Search for: rheumatoid arthritis methotrexate autoimmune disease biomarker gene expression GWAS HLA genes non-HLA genes
| ID | PMID | Title | PublicationDate | abstract |
|---|---|---|---|---|
| 12510358 | [Methotrexate for the treatment of rheumatoid arthritis in Japan--much more still remains | 2002 Dec | Methotrexate(MTX) is an antifolic agent and has been widely used for RA since early 1980s. Since 1999 when MTX was approved as an antirheumatic drug in Japan, patients taking MTX has been increasing and about sixty thousands patients are estimated to be taking MTX for the treatment of RA. The highest efficacy relative to toxicity of MTX is supported by the highest retention rate among current DMARDs. Therefore, most of rheumatologist places MTX as a golden standard of DMARD. Recent RCT data in European and North American countries showed that ACR 20 and 50 responses are ranging from 60 to 70% and from 40 to 50%, respectively. In these clinical trials, MTX was usually started at a dose of 7.5 mg weekly and then increased to 15-20 mg/week if the disease activity was still present since the clinical effect of MTX is related to the dose in the range 5 to 20 mg weekly. However, an upper limit of clinical dose of MTX (Rheumatrex) for RA is set to 8 mg weekly and this is a major problem because the majority of patients with active RA need higher doses for the suppression of arthritis. This matter needs an immediate solution. If MTX would be used aggressively for the early suppression of RA, informed consent regarding MTX dose and side effects including their earlier signs should be obtained, especially when patients are taking more than 8 mg weekly. | |
| 12641492 | Spotlight on etanercept in rheumatoid arthritis, psoriatic arthritis and juvenile rheumato | 2003 | Etanercept (Enbrel) 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 59-75% as monotherapy and 71% in combination with methotrexate; corresponding placebo response rates were 11-14% 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. | |
| 12124857 | High levels of osteoprotegerin and soluble receptor activator of nuclear factor kappa B li | 2002 Jul | OBJECTIVE: To test the hypotheses that 1) proinflammatory cytokines affect osteoprotegerin (OPG) and soluble receptor activator of nuclear factor kappa B ligand (sRANKL) production and therefore the OPG and sRANKL levels differ in rheumatoid arthritis (RA) patients in comparison with healthy individuals; and 2) anti-tumor necrosis factor alpha (anti-TNF alpha) therapy influences OPG and sRANKL levels. METHODS: Sera were obtained from healthy individuals or RA patients receiving the combination of infliximab and methotrexate. Peripheral blood mononuclear cells (PBMCs) and synovial fluid mononuclear cells (SFMCs) were isolated from RA patients. Fibroblast-like synoviocytes (FLS) were isolated from synovial tissue obtained at total knee replacement in RA patients. Supernatants from cells stimulated with cytokines were collected after culture in vitro. Concentrations of OPG and sRANKL were determined by enzyme-linked immunosorbent assays. RESULTS: A strong positive correlation between OPG concentration and age was observed in healthy individuals but not in RA patients. The OPG and sRANKL levels were higher in RA patients than in healthy controls. Cultured FLS spontaneously secreted much higher amounts of OPG than PBMCs or SFMCs. Proinflammatory cytokines enhanced OPG production. Anti-TNF alpha treatment resulted in the normalization of serum OPG and sRANKL levels in RA patients without influencing the OPG:sRANKL ratio. CONCLUSION: Although higher serum levels of OPG and sRANKL are present in RA patients than in healthy individuals, the ratio of OPG:sRANKL is similar. There is an age-dependent increase of OPG but not sRANKL levels in healthy subjects. Anti-TNF alpha treatment results in the normalization of elevated levels of OPG and sRANKL in RA patients. | |
| 12510365 | [Infliximab in the treatment of rheumatoid arthritis]. | 2002 Dec | Infliximab is a chimeric monoclonal antibody capable of neutralizing human TNF alpha. A number of clinical trials for the treatment of rheumatoid arthritis(RA) with infliximab indicated that TNF alpha blockade was effective and well tolerated with the excellent results occurring at 3 and 10 mg/kg in combination with methotrexate. Treatment of RA patients with the combination of infliximab and methotrexate also prevented radiographic evidence of progression of joint damage. If the clinical efficacy is sustained and the safety is confirmed over the long term, infliximab may become an essential agent of choice for the treatment of RA. | |
