Methotrexate in rheumatoid arthritis

Long-term Use of Golimumab in Daily Practice for Patients with Rheumatoid Arthritis

Objective To evaluate the effectiveness and drug retention rate of golimumab (GLM) for long-term use in daily practice for patients with rheumatoid arthritis (RA). Methods Patients with RA who started GLM therapy with a minimum follow-up period of 52 weeks were included. The patients were divided into a biologic-naïve group and switch group. The disease activity score (DAS) 28-erythrocyte sedimentation rate (ESR) (DAS28-ESR), grip power, and Japanese version of the health assessment questionnaire (J-HAQ) score were assessed. In addition, the treatment continuation rate was evaluated at the final follow-up. Patients Sixty-five patients [58 women and 7 men; median (range) age, 69 (61-74) years; median (range) disease duration, 9 (5-16) years] were included. Twenty-eight patients were biologic-naïve (naïve group), and 37 were switched to biologics (switch group). Results The median (range) follow-up period was 134 (58-162) weeks. The DAS28-ESR improved from a median (range) of 4.31 (3.52-5.25) to 2.65 (2.28-3.77) in the naïve group and from 4.27 (3.19-4.89) to 2.89 (2.49-3.88) in the switch group. The grip power improved in both groups (p<0.01); however, the J-HAQ score showed no marked improvement in either group. The continuation rates were 22/28 (78.6%) in the naïve group, and 26/37 (70.3%) in the switch group at the final follow-up. Conclusion We herein report for the first time that the long-term use of GLM improves the grip power. Improving the grip power may help prevent sarcopenia and frailty in the future. Given the efficacy and high continuation rate, we suggest that GLM would be a well-tolerated treatment option for RA.

Analysis of hair and plasma samples for methotrexate (MTX) and metabolite using high-performance liquid chromatography triple quadrupole mass spectrometry (LC-MS/MS) detection

Methotrexate (MTX), a folate antagonist, is the anchor drug used to treat several diseases. Therapeutic effects are attributed to intracellular levels of various methotrexate conjugates that are present in the cell as polyglutamates (MTX-Glu). The present study was conducted to develop a new liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS)-based assay to separately quantitate the MTX-Glu in hair cells, red blood cells, and serum using internal standards. Sample preparation consisted of extraction with an organic solution followed by solid-phase extraction. The presented methodology was applied for the analysis of methotrexate and its polyglutamates in hair cells, red blood cells, and serum obtained from clinical patients. The developed LC-ESI-MS/MS method for the quantitative measurement of MTX-Glu was both sensitive and precise within the clinically relevant range. This method is possibly be superior with respect to sensitivity, selectivity, and speed than all previously described approaches and can be easily applied in routine clinical tests owing to the combination of a simple pretreatment process with robust LC-MS/MS.

A Review of Clinical Applications and Side Effects of Methotrexate in Ophthalmology

Methotrexate (MTX) is a folate analog widely used against a range of diseases including malignancies and autoimmune disorders. Its high effectiveness-price ratio also won extensive application in ophthalmology. On the other hand, although MTX has an excellent pharmacological efficacy, MTX associated side effects in clinical use, which vary from patient to patient, are nonnegligible. There is no comparatively systematic review on MTX associated side effects and its risk factors. This review aimed to reveal novel clinical approaches of MTX and its adverse effects in order to provide a reference for ophthalmic scholars in clinical application of MTX.

Methotrexate an Old Drug with New Tricks

Methotrexate (MTX) is the first line drug for the treatment of a number of rheumatic and non-rheumatic disorders. It is currently used as an anchor disease, modifying anti-rheumatic drug in the treatment of rheumatoid arthritis (RA). Despite the development of numerous new targeted therapies, MTX remains the backbone of RA therapy due to its potent efficacy and tolerability. There has been also a growing interest in the use of MTX in the treatment of chronic viral mediated arthritis. Many viruses-including old world alphaviruses, Parvovirus B19, hepatitis B/C virus, and human immunodeficiency virus-have been associated with arthritogenic diseases and reminiscent of RA. MTX may provide benefits although with the potential risk of attenuating patients' immune surveillance capacities. In this review, we describe the emerging mechanisms of action of MTX as an anti-inflammatory drug and complementing its well-established immunomodulatory activity. The mechanisms involve adenosine signaling modulation, alteration of cytokine networks, generation of reactive oxygen species and HMGB1 alarmin suppression. We also provide a comprehensive understanding of the mechanisms of MTX toxic effects. Lastly, we discussed the efficacy, as well as the safety, of MTX used in the management of viral-related rheumatic syndromes.

