown maintenance of efficacy over time, recapture of initial clinical responses in patients who interrupted their etanercept therapy and were re-treated, an increased percentage of clinical responses in medium-dose non-responding patients who switched to higher dosages, good responses on quality-of-life tests, and an adverse event-adjusted rate similar to placebo. In PsA, etanercept therapy for up to 96 weeks was associated with inhibition of radiologic progression of the disease in addition to maintenance of efficacy over time and good responses on quality-of-life tests. In studies of patients with psoriasis, the adverse effects of etanercept were mostly mild, did not require discontinuation of treatment, and were not associated with cumulative toxicity over time. However, safety concerns about etanercept therapy are well known, and include injection-site reactions, infections, congestive heart failure, demyelinating diseases, lupus-like syndromes, and neoplasms. There are no data about any new safety concerns when etanercept is combined with systemic traditional therapies, although use of this therapy has been reported in only a small number of patients to date.Non-neutralizing anti-etanercept antibodies are not related to a decreased response to therapy and neutralizing antibodies have not been described to date. Treatment of patients infected with hepatitis C virus or HIV does not increase viral load in either case, affect liver function tests, or increase the risk of infections. To date, the available data suggest that use of etanercept during pregnancy or in breast-feeding women should be avoided. Children and the elderly may be treated with similar efficacy and safety profiles as have been observed in adults. Non-live vaccines can be administered to patients taking etanercept. Because of its long-term efficacy and safety, etanercept is likely to become a treatment option for consideration in the long-term management of patients with psoriasis and PsA.

Preliminary evaluation in rheumatoid arthritis activity in patients treated with TNF-alpha blocker plus methotrexate versus methotrexate or leflunomide alone

Methotrexate (MTX) is a first-line disease-modifying antirheumatic drugs (DMARD) in rheumatoid arthritis (RA). Leflunomide (LEF) and the biologic agents entered the arsenal of DMARDs in 1998. Therapeutic properties of new drugs are still under survey. The purpose of this study was to evaluate and compare the efficacy of MTX, LEF and a biologic agent (TNF-alpha blocker) combined with MTX in reducing disease activity in RA. Seventy-eight patients with active RA underwent a 24-week treatment with MTX 15 mg/week (30 pts), LEF 20 mg/day (30 pts) or a TNF-alpha blocker (etanercept 25 mg 2x weekly or infliximab 3 mg/kg in the week 0, 2, 6 and every 8 weeks thereafter) plus MTX 15 mg/week (18 pts). Only patients with RA resistant to MTX were included in groups receiving LEF or a biologic agent. During follow-up, patients' characteristics, disease characteristics, and clinical and laboratory data were registered. RA activity was evaluated using the ESR, tender and swollen joint counts, the duration of morning stiffness, disease activity score-28 (DAS 28), visual analogue scale (VAS) and health assessment questionnaire (HAQ). Treatment efficacy was demonstrated with ACR 20, 50 and 70 criteria. All groups revealed statistically significant improvement in all disease activity parameters measured. The percentage improvements were similar in groups treated with MTX and LEF and--except for VAS--significantly greater in the group treated with a biologic agent. Disease activity assessed by DAS 28 decreased significantly in all groups: the results were comparable in groups treated with MTX and LEF and significantly more prominent in the group treated with a TNF-alpha blocker. The ACR 20, 50 and 70 improvements amounted, respectively: 100, 50 and 7% in MTX group 87, 60 and 13% in LEF group and 100, 83 and 50% in a biologic agent group. The study revealed equal effectiveness of MTX and LEF in reducing disease activity in rheumatoid arthritis. The efficacy of a TNF-alpha blocker combined with MTX was higher than that of each conventional DMARDs, especially with regard to ACR 70 criteria (considerable improvement after treatment). LEF was equally effective as MTX in patients unable to continue MTX treatment due to the drug's ineffectiveness.