| 15146441 | Skin reaction to adalimumab. | 2004 May | The tumor necrosis factor alpha (TNFalpha) inhibitors etanercept and infliximab have shown good clinical results in the treatment of rheumatoid arthritis and other autoimmune disorders. With these novel fusion proteins, immune-mediated side effects, among them various cutaneous reactions, have been encountered. We report herein the case of an erythema multiforme-like skin reaction to treatment with the monoclonal anti-TNFalpha antibody adalimumab in a patient with rheumatoid arthritis. The reaction occurred after the sixth injection and affected the palms and soles as well as the injection site. Discontinuation of the adalimumab therapy resulted in rapid improvement of the condition. Although this patient was receiving concomitant immunomodulatory therapy with methotrexate and leflunomide, these medications were not discontinued when the reaction developed, and no other potential pathogenetic mechanisms were identified. We believe the reaction is most likely attributable to adalimumab. | |
| 12510362 | [Efficacy of leflunomide]. | 2002 Dec | Leflunomide(Arava) is a novel immunomodulatory drug, the primary action of which is inhibition of de-novo pyrimidine synthesis by selective inhibition of dihydro-orotate dehydrogenase. It has been shown that leflunomide is effective in treating active rheumatoid arthritis(RA) in a placebo-controlled phase II study. Subsequent multinational, randomized, controlled phase III clinical trials demonstrated that leflunomide is as effective and safe as methotrexate and sulfasalazine in treatment of RA. Frequently reported adverse effects included diarrhea, nausea and vomiting, skin rash, reversible alopecia, and transient lever enzyme elevations. However, accumulating concerns about its toxic effects, especially hepatotoxicity, have been raised recently. In addition, rheumatologists should be aware that leflunomide has a much longer half life than any other disease modifying antirheumatic drug. | |
| 15767955 | [Respiratory complications of new treatments for rheumatoid arthritis]. | 2004 Dec | INTRODUCTION: Treatment of rheumatoid arthritis (RA) has changed with the release of more efficient disease-modifying anti-inflammatory drugs (DMARDs) and biologicals, such as methotrexate, leflunomide and TNF blockers, respectively. However they are prone to trigger potential pulmonary side effects. STATE OF KNOWLEDGES: Diffuse interstitial pneumonitis with alveolar lymphocytosis are induced by methotrexate. This drug increases also the risk of opportunistic infections (Pneumocyctis carinii) and of delayed lymphomas. Many intracellular bacterial infections, about 80 cases of diffuse pneumonitis, and rare vasculitis are attributable to leflunomide. PERSPECTIVES: The TNF blocking agents (infliximab, etanercept and adalimumab) trigger immunization and consequently, rare type I and III hypersensitivity pneumonitis, serological lupus-like reactions usually without any clinical manifestations. Indeed the risk of infection with intracellular agents remains the first concern. Several hundreds of cases of pulmonary and non pulmonary tuberculosis (TB) have been described. They present as disseminated forms, with pulmonary manifestations present in half cases; of note, other sites are atypical, namely meningitis, lymph node, and digestive involvement. Pathological diagnosis can be difficult since granulomas are sparse or absent. Therefore TB can be lethal because of delayed diagnosis and treatment. CONCLUSION: To prevent this major risk when using TNF blockers, the French agency AFFSAPS recommends to screen and treat susceptible patients such as latent tuberculosis. Specifically, antituberculous drugs have to be started three weeks before anti-TNF agents. During biological therapy, physicians must regularly look for usual and unusual symptoms of TB. When TB is diagnosed, anti -TNF agents have to be discontinued, probably definitively, and appropriate antituberculosis treatment started in order to achieve an uneventful course. | |