Safety, Effectiveness, and Treatment Persistence of Golimumab in Elderly Patients with Rheumatoid Arthritis in Real-World Clinical Practice in Japan

INTRODUCTION

Golimumab has been proven as an effective treatment for rheumatoid arthritis in clinical trials. However, there is a scarcity of data regarding its use in elderly patients in a real-world setting. This study aims to evaluate the safety, effectiveness, and treatment persistence of golimumab in elderly Japanese patients (≥ 75 years) with rheumatoid arthritis.

METHODS

This study was a post hoc analysis of post-marketing surveillance data on 5137 Japanese patients with active rheumatoid arthritis who received golimumab for 24 weeks. The study population was divided into two age groups (younger: < 75 years and elderly: ≥ 75 years), and the safety, effectiveness, and treatment persistence of golimumab were assessed. Also, the reasons for discontinuing golimumab treatment were analyzed by multi-logistic regression.

RESULTS

During golimumab treatment over 24 weeks, younger and elderly groups exhibited comparable improvement of disease activity as measured by EULAR response criteria with similar overall rates of adverse events. However, the survival curve of golimumab for elderly patients was significantly different from that for younger patients due largely to the discontinuation at 4 weeks. The most common reason for discontinuation in elderly patients was patient choice, while it was disease progression in younger patients. Analysis of elderly patients who discontinued treatment by their own decision identified EULAR good response as a factor associated with continuation of golimumab treatment whereas no predictive factor associated with discontinuation was identified.

CONCLUSIONS

The safety and effectiveness of golimumab treatment in elderly Japanese patients aged 75 years or older were comparable to those in younger patients in real-world clinical practice. Analysis of the survival curves suggested that continuous use of golimumab might further improve clinical benefit of golimumab in elderly patients, underpinning the importance of effective communication between physicians and elderly patients based on the treat-to-target strategy.

FUNDING

Janssen Pharmaceutical K.K. and Mitsubishi Tanabe Pharma Corporation.

Real-World Treatment Patterns for Golimumab and Concomitant Medications in Japanese Rheumatoid Arthritis Patients

INTRODUCTION

The aim of this study was to investigate real-world treatment patterns for use of golimumab and concomitant medications in Japanese patients with rheumatoid arthritis.

METHODS

This study was a post hoc retrospective analysis from post-marketing surveillance data on 2350 Japanese patients with moderate/severe rheumatoid arthritis who received golimumab for 24 weeks. The study population was divided based on initiation treatment or dose adjustment patterns with golimumab, methotrexate, or oral glucocorticoids.

RESULTS

Logistic regression analysis revealed that the baseline factors associated with administration of golimumab (100 mg) were higher body weight, failure of prior biological therapy (bio-failure), no previous methotrexate use, and respiratory disease, while previous methotrexate use and absence of renal impairment or respiratory disease were associated with concomitant methotrexate therapy, and previous glucocorticoid use was associated with concomitant glucocorticoid therapy. The following associations were identified with regard to dose adjustment during treatment: bio-failure, no previous methotrexate use, previous csDMARDs use, presence of respiratory disease, allergy history, and higher CRP for golimumab dose escalation; shorter disease duration, previous GC, and no previous methotrexate use for methotrexate dose escalation; no prior biological therapy and renal impairment for methotrexate dose reduction; no previous GC use for glucocorticoid dose escalation; and absence of Steinbrocker's stage II/III/IV, absence of Steinbrocker's class II, no bio-failure, and no previous csDMARDs use for glucocorticoid dose reduction.

CONCLUSIONS

This study revealed that various baseline factors were associated with initiation of treatment and dose adjustment of golimumab, methotrexate, or oral glucocorticoids, reflecting both the treatment strategies of physicians for improving RA symptoms and/or reducing adverse events.

FUNDING

Janssen Pharmaceutical K.K. and Mitsubishi Tanabe Pharma Corporation.

The critical role of macrophages in the pathogenesis of hidradenitis suppurativa

INTRODUCTION

Hidradenitis suppurativa (HS) is a painful chronic inflammatory disease with a prevalence between 1 and 4% of general population. The pathogenesis of HS long eluded scientists, but growing evidence suggests that it is a consequence of inflammatory dysregulation.

FINDINGS

Recent studies suggest that dysregulated immune response to skin flora and overexpression of inflammatory cytokines leads to chronic skin inflammation seen in HS. Macrophages are the most numerous inflammatory cells found in HS infiltrates and release numerous pro-inflammatory cytokines such as IL-23, and IL-1β and TNF-α, exacerbating the inflammation and contributing to the pathogenesis of HS. Furthermore, in HS, there is dysregulated function of other immune players closely associated with macrophage function including: matrix metalloproteases (MMP) 2 and 9 overexpression, toll-like receptor upregulation, impaired Notch signalling, NLRP3 inflammasome upregulation, and dysregulated keratinocyte function. Lifestyle factors including obesity and smoking also contribute to macrophage dysfunction and correlate with HS incidence.