Tumor Necrosis Factor Antagonists: Different Kinetics and/or Mechanisms of Action May Explain Differences in the Risk for Developing Granulomatous Infection

OBJECTIVE

Tumor necrosis factor (TNF) antagonists fall into 2 classes:etanercept (ETA) is a soluble TNF receptor, while infliximab (INF) and adalimumab (ADA) are monoclonal antibodies against TNF. All 3 drugs are effective in treating rheumatoid arthritis. However, these agents have been associated with an increased risk of granulomatous infections, such as tuberculosis and histoplasmosis. Several reports indicate that the incidence of granulomatous infections may potentially be higher in individuals treated with INF than ETA.

METHODS

We conducted a comprehensive literature search (1966 to 2004) to review the role of TNF in normal and disease states, and the mechanisms of action of the TNF inhibitors. Specifically, we searched for possible mechanisms for the apparent increase in granulomatous infections associated with TNF inhibitors and for reasons that there may be differences between them.

RESULTS

Infection may result from a number of differences between ETA and INF or ADA. First, binding avidities are different, with ETA binding in a 1:1 ratio and INF/ADA binding in 2 to 3:1 ratios. Second, the clearances of ADA, ETA, and INF are different, being about 13 times higher for ETA than INF or ADA, thus resulting in higher steady-state drug levels for ADA and INF. Also, the methods of administration are different, intravenously (for INF) versus subcutaneously (for ETA and ADA), which results in lower peak concentrations for ETA and ADA, potentially explaining some of the differences in effects on granuloma formation. Third, INF and ADA have somewhat different mechanisms of action from ETA: INF and ADA are associated with antibody-mediated cell lysis, while ETA is not; INF may induce apoptosis in some tissues (eg, gastrointestinal [GI] mucosa) while ETA does not--although this is controversial and may not be true at steady state in synovium, where both drugs seem to cause apoptosis; ETA binds lymphotoxin-alpha while INF does not (ETA may thus be more efficient at preventing granuloma formation by this mechanism than INF); finally, ADA and INF seem to inhibit IFN-gamma expression (probably indirectly), while ETA does not.

CONCLUSIONS

There are significant differences between the 2 classes of TNF antagonists in terms of both their kinetics and mechanisms of action. These differences may help explain the apparent differences in the incidence of granuloma-dependent infections among them.

Contribution of TNFα, IL-1β and CINC-1 for articular incapacitation, edema and cell migration in a model of LPS-induced reactive arthritis

The protective effect of anti-CINC-1, -TNFalpha and -IL-1beta antisera on articular inflammatory incapacitation, articular diameter and synovial fluid cell content, which are correlated to nociception, edema and cell migration, respectively, were evaluated in a rat model of LPS-induced reactive arthritis. In this model, Escherichia coli lipopolysaccharide (LPS; 30 ng) was injected in a knee-joint previously primed with carrageenan (300 microg). Articular incapacitation was evaluated hourly by the automated registering of the knee-joint function during animal walking, and the knee-joint edema was evaluated by measuring the articular diameter increase. After 6 h, the animals were euthanized for collecting synovial fluid for the evaluation of cell migration. LPS produced dose-dependent incapacitation and edema. Anti-TNFalpha, -IL-1beta, and -CINC-1 antisera (20 and 40 microl) were used as pretreatment into knee-joint before LPS injection. At higher dose, Anti-TNFalpha and anti-CINC-1 were able to inhibit incapacitation, articular edema and mononuclear (MON) migration. Anti-IL1beta did not affect incapacitation at any dose, although inhibited edema and cell migration. Surprisingly, the higher dose of anti-IL1beta antisera did not inhibit cell migration, although inhibited articular edema. These findings corroborate the role TNFalpha has in different forms of arthritis, but points out the idea that CINC-1 (the homologue for human IL-8) may constitute a promising target for reactive arthritis management. Indeed, the potent antiedematogenic effect, and principally the anti-migration effect of anti-CINC-1, raises the possibility of a better control of disease progression than with anti-IL-1beta therapies.