| 12138686 | [Infliximab combined with methotrexate in the treatment of rheumatoid arthritis]. | 2002 Jul | Infliximab is a chimeric anti-tumor necrosis factor alpha (anti-TNF-alpha) monoclonal IgG1 antibody successfully used for the treatment of active rheumatoid arthritis (RA) not completely controlled with methotrexate or other disease modifying anti-rheumatic drugs. We evaluated both clinical efficacy and safety of infliximab in 63 patients with persistently active RA (Disease activity score > or = 3.7). All the patients received infliximab (3 mg/Kg) at week 0, 2, 6 and then every 5 weeks in combination with methotrexate (7.5-10 mg/week) in an open label study. At week 14th, ACR 20% response criteria have been fulfilled by 43 (91.4%) out of 47 patients, 31 (72%) of them achieving also an ACR 50% and 9 (21%) an ACR 70% response. At the time of this report 33 patients touched 22 weeks of treatment: ACR 20% response was achieved in 95%, while ACR 50% and ACR 70% were respectively found in 78% and 39% of the cases. Only 1 case of bronchopulmonary mycosis and 2 of mild urticaria were observed. The initiation of infliximab therapy in patients with active RA resulted in a rapid and sustained improvement of articular manifestations and quality of life. Even though, major adverse events were rare, clinicians should be aware of this possibility. | |
| 12715722 | [Interleukin-1 receptor antagonists in the treatment rheumatoid arthritis]. | 2002 | Interleukin-1 (IL-1) is one of the main inflammatory mediators associated with development of rheumatoid arthritis (RA). Deficiency in secretion of the natural IL-1 antagonist was found in RA patients, and enhanced joint inflammation. This finding was confirmed by numerous studies using the animal model of the disease. Two randomized, multicenter clinical trials with anakinra, a recombinant IL-1 receptor antagonist (rHHHuIL-1Ra), revealed that application of anakinra with or without methotrexate induces remission (ACR 20) in 38-71% of patients with RA. Induction of remission was dose and treatment-time-dependent. The present paper reviews theoretical application of rHuIL-1Ra in patients with RA and summarizes results of published clinical trials of the drug. | |
| 15168143 | The prevalence of subclinical amyloidosis in Polish patients with rheumatoid arthritis. | 2004 Jun | The aims of this study were to determine the proportion of rheumatoid arthritis (RA) patients attending hospital in whom amyloid deposits were present in abdominal fat aspiration (AFA) samples, and to assess possible risk factors for amyloid development in RA. One -hundred and twenty-one patients (16 males, 105 females) with RA referred to the Department of Rheumatology in Wroclaw between 1996 and 2001 were studied regardless of RA duration or laboratory findings. Abdominal subcutaneous fine-needle aspiration was performed, and samples of adipose tissue stained with alkaline Congo red then examined by polarized light microscopy. The presence or absence of amyloid fat deposits (AFD) was determined according to whether typical apple-green birefringence was observed. Amyloid deposits were found in 35 (29%) patients. Amyloidosis was significantly more common in males and in patients with longer disease duration. Patients with AFD had previously undergone less treatment with disease-modifying antirheumatic drugs (DMARDs) than those without AFD, and significantly fewer patients with AFD had previously taken methotrexate than those without AFD (25% vs 45%; p<0.01). Renal involvement was found in 12 of 35 patients with AFD (34%). Using the AFA technique, amyloid deposits were found commonly in RA patients, particularly in males with longer disease duration and in patients not treated intensively with DMARDs, especially methotrexate. AFA has potential useful application as a method for detecting amyloidosis before the overt occurrence of renal or other pathology related to amyloid deposits. | |
| 12649401 | Influence of therapy with chimeric monoclonal tumour necrosis factor-alpha antibodies on i | 2003 Apr | INTRODUCTION: It has been shown that T lymphocytes and monocytes/macrophages, producing pro-inflammatory cytokines, play a pivotal role in the pathophysiology of rheumatoid arthritis (RA). In recent placebo-controlled double-blind randomized studies, chimeric (human/mouse) tumour necrosis factor-alpha (TNFalpha) antibodies (cA2) proved to be very effective in improving clinical disease activity and reducing inflammatory parameters in RA. OBJECTIVE: To investigate whether anti-TNFalpha therapy influences the in vitro intracellular cytokine production in peripheral blood monocytes and T lymphocytes of RA patients after one single (24 h) and multiple intravenous infusions (6 months). METHODS: An intracellular flow cytometric technique was applied to measure interleukin 1beta (IL-1beta), IL-6, TNFalpha, IL-10 and IL-12 in monocytes and IL-2, IL-4 and interferon-gamma in T lymphocytes of 15 patients, before, after 24 h and after 6 months of therapy with monoclonal chimeric anti-TNFalpha antibodies (3 mg/kg, bimonthly i.v.). All patients were on stable therapy with methotrexate (15-20 mg/week i.m.). Cytokine content in monocytes was measured directly after blood sampling (basal levels), after 8 h of culture (spontaneous production) and after 8 h of stimulation with lipopolysaccharides (LPS-stimulated production). RESULTS: Basal levels and production (after 8 h) of IL-1beta, IL-6 and TNFalpha were significantly decreased 24 h after the first administration of anti-TNFalpha (for IL-1beta P < 0.01; for IL-6 P < 0.01; for TNF P < 0.003) and after 6 months of therapy (for IL-1beta P < 0.02; for IL-6 P < 0.03; for TNFalpha P < 0.001). For IL-12, basal levels were significantly decreased 24 h and 6 months after the start of therapy with anti-TNFalpha antibodies (P=0.0001; P=0.003, respectively). In contrast, IL-10 production increased significantly after 24 h and after 6 months (P=0.02; P=0.01). The T(H2)/T(H1) cytokine ratio in CD4+ T cells was significantly increased after 24 h and after 6 months of anti-TNFalpha therapy (P=0.003; P=0.0007). CONCLUSION: Anti-TNFalpha therapy might down-regulate the monocytic capacity to produce pro-inflammatory cytokines and induces a shift to a more pronounced anti-inflammatory T(H2) cytokine production. | |
| 12111628 | Analysis of the reasons for DMARD therapy discontinuation in patients with rheumatoid arth | 2002 Jun | The aim of the study was to evaluate the efficacy and safety of disease-modifying drugs (DMARDs) in everyday clinical practice in Central European States (the Czech and Slovak republics). This was a retrospective, multicentre study. With the help of a special questionnaire, the medical files of 760 patients in 15 centres were analysed looking for reasons for DMARD discontinuation (e.g. insufficient efficacy, toxicity). The secondary endpoints were duration of therapy with individual DMARDs and the influence of other factors (demographic, disease specific, concomitant therapy) on duration of therapy. In 47.1 % of patients therapy was interrupted because of lack of efficacy, in 43.2 % because of adverse events, and in 9 % for undefined reasons. Toxic reactions leading to withdrawal were most common with gold (62.6 %) and methotrexate (62.5 %). Because of insufficient effect, treatment was most frequently interrupted with antimalarials (62.3 %) and penicillamine (53.2 %), but in only 22% treated with methotrexate. The mean duration of one treatment episode with DMARDs was 28.1 +/- 48.9 months. Surprisingly, it was longest for cyclophosphamide (53.5 + 55.1 months) and shortest for cyclosporin (7.0 +/- 6.7 months). The mean duration of treatment with methotrexate was only 14.9; +/- 16.2 months. The mean duration of treatment with one DMARD was statistically longer in patients with positive rheumatoid factor, extra-articular disease and age lower than 50 years. There was no impact of sex, concomitant steroid treatment and high or low sedimentation rate on treatment duration. Considerable differences in everyday clinical practice with DMARDs between Central European states and published data from the US and western Europe have been found. More education about modern strategies in the treatment of RA is probably necessary for practising rheumatologists. | |
| 12874640 | [Kidney involvement in rheumatoid arthritis]. | 2003 | Rheumatoid Arthritis (RA) is a widespread disease and its renal involvement, relatively common, is clinically significant because worsens course and mortality of the primary disease. There is still no agreement on the prevalence of renal disorders in RA: data analysis originates from different sources, as death certificates, autopsies, clinical and laboratory findings and kidney biopsies, each with its limitations. Histoimmunological studies on bioptical specimens of patients with RA and kidney damage, led to clarify prevalent pathologies. In order of frequency: glomerulonephritis and amyloidosis (60-65% and 20-30% respectively), followed by acute or chronic interstitial nephritis. Kidney injury during RA includes secondary renal amyloidosis, nephrotoxic effects of antirheumatic drugs and nephropathies as extra-articular manifestations (rheumatoid nephropathy). Amyloidosis affects survival, increases morbidity and is the main cause of end stage renal disease in patients with RA and nephropathy. Strong association between RA activity and amyloidosis needs the use of immunosuppressive and combined therapies, to prevent this complication and reduce risk of dialysis. Long-lasting and combined RA pharmacotherapy involves various renal side effects. In this review we describe NSAIDs and DMARDs (Disease-Modifying Antirheumatic Drugs) nephrotoxicity, particularly by gold compounds, D-penicillamine, cyclosporine A and methotrexate. Rare cases of IgA glomerulonephritis during immunomodulating therapy with leflunomide and TNF blocking receptor (etanercept) are reported; real clinical significance of this drug-related nephropathy will be established by development of RA treatment. In RA nephropathies, mesangial glomerulonephritis is the most frequent histological lesion (35-60 % out of biopsies from patients with urinary abnormalities and/or kidney impairment), followed by minimal change glomerulopathy (3-14%) and p-ANCA positive necrotizing crescentic glomerulonephritis. | |