CONCLUSIONS

The overexpression of pro-inflammatory cytokines and subsequent efficacy of anti-cytokine biologic therapies highlights the importance of managing macrophage dysfunction. Future therapies should target key molecular drivers of macrophage dysfunction such as TLR2 and NLRP3 overexpression.

PEG Modified Anticancer Drugs: Synthesis and Biological Activity

Three well known anticancer drugs, doxorubicin, methotrexate and paclitaxel (taxol), have been modified by the permanent attachment of poly(ethylene glycol)(PEG) and evaluated for in vitro cytotoxic activity against murine leukemias P388 and L1210. The relative potencies of the PEG derivatives suggest that modification of antitumor agents with this type of polymer yields compounds that are highly water soluble but less cytotoxic.

Nanoparticle ligand presentation for targeting solid tumors

Among the many scientific advances to come from the study of nanoscience, the development of ligand-targeted nanoparticles to eliminate solid tumors is predicted to have a major impact on human health. There are many reports describing novel designs and testing of targeted nanoparticles to treat cancer. While the principles of the technology are well demonstrated in controlled lab experiments, there are still many hurdles to overcome for the science to mature into truly efficacious targeted nanoparticles that join the arsenal of agents currently used to treat cancer in humans. One of these hurdles is overcoming unwanted biodistribution to the liver while maximizing delivery to the tumor. This almost certainly requires advances in both nanoparticle stealth technology and targeting. Currently, it continues to be a challenge to control the loading of ligands onto polyethylene glycol (PEG) to achieve maximal targeting. Nanoparticle cellular uptake and subcellular targeting of genes and siRNA also remain a challenge. This review examines the types of ligands that have been most often used to target nanoparticles to solid tumors. As the science matures over the coming decade, careful control over ligand presentation on nanoparticles of precise size, shape, and charge will likely play a major role in achieving success.

Synoviocyte apoptosis may differentiate responder and non-responder patients to methotrexate treatment in rheumatoid arthritis

We aimed to evaluate whether methotrexate (MTX) in vitro induces apoptosis in synoviocytes obtained from rheumatoid arthritis patients and whether the apoptosis inducing effect of MTX to synoviocytes is correlated with the clinical responsiveness to MTX in patients with rheumatoid arthritis (RA). We evaluated 18 patients with RA taking MTX 15-20 mg/week as the subject group (nine responders and nine non-responders) and ten patients with osteoarthritis (OA) and nine patients with ankylosing spondylitis (AS) as the control group. Synoviocytes, cultured from the synovial fluid of the knee joint of each subject, were used for experiments between passages 4 and 6, and were treated with MTX. The induction of apoptosis was determined by the quantification of DNA hypoploidy by flow cytometry, nuclear morphology, caspases activation, DNA electrophoresis, and mitochondrial membrane potential measurements. The viability of synoviocytes treated with MTX was different between the MTX responders and nonresponders. MTX induced apoptosis in cultured synoviocytes by mitochondria- and caspase-dependent manners in the MTX responders but did not in the MTX non-responder, OA, and AS patients. The apoptotic responsiveness of the synoviocytes to MTX predicts the sensitivity to MTX treatment and provides a method determine the early application of an anti-tumor necrosis factor-α agent in RA treatment.

Phase II trial of methotrexate in myasthenia gravis

Prednisone is a frequently used treatment for myasthenia gravis (MG) but it has numerous side effects. Methotrexate is a selective inhibitor of dihydrofolate reductase and lymphocyte proliferation and is an effective immuosuppressive medication for autoimmune diseases. Given the negative results of the mycophenolate mofetil study, search for an effective immunosuppressant drug therapy is ongoing. The objective is to determine if oral methotrexate is safe and effective for MG patients who take prednisone. We have initiated a randomized, double-blind, placebo-controlled multicenter trial of methotrexate versus placebo in patients taking at least 10 mg/day of prednisone at enrollment. The methotrexate dose is increased to 20 mg and the prednisone dose is adjusted per protocol during the study. Clinical and laboratory evaluations are performed monthly for 12 months, with the primary efficacy measure being the nine-month prednisone area under the curve (AUC) from months 3 to 12. Secondary outcome measures include MG outcomes, quality of life measures, and a polyglutamation biomarker assay. A total of 18 U.S. sites and 2 Canadian sites are participating, with 48 screened cases, 42 enrolled, with 19 still active in the study.