The comparability of etanercept pharmacokinetics in healthy Japanese and American subjects

Thirty Japanese (J) and 32 American (A) healthy subjects received single doses of etanercept by subcutaneous injection, in 3 separate trials. Serum samples were collected for 480 hours after dosing. Concentrations were determined using enzyme-linked immunosorbent assay methods. Pharmacokinetic parameters were calculated using both non-compartmental and compartmental methods. Etanercept was slowly absorbed, with mean+/-SD time to maximum serum concentration of 47+/-15 hours (J), and 51+/-20 hours (A). The maximum serum concentration and area under the concentration time curve increased for doses 10 mg, 25 mg, and 50 mg, in a linear relationship. Etanercept was slowly eliminated, with observed mean+/-SD half-life of 80+/-25 hours (J) and 75+/-15 hours (A) and mean+/-SD apparent clearance of 144+/-65 mL/h (J) and 132+/-74 mL/h (A). Very low concentrations of etanercept were observed in the urine samples collected in the Japanese subjects. All adverse reactions observed resolved without issue, and none required discontinuation from the study.

Use of digital x ray radiogrammetry in the assessment of joint damage in rheumatoid arthritis

OBJECTIVE

To compare digital x ray radiogrammetry (DXR) with manual radiography for assessing bone loss in RA and examine the relationship of the scores obtained with other disease indices.

METHODS

225 consecutive consenting subjects attending the RA clinic were enrolled. An x ray examination was carried out; demographic details recorded; a self assessment questionnaire completed; blood taken for ESR measurement; and an assessment made by a trained nurse. All x ray films were scored manually using the modified Sharp technique by a single observer; 20 films were rescored by three readers. Films were assessed with the Pronosco X-Posure system, version 2.0. Analysis included chi2 tests, independent t tests, multiple linear regression, and partial correlations, as appropriate. The smallest detectable difference (SDD), coefficient of variation (CV), and coefficient of repeatability (CR) were determined from Bland and Altman plots.

RESULTS

The DXR precision varied: SDD = 0.002-0.9; CV = 0.09-5.9%; CR = 0.002-0.792, but was better than that of the intra- and interobserver Sharp scores: SDD = 73.9; CV = 27.8%; CR = 33.0-47.6. The DXR measurements, bone mineral density (R2 = 0.210), metacarpal index (R2 = 0.222), and cortical thickness (R2 = 0.215), significantly predicted Sharp scores. In women, DXR measurements significantly correlated with modified HAQ scores but with no other disease indices. Sharp scores significantly correlated with assessor's global assessment, swollen and tender joint counts, pain, HAQ, and DAS28.

CONCLUSION

DXR measurements are more precise than Sharp scores; both are related to long term disease activity in RA. DXR is simple to use, does not require intensive training, and may identify subjects not responding to standard treatment.

Etanercept monotherapy in patients with psoriasis: A summary of safety, based on an integrated multistudy database

BACKGROUND

Etanercept, a tumor necrosis factor antagonist, is an approved treatment in the United States and Europe for plaque psoriasis.

OBJECTIVE

To further examine the safety profile of etanercept in patients with chronic, moderate to severe plaque psoriasis.

METHODS

Safety data from an integrated database of 1347 patients from 3 randomized, double-blind, placebo-controlled clinical trials were analyzed. Safety end points included incidence rates of adverse events, serious adverse events, infections, serious infections, injection site reactions, and routine laboratory assessments. Pooled safety results from the first 12 weeks of each trial are reported here.

RESULTS

Rates of adverse events, serious adverse events, infections, and serious infections in the first 12 weeks of the 3 trials were similar among all active groups as well as each active group, compared with the placebo group. No dose-related toxicities were reported.

LIMITATIONS

This report includes a relatively short (12-week) time frame; data from patients exposed to etanercept for longer periods are needed.

CONCLUSIONS

Etanercept was generally safe in a large cohort of patients with moderate to severe plaque psoriasis.

Spotlight on etanercept in plaque psoriasis and psoriatic arthritis

Etanercept (Enbrel), a tumor necrosis factor (TNF)-alpha antagonist produced by recombinant technology, is approved for use in the US as subcutaneous monotherapy in adults with moderate-to-severe psoriasis who are candidates for systemic therapy or phototherapy. The drug is also indicated in patients with psoriatic arthritis, in whom it may be used in combination with methotrexate. In well designed trials in patients with moderate-to-severe psoriasis, short-term etanercept therapy (typically 25 or 50mg twice weekly) significantly increased the proportion of patients achieving a 75% reduction in the Psoriasis Area and Severity Index score compared with placebo. Similarly, in well designed trials in patients with psoriatic arthritis, treatment with short-term etanercept 25mg twice weekly, alone or in combination with methotrexate, improved clinical features of the disease, while radiographic progression of joint damage appeared to be significantly slowed in a nonblind 1-year extension. Short-term etanercept therapy was well tolerated in patients with psoriasis or psoriatic arthritis. Etanercept is thus a valuable new option for the treatment of patients with chronic moderate-to-severe plaque psoriasis (who are candidates for systemic therapy or phototherapy or have failed other systemic therapies) or with psoriatic arthritis.