| 15172043 | Treatment of rheumatoid arthritis with etanercept. | 2004 May | Etanercept is effective in the treatment of rheumatoid arthritis (RA)when used as monotherapy and in combination with methotrexate(MTX). Radiographic progression of disease was slowed significantly when the drug was used for a 24-month period and was statistically significantly better than MTX. In addition to its use in RA,etanercept is approved by the U.S. Food and Drug Administration for other rheumatologic conditions, including psoriatic arthritis,ankylosing spondylitis, and juvenile chronic arthritis. | |
| 15188349 | Lymphoma in rheumatoid arthritis: the effect of methotrexate and anti-tumor necrosis facto | 2004 Jun | OBJECTIVE: The risk of lymphoma is increased in patients with rheumatoid arthritis (RA), and spontaneous reporting suggests that methotrexate (MTX) and anti-tumor necrosis factor (anti-TNF) therapy might be associated independently with an increased risk of lymphoma. However, data from clinical trials and clinical practice do not provide sufficient evidence concerning these issues because of small sample sizes and selected study populations. The objective of this study was to determine the rate of and standardized incidence ratio (SIR) for lymphoma in patients with RA and in RA patient subsets by treatment group. Additionally, we sought to determine predictors of lymphoma in RA. METHODS: We prospectively studied 18,572 patients with RA who were enrolled in the National Data Bank for Rheumatic Diseases (NDB). Patients were surveyed biannually, and potential lymphoma cases received detailed followup. The SEER (Survey, Epidemiology, and End Results) cancer data resource was used to derive the expected number of cases of lymphoma in a cohort that was comparable in age and sex with the RA cohort. RESULTS: The overall SIR for lymphoma was 1.9 (95% confidence interval [95% CI] 1.3-2.7). The SIR for biologic use was 2.9 (95% CI 1.7-4.9) and for the use of infliximab (with or without etanercept) was 2.6 (95% CI 1.4-4.5). For etanercept, with or without infliximab, the SIR was 3.8 (95% CI 1.9-7.5). The SIR for MTX was 1.7 (95% CI 0.9-3.2), and was 1.0 (95% CI 0.4-2.5) for those not receiving MTX or biologics. Lymphoma was associated with increasing age, male sex, and education. CONCLUSION: Lymphomas are increased in RA. Although the SIR is greatest for anti-TNF therapies, differences between therapies are slight, and confidence intervals for treatment groups overlap. The increased lymphoma rates observed with anti-TNF therapy may reflect channeling bias, whereby patients with the highest risk of lymphoma preferentially receive anti-TNF therapy. Current data are insufficient to establish a causal relationship between RA treatments and the development of lymphoma. | |
| 11824146 | [Safety aspects of folic acid for the general population]. | 2002 Jan 9 | Periconceptional use of folic acid reduces the risk of neural tube defects considerably. In Switzerland, implementation of these findings could be improved through fortification of a staple food with folic acid. The present paper reviews possible hazards associated with high intake of folic acid in the general population. Among the potential safety issues are interaction between folic acid and zinc, interaction between folic acid and drugs (phenytoin, methotrexate etc.) and hypersensitivity to folic acid. Of main concern are adverse effects of folic acid in cobalamin deficiency. Solutions are discussed. | |
| 11935470 | [Skin nodules and ulcers of the limbs in a patient with rheumatoid arthritis]. | 2002 Apr 5 | CASE HISTORY: While being treated with corticosteroids and methotrexate for rheumatoid arthritis, a 63-year-old man developed livid nodules on his lower arms, hands and feet, as well as fever, necrotizing skin ulcers and rupture of a finger extensor tendon. INVESTIGATIONS: No vasculitis was found in a biopsy of one of the nodules on the lower arm. Fast growing mycobacteria, classified as M. marinum by PCR, were cultured from wound swabs. TREATMENT AND COURSE: The lesions healed on administration of ciprofloxacin, ethambutol and clarithromycin as well as local treatment. CONCLUSION: Cutaneous lesions of an atypical mycobacterial infection are often misdiagnosed. This is especially so in immunocompromised patients and in the differential diagnosis of vasculitis. | |