Trichilia monadelpha bark extracts inhibit carrageenan-induced foot-oedema in the 7-day old chick and the oedema associated with adjuvant-induced arthritis in rats

Trichilia monadelpha (Thonn) JJ De Wilde (Meliaceae) bark extract is used in African traditional medicine for the management of various disease conditions including inflammatory disorders such as arthritis. The present study was undertaken to evaluate the anti-inflammatory properties of aqueous (TWE), alcoholic (TAE) and petroleum ether extract (TPEE) of T. monadelpha using the 7-day old chick-carrageenan footpad oedema (acute inflammation) and the adjuvant-induced arthritis model in rats (chronic inflammation). TWE and TPEE significantly inhibited the chick-carrageenan footpad oedema with maximal inhibitions of 57.79±3.92 and 63.83±12 respectively, but TAE did not. The reference anti-inflammatory drugs (diclofenac and dexamethasone) inhibited the chick-carrageenan-induced footpad oedema, with maximal inhibitions of 64.92±2.03 and 71.85±15.34 respectively. Furthermore, all the extracts and the reference anti-inflammatory agents (diclofenac, dexamethasone, methotrexate) inhibited the inflammatory oedema associated with adjuvant arthritis with maximal inhibitions of 64.41±5.56, 57.04±8.57, 62.18±2.56%, for TWE, TAE and TPEE respectively and 80.28±5.79, 85.75±2.96, 74.68±3.03% for diclofenac, dexamethasone and methotrexate respectively. Phytochemical screening of the plant bark confirmed the presence of a large array of plant constituents such as alkaloids, glycosides, flavonoids, saponins, steroids, tannins and terpenoids, all of which may be potential sources of phyto-antiinflammatory agents. In conclusion, our work suggests that T. monadelpha is a potential source of antiinflammatory agents.

Associations between methotrexate treatment and methylenetetrahydrofolate reductase gene polymorphisms with incident fractures in Japanese female rheumatoid arthritis patients

Several case reports have described associations between pathological nonvertebral fractures and low-dose methotrexate (MTX) in rheumatoid arthritis (RA) patients. Furthermore, a significant association between the C677T polymorphism in the methylenetetrahydrofolate reductase (MTHFR) gene and incident fractures has been reported in postmenopausal women. We attempted to determine whether MTX use and MTHFR polymorphisms are associated with incident fracture risk in Japanese female RA patients. DNA samples, laboratory data, and clinical data were obtained from 731 female RA patients more than 50 years old as part of the Institute of Rheumatology Rheumatoid Arthritis (IORRA) observational cohort study. Genotyping of the MTHFR polymorphisms C677T and A1298C was performed using TaqMan SNP Genotyping Assays. MTX use, MTHFR polymorphisms, and other potential risk factors predictive of fracture were analyzed by Cox proportional hazards regression models, including time-dependent covariates. During 78 months from October 2000 to March 2007, 25 and 90 patients developed vertebral and nonvertebral fractures, respectively. Patients with nonvertebral fractures were more likely to take MTX (P = 0.011; odds ratio, 1.77; 95% confidence interval, 1.13-2.76) compared to patients without fractures. Although the C677T and A1298C polymorphisms were not significantly associated with incident fracture risk, MTX use, age, disease duration, and Japanese health assessment questionnaire score were significantly (P < 0.05) and independently associated with nonvertebral fracture incidence. Our results suggest that MTX use is associated with a nonvertebral fracture risk, whereas MTHFR polymorphism status does not appear to be a clinically useful marker for predicting fracture risk in Japanese female RA patients.

Recommendations for the use of methotrexate in juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is one of the most common rheumatic diseases in childhood. In a significant number of JIA cases the disease is resistant to therapy with NSAIDs, intra-articular corticosteroid injections, and physiotherapy, and methotrexate is used as a second-line agent. The efficacy of methotrexate therapy in children with JIA has been demonstrated in prospective controlled trials and this agent appears to have slightly superior efficacy compared with leflunomide. Data from randomized studies indicate a starting dose of 10-15 mg/m(2)/week orally. The dose of parenteral methotrexate can be increased to 15-20 mg/m(2)/week. Combination therapy with methotrexate and an NSAID is recommended. However, there are still no data on when to initiate methotrexate in JIA and how long children should be treated. The most common adverse effects are aversion to the drug and nausea. In the case of minor adverse effects the use of folic acid at a dosage of 1 mg/day is feasible. In JIA, daily folate supplementation has only been studied in one small heterogeneous cohort with a very short observation period and, at present, a general recommendation on daily folate supplementation cannot be made. In summary, methotrexate is seen by many pediatric rheumatologists as the first-choice, second-line drug; there is good evidence of its efficacy in JIA. However, in light of the recent introduction of biologic agents, the place of methotrexate in the treatment of JIA may have to be redefined in the coming years.

Etanercept in severe active rheumatoid arthritis: first Australian experience

BACKGROUND

Etanercept reduces disease activity in adults with chronic rheumatoid arthritis (RA) who are resistant to other therapies. Medicare Australia Pharmaceutical Benefit Scheme subsidized treatment (since August 2003) restricts etanercept availability to a most drug-resistant RA population. The aim of the study was to assess the efficacy of etanercept in this unique group after 12 months of therapy.