Adalimumab

Adalimumab (Humira) is a recombinant, fully human anti-tumor necrosis factor (TNF) monoclonal antibody approved in the US and Europe for the treatment of adult patients with moderate to severe, active rheumatoid arthritis (RA). In combination with methotrexate or standard antirheumatic therapy or as monotherapy, adalimumab effectively reduced signs and symptoms of RA, induced remission, improved physical function and inhibited the progression of structural damage in several randomized, double-blind, placebo-controlled phase III trials. The drug was generally well tolerated, with most adverse events being mild to moderate, and the serious adverse events profile being similar to that generally seen in patients with RA not receiving anti-TNF agents. Adalimumab was at least as cost effective as other anti-TNF agents used in the therapy of RA, and provided significant improvements in patients' health-related quality of life. Overall, adalimumab in combination with methotrexate or standard antirheumatic therapy is valuable as a first-line therapeutic option in patients with early, aggressive RA, and a second-line therapeutic option in patients with long-standing, moderate to severe RA. For the latter indication, adalimumab may also be used as monotherapy.

Lethal acute respiratory distress syndrome during anti-TNF-alpha therapy for rheumatoid arthritis

Tumor necrosis factor alpha (TNF-alpha) blocking drugs improve therapy for rheumatic diseases, but the risk of additional immunosuppression and infection is unclear. We report on a patient with rheumatoid arthritis treated with etanercept for 2 years, in addition to methotrexate and prednyliden, who developed fulminant pneumococcal pneumonia with rapid progression to fatal acute respiratory distress syndrome (ARDS) and septic shock. In patients receiving anti-TNF-alpha therapy, especially in combination with corticosteroids, signs of pulmonary infection should be regarded as very serious, as fulminant pneumonia with ARDS and severe sepsis may develop within 24 h.

Tumour necrosis factor (TNFalpha) as a novel therapeutic target in symptomatic corticosteroid dependent asthma

BACKGROUND

Tumour necrosis factor alpha (TNFalpha) is a major therapeutic target in a range of chronic inflammatory disorders characterised by a Th1 type immune response in which TNFalpha is generated in excess. By contrast, asthma is regarded as a Th2 type disorder, especially when associated with atopy. However, as asthma becomes more severe and chronic, it adopts additional characteristics including corticosteroid refractoriness and involvement of neutrophils suggestive of an altered inflammatory profile towards a Th1 type response, incriminating cytokines such as TNFalpha.

METHODS

TNFalpha levels in bronchoalveolar lavage (BAL) fluid of 26 healthy controls, 42 subjects with mild asthma and 20 with severe asthma were measured by immunoassay, and TNFalpha gene expression was determined in endobronchial biopsy specimens from 14 patients with mild asthma and 14 with severe asthma. The cellular localisation of TNFalpha was assessed by immunohistochemistry. An open label uncontrolled clinical study was then undertaken in 17 subjects with severe asthma to evaluate the effect of 12 weeks of treatment with the soluble TNFalpha receptor-IgG1Fc fusion protein, etanercept.

RESULTS

TNFalpha levels in BAL fluid, TNFalpha gene expression and TNFalpha immunoreative cells were increased in subjects with severe corticosteroid dependent asthma. Etanercept treatment was associated with improvement in asthma symptoms, lung function, and bronchial hyperresponsiveness.

CONCLUSIONS

These findings may be of clinical significance in identifying TNFalpha as a new therapeutic target in subjects with severe asthma. The effects of anti-TNF treatment now require confirmation in placebo controlled studies.