| 15476202 | The effect of folic acid and folinic acid supplements on purine metabolism in methotrexate | 2004 Oct | OBJECTIVE: To determine if folinic acid supplementation during methotrexate (MTX) therapy for rheumatoid arthritis (RA) reduces both urinary 5-aminoimidazole-4-carboxamide (AICA) and urinary adenosine excretion more than does folic acid supplementation. AICA and adenosine are markers for MTX interference with purine metabolism. METHODS: Forty patients with RA who received MTX for 6 weeks were randomized to receive either daily folic acid or folinic acid supplements during an additional week of MTX therapy. Colorimetric and radioimmunocompetition assays were used to measure 24-hour urinary AICA and adenosine excretion levels, respectively. RESULTS: At the end of 6 weeks, 24-hour urinary levels of AICA, but not adenosine, were elevated as compared with baseline levels (i.e., prior to MTX therapy). Folinic acid, but not folic acid, supplementation normalized urinary AICA levels during MTX therapy. Relatively high urinary levels of AICA were correlated with reduced disease activity. No similar correlations were seen with urinary adenosine levels. CONCLUSION: The blockade of purine nucleotide biosynthesis by MTX at the AICA ribonucleotide transformylase-catalyzed step may be related to the efficacy of MTX, and this blockade is effectively relieved by folinic acid, but not by folic acid, supplementation. | |
| 12074690 | Clinical pharmacokinetics of leflunomide. | 2002 | Leflunomide is the first disease-modifying antirheumatic drug to be approved for rheumatoid arthritis in the past 10 years. Orally administered leflunomide is almost completely converted into its active metabolite A77 1726 (hereafter referred to as M1). M1 displays linear pharmacokinetics at the dosages of leflunomide used in clinical practice. It has a long elimination half-life (approximately 2 weeks), reaching a steady state after approximately 20 weeks. M1 is highly bound to plasma proteins. The pharmacokinetics of M1 are not affected by food intake, and dosage requirements are not influenced by age or gender. Approximately 90% of a single dose of leflunomide is eliminated, 43% in urine, primarily as leflunomide glucuronides and an oxalinic acid derivative of M1, and 48% in faeces, primarily as M1. Elimination can be dramatically increased by using charcoal or cholestyramine. In vitro studies have shown no major influence of leflunomide on the metabolism of analgesics, nonsteroidal anti-inflammatory drugs and methotrexate, drugs usually used in the treatment of rheumatoid arthritis. In clinical studies with a limited number of patients using these drugs concomitantly, no safety problems appeared. Nonspecific inducers of cytochrome P450 (CYP) and some drugs metabolised by CYP2C9 affect the metabolism of M1, and caution should be used in patients cotreated with them. Additional in vitro and in vivo pharmacokinetic studies are needed to better understand the nonenzymatic and enzymatic metabolism of leflunomide. Additional clinical trials should be performed in order to find new indications for leflunomide in other autoimmune diseases, and new combination therapeutic strategies in rheumatoid arthritis. This review is a summary of current knowledge of the pharmacokinetics of leflunomide, focusing primarily on humans and in particular on patients with rheumatoid arthritis. | |
| 15335295 | Considerations with the use of biological therapy in the treatment of rheumatoid arthritis | 2004 Sep | The treatment of rheumatoid arthritis (RA) has changed dramatically over the past 15 years with the realisation that earlier, aggressive therapy limits progression. There is evidence that biological response modifiers (BRMs), which target specific cytokines such as TNF-alpha and IL-1, are more effective than traditional disease-modifying antirheumatic drugs (DMARDs), especially in combination with methotrexate. Four therapies are approved for use in RA; three target TNF-alpha (etanercept [Enbrel, Amgen Inc.], infliximab [Remicade, Centocor Inc.], and adalimumab [Humira, Abbott]), and one targets IL-1 (anakinra [Kineret, Amgen Inc.]). It is clear from both the clinical trials and postmarketing reports that all four agents have a different safety profile compared with traditional DMARDs. There are several areas of concern with the use of the BRMs, which include serious and opportunistic infections, malignancy/lymphoma, congestive heart failure, demyelination, injection/infusion reactions, development of autoantibodies and lupus-like disease. It is important to be fully aware of the safety profile and differences between BRMs in order to use them appropriately. |