METHODS

A prospective study of the first 50 consecutive private practice, adult RA patients whom were commenced on etanercept. The primary efficacy measures included short form 36 scores, Disease Activity Score 28, American College of Rheumatology (ACR) response improvement in per cent and the ACR individual core set components at baseline, 3 and 12 months. Analysis was by intention to treat.

RESULTS

There was significant improvement in all mean short form 36 component scores (P < 0.05) and all ACR core set component scores (P < 0.05) comparing 12 months to baseline. The disease activity score 28 also significantly fell from baseline at both 3 and 12 months (P < 0.05). The ACR 20% response significantly improved (P < 0.05) both at baseline to 3 months 92% (81.2, 96.9) and to 12 months 80% (67.0, 88.8). Serious adverse events occurred in 16%. At 12 months 88% completed treatment.

CONCLUSION

Etanercept therapy will, by 3 and 12 months, significantly improve the short form 36, disease activity score 28, ACR 20% response and core set components. Our results are similar to international studies using etanercept in efficacy and tolerance despite our cohort being more resistant to preceding drug therapy. Etanercept offers this unique active severe refractory late RA Australian population a new therapeutic option to control their disease.

Cytokine profiles in peripheral blood and whole blood cell cultures associated with aggressive periodontitis, juvenile idiopathic arthritis, and rheumatoid arthritis

BACKGROUND

Cytokines play a key role in the pathogenesis of inflammatory diseases. An obvious question is whether patients with aggressive periodontitis, juvenile idiopathic arthritis, or rheumatoid arthritis share blood cytokine profiles distinguishing them from individuals free of disease.

METHODS

The study population consisted of Danish white adults, <35 years of age, diagnosed with localized aggressive periodontitis (LAgP; N = 18), generalized aggressive periodontitis (GAgP; N = 27), juvenile idiopathic arthritis (JIA; N = 10), or rheumatoid arthritis (RA; N = 23) and healthy individuals with no systemic or oral diseases (control [CTRL]; N = 25). Enzyme-linked immunosorbent assays were used to determine the levels of interleukin (IL)-1alpha, IL-1beta, IL-1 receptor antagonist (IL-1Ra), IL-6, IL-10, tumor necrosis factor (TNF)-alpha, and lymphotoxin (LT)-alpha in peripheral blood (plasma) and unstimulated and stimulated whole blood cell cultures from the same blood collection. Autoantibodies (aAb) to IL-1alpha and IL-6 were quantitated by radioimmunoassay.

RESULTS

Similar patterns of slightly higher IL-10 levels in plasma were found for GAgP and RA patients and in unstimulated cultures for GAgP, RA, and JIA patients. Interestingly, unstimulated cultures also demonstrated similar patterns of higher TNF-alpha levels for these three groups of patients. Similar group patterns of periodontitis patients (LAgP and GAgP) included increased IL-1Ra levels in stimulated cultures, which also showed similar group patterns of arthritis patients (JIA and RA) with respect to higher IL-1alpha and lower LT-alpha levels. Low titers of aAb to IL-1alpha and IL-6 were found in almost all individuals.

CONCLUSION

Patients with aggressive periodontitis and types of arthritis presented with similar components of blood cytokine profiles distinguishing them from individuals free of disease.

Synthesis of oligotuftsin-based branched oligopeptide conjugates for chemotactic drug targeting

The synthesis and chemotactic properties of a new class of branched oligopeptide-based conjugates are described. Tetratuftsin derivatives containing chemotactic formyl tripeptides (For-MLF, For-NleLF or For-MMM) in branches were prepared by stepwise solid-phase peptide synthesis. The influence of the composition and ionic charge of the carrier-branched oligopeptide on the chemotactic behaviour of the conjugate was studied in Tetrahymena pyriformis. Conjugates with methotrexate (Mtx) as a drug component was also prepared. For this, a GFLGC spacer, cleavable by cathepsin B, was used. The spacer with N-terminal methotrexate was coupled to the chloroacetylated chemotactic carrier molecule by thioether bond formation. The chemotactic activity and cytotoxity of Mtx conjugates were also studied.