Etanercept: a review of its use in the management of plaque psoriasis and psoriatic arthritis

Etanercept (Enbrel), a tumor necrosis factor-alpha antagonist produced by recombinant technology, is approved for use in the US as subcutaneous monotherapy in adults with moderate-to-severe psoriasis who are candidates for systemic therapy or phototherapy. The drug is also indicated in patients with psoriatic arthritis, in whom it may be used in combination with methotrexate. In well designed trials in patients with moderate-to-severe psoriasis, short-term etanercept therapy (typically 25 or 50 mg twice weekly) significantly increased the proportion of patients achieving a 75% reduction in the Psoriasis Area and Severity Index score compared with placebo. Similarly, in well designed trials in patients with psoriatic arthritis, treatment with short-term etanercept 25 mg twice weekly, alone or in combination with methotrexate, improved clinical features of the disease, while radiographic progression of joint damage appeared to be significantly slowed in a nonblind 1-year extension. Short-term etanercept therapy was well tolerated in patients with psoriasis or psoriatic arthritis. Etanercept is thus a valuable new option for the treatment of patients with chronic moderate-to-severe plaque psoriasis (who are candidates for systemic therapy or phototherapy or have failed other systemic therapies) or with psoriatic arthritis.

Is there a role for tumor necrosis factor-alpha inhibitors and especially thalidomide in dermatology?

Because of the relative shortcomings and their side effects of the available anti-inflammatory drugs such as systemic nonsteroids, corticosteroids, and immunosuppressive drugs, and since tumor necrosis factor-a plays a major role in noninfectious inflammatory and autoimmune disorders, tumor necrosis factor-a inhibitory drugs and the available tumor necrosis factor-a inhibitory biologic modifying reagents are described. Among the drugs reviewed are pentoxifylline, thalidomide, etanercept, infliximab, and adalimumab. Their relative effectiveness and side effects are reported and recommendations are made.

Etanercept: in ankylosing spondylitis

Etanercept is a dimeric fusion protein based on the p75 tumor necrosis factor (TNF) receptor. It binds to TNFalpha and blocks its biological activity. Subcutaneous etanercept is effective in the treatment of rheumatoid arthritis, psoriatic arthritis, and polyarticular-course juvenile rheumatoid arthritis. More recently, etanercept has shown efficacy in the treatment of adults with ankylosing spondylitis. In randomized, double-blind, placebo-controlled trials, subcutaneous etanercept 25mg twice weekly for 6-24 weeks significantly reduced disease activity in patients with active ankylosing spondylitis. In the largest trial, etanercept produced a response rate of 57% compared with 22% for placebo after 24 weeks (response was determined via the validated ASAS 20 response criteria developed by the Assessments in Ankylosing Spondylitis [ASAS] Working Group). Etanercept therapy significantly improved health-related quality of life in patients with ankylosing spondylitis compared with placebo. The greatest improvements in a 16-week study were seen in the domains of physical functioning, physical role, bodily pain, vitality, and social functioning. Etanercept was generally well tolerated, with few serious adverse events or treatment withdrawals. The most common adverse events were injection-site reactions and minor upper respiratory tract infections.

Immunotherapeutic approaches in multiple sclerosis

The progress in understanding the mechanisms of T cell activation, inactivation and modulation has been translated into different immunotherapeutic strategies aiming at treating multiple sclerosis (MS). Key attack points for selective immunointervention in MS include modulation of antigen recognition, costimulation blockade, induction of regulatory cells, deviation to non-pathogenic or protective responses, neutralization of proinflammatory cytokines and administration of anti-inflammatory cytokines. In addition, several attempts have been made using less specific forms of immunointervention. The two resounding successes in the immunotherapy of MS, IFN-failed and glatiramer acetate, contrast with the many attempts, equally based on sound reasoning and promising animal data. Nevertheless, antigen-based immunointervention will continue to be tested clinically, and we will certainly witness the application of more articulate strategies able to selectively target cytokine production by Th1 or Th2 cells or to modify the Th1/Th2 balance. Perhaps, an effective manipulation of pathogenic and protective cells in MS may eventually rely on a combination of antigen- and cytokine-based approaches to selectively target autoreactive T cells and divert them from autoaggression. Most importantly, new avenues are opening, such as the use of chemokine receptor antagonists, and others look very promising, as targeting dendritic cells to favour their capacity to induce regulatory T cells.