Evidence-based use of methotrexate in children with rheumatic diseases: a consensus statement of the Working Groups Pediatric Rheumatology Germany (AGKJR) and Pediatric Rheumatology Austria

Juvenile idiopathic arthritis (JIA) is the most common diagnosis in children and adolescents with rheumatic disorders. In many children and adolescents, JIA is successfully treated with non-steroidal anti-inflammatory drugs (NSAID) and physiotherapy. However, in a significant number of cases the disease is resistant to this therapy, and treatment with "second line" disease-modifying antirheumatic drugs (DMARDs) is required. Methotrexate (MTX) is frequently referred to as "first-choice second-line agent" for the treatment of JIA. To increase drug safety, the Working Groups for Children and Adolescents with Rheumatic Diseases in Germany (AGKJR) and Pediatric Rheumatology Austria have initiated the formulation of evidence-based recommendations. Evidence is based on consensus expert meetings, a MEDLINE search with the key words "Methotrexate" and "juvenile arthritis" limited to age 0-18 years, standard textbooks and review articles, data from the central registry of the German Research Center for Rheumatic Diseases (Deutsches Rheumaforschungszentrum Berlin DRFZ), experience with MTX in adults with rheumatoid arthritis (RA), and recommendations of the German Society of Rheumatology (DGRh). Based on these data, evidence and recommendations are graded, and evidence-based recommendations for the use of MTX in children and adolescents with rheumatic disease are presented.

Effect of MX-68 on airway inflammation and hyperresponsiveness in mice and guinea-pigs

MX-68 is a newly synthesized antifolate, which is a derivative of methotrexate (MTX). In this paper, the effect of MX-68 on allergic airway responses in mice and guinea-pigs was studied. In the first experiment, antigen-induced airway inflammation and airway hyperresponsiveness (AHR) to acetylcholine in mice were examined and compared with the effects of classical antifolate methotrexate and prednisolone. Mice were sensitized with ovalbumin as an antigen and challenged with ovalbumin inhalation three times. After the last inhalation, AHR and airway inflammation were observed. An increase in Th2 cytokines (IL-4 and IL-5) and a decrease in a Th1 cytokine (IFN-gamma) in the bronchoalveolar lavage fluid (BALF), as well as an elevation of the immunoglobulin level in serum, were observed in sensitized mice. Oral administration of MX-68 had no effect on changes of body weight, but prednisolone reduced body weight during the experiment. The antigen-induced AHR and increases in the number of eosinophils and lymphocytes in BALF were significantly inhibited by MX-68. MX-68 interfered with the elevation of IL-4 and IL-5 levels in BALF, but had no effect on the decrease in IFN-gamma. Moreover, MX-68 significantly inhibited the elevation of serum IgE and IgG levels. In the guinea-pig model for bronchial asthma, biphasic increases in airway resistance (immediate asthmatic response, IAR, and late asthmatic response, LAR), as well as accumulated inflammatory cells in BALF, were observed after repeated antigen challenge. These asthmatic responses and inflammatory signs were significantly decreased by administration of MX-68. These results suggest that MX-68 obviously has an anti-inflammatory effect in an animal model of asthma and would be useful clinically for the treatment of bronchial asthma.

Pharmacogenetics of disease-modifying anti-rheumatic drugs

The outcome of treatment with disease-modifying anti-rheumatic drugs (DMARDs) in rheumatoid arthritis (RA) patients is considerably variable and is also unpredictable. It would be useful clinically if physicians were able to predict responses to DMARDs prior to their administration. One possible cause of differences in efficacy and adverse drug reactions is genetic variation in how individuals metabolize drugs. Based on pharmacogenetics, tailor-made drug therapy, also called personalized drug therapy or individual drug therapy, will be possible with analysis of genetic polymorphism, such as single nucleotide polymorphism (SNP), and analysis of haplotype and diplotype configuration. Several studies of the correlation between the genetic polymorphism of enzymes metabolizing several DMARDs and efficacy or adverse drug reactions have already been reported, suggesting that pharmacogenetics will be applicable to the treatment of RA in the near future.

Effect of methotrexate on Th1 and Th2 immune responses in mice

We investigated the effect of the anti-rheumatic drug methotrexate (MTX) on Th1 and Th2 immune responses in mice. For this investigation, mice were immunized subcutaneously at the base of the tail with ovalbumin (OVA) emulsified with complete Freund's adjuvant (day 0). Varying doses of MTX were orally administered daily from days 0 to 20. On day 21, anti-OVA IgG2a and interferon-gamma (IFN-gamma) as indicators of Th1 responses and anti-OVA IgG1 and interleukin-10 (IL-10) as those of Th2 responses were measured. The results showed that treatment with MTX was followed by decreases in OVA-specific IgG and proliferation of spleen cells to the antigen. The anti-rheumatic drug inhibited both anti-OVA IgG2a and IgG1 production, although the inhibitory effect of MTX on the antigen-specific IgG2a production appeared to be greater than that on IgG1 production. IFN-gamma, but not IL-10, secretion was markedly downregulated by MTX. Administration of MTX resulted in suppression of antigen (OVA)-induced arthritis in mice. The suppression of the joint inflammation by MTX was associated with inhibition of OVA-specific proliferative responses of spleen cells, anti-OVA IgG, IgG2a and IgG1 production, and IFN-gamma and IL-10 secretion, although more pronounced decreases in IgG2a and IFN-gamma were observed compared with those in IgG1 and IL-10 in MTX-treated mice. These results indicate that MTX appears to suppress Th1 and, to a lesser extent, Th2 immune responses and its anti-arthritic effect on human rheumatoid arthritis might be at least in part explained by down-regulation of Th1 responses involved in the disease.

Drug targeting by macromolecules without recognition unit?

his review will summarize available information on the ability of macromolecular conjugates containing no specific recognition motifs to deliver anthracyclines (daunomycin, adriamycin) or methotrexate to target cells such as tumour cells or macrophages. Conjugates with natural (proteins, DNA, carbohydrates) and synthetic macromolecules (linear and branched chain poly-alpha-amino acids, non-biodegradable DIVEMA, HPMA etc.) will be reviewed. Experimental data from several laboratories indicate that these conjugates are taken up by cells mainly by fluid-phase or adsorptive endocytosis. It is believed that these processes do not involve 'specific receptors'. Two examples of methotrexate and daunomycin conjugates will be discussed to show the effect of the chemical structure of branched chain polypeptides on the uptake and antitumour or antiparasitic (Leishmania donovani infection) efficacy of conjugates.

Etanercept added to background methotrexate therapy in patients with rheumatoid arthritis: continued observations

OBJECTIVE

To observe the long-term safety and efficacy of combination therapy with etanercept and methotrexate in patients with rheumatoid arthritis (RA), and to determine whether the addition of etanercept allowed reductions in methotrexate or corticosteroid dosages while maintaining a clinical response.

METHODS

Patients with RA who received methotrexate plus etanercept in a previous randomized, placebo-controlled trial were offered the opportunity to enroll in an open-label extension study for further evaluation of treatment with etanercept and methotrexate.

RESULTS

Seventy-nine of the 89 patients in the original blinded study enrolled in the extension study, and 65 of these patients continue in the study. Patients have received etanercept therapy for up to 47 months (median 44 months). The types and rate of adverse events noted during the extension trial were similar to those observed in the controlled trial. At the 3-year assessment, 77% of the 57 patients available for evaluation met American College of Rheumatology 20% (ACR20) criteria for improvement in RA, 47% met the ACR50 criteria, and 23% met the ACR70 criteria. Of the 36 patients assessed at 3 years in the extension study, 30 (83%) were able to decrease their dosages of corticosteroids, and 20 (56%) were able to discontinue corticosteroid therapy. At 3 years, the dosage of methotrexate was decreased in 41 of 66 patients (62%), and methotrexate therapy was discontinued in 19 patients (29%).

CONCLUSION

In this observational continuation study, the addition of etanercept to background methotrexate provided sustained clinical benefit over a median period of 44 months. With etanercept therapy, there were trends toward dosage reduction or discontinuation of methotrexate and corticosteroids, without apparent worsening of ACR response rates. Compared with the controlled trial, no increases in the rate of adverse events were observed.

Light and electron microscopic analysis of liver biopsy samples from rheumatoid arthritis patients receiving long-term methotrexate therapy

OBJECTIVE

We study liver damage in forty-two patients with rheumatoid arthritis (RA) using light (LM) and electron microscopy (EM) and assess histological changes after four years of treatment with methotrexate (MTX).

PATIENTS AND METHODS

liver biopsies (LB) were taken before and after four years of treatment. Patients received weekly doses of between 7.5-15 mg of MTX.

RESULTS

Fourteen per cent of the baseline LB presented mild perisinusoidal fibrosis (Roenigk IIIA) and the rest a lower Roenigk grade; EM identified an increase in collagen fibers in the Disse spaces in 50% of baseline LB. Neither microscopy technique revealed histological progression in any of the sequential LB. Variables that correlated with histological abnormalities were patient's age, length of evolution of the disease, alcohol consumption and biochemical data (gammaglutamate transferase and albumin); the cumulative dose of MTX was not correlated with worse histological findings. Correlation between the two microscopy techniques was good, though EM was more sensitive than LM for the detection of fibrosis.

CONCLUSIONS

RA patients present with liver damage before treatment with MTX. The alterations are mild. At low doses MTX treatment is safe. In addition to the recommendations of the American College of Rheumatology, other factors associated with liver impairment are patient's age and length of evolution of the RA.