Etanercept: a pharmacoeconomic review of its use in rheumatoid arthritis

Etanercept (Enbrel), which inhibits the activity of tumour necrosis factor-alpha, is indicated in the treatment of patients with active rheumatoid arthritis (RA). A lifetime cost-utility analysis in patients with severe disease-modifying antirheumatic drug (DMARD)-resistant RA in the UK suggested that etanercept is associated with acceptable cost-utility ratios relative to traditional nonbiological DMARDs. In a 12-month cost-utility study in Spain, etanercept was predicted to be dominant over infliximab plus methotrexate in patients with active, refractory RA with regards to the cost per QALY gained and cost per American College of Rheumatology (ACR) 20 response achieved. In short-term cost-effectiveness analyses conducted in the US, the cost effectiveness of etanercept relative to other treatments in patients with methotrexate-naive or -resistant RA depends on whether predicted incremental cost-effectiveness ratios of at least USD 41,900 per ACR 20 response or USD 34,800 per ACR 70 weighted response over a 6-month period are considered acceptable (1999 values). The relative efficacy and cost effectiveness of etanercept and other biological DMARDs will be clarified when appropriate data from directly comparative clinical and/or long-term pharmacoeconomic studies become available. Etanercept may prevent or delay disability, which may produce reductions in nondrug costs that could help offset its acquisition cost.

Adalimumab

Adalimumab (Humira) is a recombinant, fully human IgG1 monoclonal antibody that binds specifically to tumor necrosis factor (TNF)-alpha, thereby neutralizing the activity of the cytokine. Subcutaneous adalimumab has been investigated in well designed trials in patients with active rheumatoid arthritis despite treatment with disease-modifying antirheumatic drugs (DMARDs). Patients receiving adalimumab 40mg every other week in combination with methotrexate (Anti-TNF Research Study Program of the Monoclonal Antibody Adalimumab [ARMADA] and DE019 trials) or standard antirheumatic therapy (Safety Trial of Adalimumab in Rheumatoid Arthritis [STAR] trial) for 24-52 weeks had significantly higher American College of Rheumatology (ACR) 20, ACR50, and ACR70 response rates than patients receiving placebo plus methotrexate or standard antirheumatic therapy. In ARMADA, an ACR20 response was achieved in 25%, 52%, and 67% of adalimumab plus methotrexate recipients at weeks 1, 4, and 24, respectively. In ARMADA and DE019, improvements in the individual components of the ACR response were significantly greater with adalimumab 40mg every other week plus methotrexate than with placebo plus methotrexate. Monotherapy with adalimumab 40mg every other week was associated with significantly higher ACR20, ACR50, and ACR70 response rates than placebo, as well as significantly greater improvements in the individual components of the ACR response. ACR responses were sustained with adalimumab according to the results of extension studies in which patients received adalimumab in combination with methotrexate (up to 30 months) or as monotherapy (up to 5 years). In both concomitant therapy and monotherapy trials, adalimumab was associated with significantly greater improvements from baseline in health-related quality of life (HR-QOL) measures than placebo; adalimumab also retarded the radiographic progression of structural joint damage to a significant extent compared with placebo. Adalimumab was generally well tolerated as both concomitant therapy and monotherapy. In ARMADA, there were no significant differences between adalimumab and placebo (in combination with methotrexate) in the incidence of adverse events; however, in STAR, the incidence of injection site reactions, rash, and back pain was significantly higher with adalimumab than with placebo (in combination with standard antirheumatic therapy). No cases of tuberculosis were reported in either trial.In conclusion, subcutaneous adalimumab in combination with methotrexate or standard antirheumatic therapy, or as monotherapy, is effective in the treatment of adults with active rheumatoid arthritis who have had an inadequate response to DMARDs. Adalimumab has a rapid onset of action and sustained efficacy. The drug also retards the progression of structural joint damage, improves HR-QOL, and is generally well tolerated. Thus, adalimumab is a valuable new option for the treatment of DMARD-refractory adult rheumatoid arthritis.