Transcriptional downregulation of ORF50/Rta by methotrexate inhibits the switch of Kaposi's sarcoma-associated herpesvirus/human herpesvirus 8 from latency to lytic replication

Kaposi's sarcoma-associated herpesvirus (KSHV) encodes a cellular dihydrofolate reductase (DHFR) homologue. Methotrexate (MTX), a potent anti-inflammatory agent, inhibits cellular DHFR activity. We investigated the effect of noncytotoxic doses of MTX on latency and lytic KSHV replication in two KSHV-infected primary effusion lymphoma cell lines (BC-3 and BC-1) and in MTX-resistant BC-3 cells (MTX-R-BC-3 cells). Treatment with MTX completely prevented tetradecanoyl phorbol acetate-induced viral DNA replication and strongly decreased viral lytic transcript levels, even in MTX-resistant cells. However, the same treatment had no effect on transcription of cellular genes and KSHV latent genes. One of the lytic transcripts inhibited by MTX, ORF50/Rta (open reading frame), is an immediate-early gene encoding a replication-transcription activator required for expression of other viral lytic genes. Therefore, transcription of genes downstream of ORF50/Rta was inhibited, including those encoding the viral G-protein-coupled receptor (GPCR), viral interleukin-6, and K12/kaposin, which have been shown to be transforming in vitro and oncogenic in mice. Resistance to MTX has been documented in cultured cells and also in patients treated with this drug. However, MTX showed an inhibitory activity even in MTX-R-BC-3 cells. Two currently available antiherpesvirus drugs, cidofovir and foscarnet, had no effect on the transcription of these viral oncogenes and ORF50/Rta. MTX is the first example of a compound shown to downregulate the expression of ORF50/Rta and therefore prevent viral transforming gene transcription. Given that the expression of these genes may be important for tumor development, MTX could play a role in the future management of KSHV-associated malignancies.

Polymorphisms in the methylenetetrahydrofolate reductase gene were associated with both the efficacy and the toxicity of methotrexate used for the treatment of rheumatoid arthritis, as evidenced by single locus and haplotype analyses

5,10-Methylenetetrahydrofolate reductase (MTHFR), a key enzyme involved in folate metabolism, has two common polymorphisms that affect enzyme activity. The objective of this study was to examine whether there was a correlation between the genotype or haplotype of the MTHFR gene and the efficacy or toxicity of methotrexate (MTX) in the treatment of rheumatoid arthritis. MTX-treated rheumatoid arthritis patients (n = 106) were selected from outpatient clinics and used for a retrospective study to examine the correlation between genotypes or haplotypes concerning polymorphisms of the MTHFR gene, and the efficacy or toxicity of MTX. Estimation of the haplotype frequencies was performed by maximum likelihood estimation based on expectation maximization algorithm. Single locus analysis examining each locus separately showed that patients with 1298C were receiving significantly lower doses of MTX compared to patients without [P < 0.05, relative risk (RR) = 2.18, 95% confidence interval (CI) 1.17-4.06], while a higher rate of overall MTX toxicity was observed in patients with 677T than those without (P < 0.05, RR = 1.25, 95% CI 1.05-1.49). An estimation of haplotype frequencies showed that there was no 677T-1298C haplotype in the population. Posterior distribution of the diplotype configuration for each individual was concentrated on a single configuration. Patients with the 677C-1298C haplotype were receiving lower doses of MTX than those without (P < 0.05, RR = 2.14, 95% CI 1.13-4.07), while subjects with 677T-1298A had a higher frequency of side-effects from MTX (P < 0.05, RR = 1.42, 95% CI 1.11-1.82). Both single locus and haplotype analyses suggest that polymorphisms within the MTHFR gene are associated with both the efficacy and toxicity of MTX in rheumatoid arthritis patients. Pharmacokinetic studies are necessary to prove the association.

Drug consumption in the first years of rheumatoid arthritis in France, The Netherlands, and Norway. A longitudinal study in the early nineties

OBJECTIVE

To analyse drug consumption in the first years of rheumatoid arthritis (RA) in France, the Netherlands, and Norway, in a longitudinal study between 1991 and 1993.

PATIENTS AND METHODS

The EURIDISS cohort followed up over three years included 695 RA subjects with less than 5 years disease duration. Clinical and biological parameters, drug consumption according to ATC classification, and use of local treatment were recorded.

RESULTS

In the Netherlands consumption of second-line treatment occurred early on, and remained constant over time. In France, it was consumed by half of the subjects and decreased during follow-up (p<0.001). In Norway, 50% of the subjects were on second-line treatment at the outset. NSAIDs rather than corticoids were the most widely consumed. Patients underwent frequently local treatments with decrease frequency of infiltrations over time (p<0.001).

CONCLUSION

Second-line treatments were used in the first years of disease development, following varying sequences in the different countries.

Hepatic effects of long-term methotrexate use in the treatment of inflammatory bowel disease

OBJECTIVE

Methotrexate is currently used as a treatment for refractory inflammatory bowel disease. This study sought to evaluate the hepatic effects of long-term methotrexate therapy in patients with inflammatory bowel disease and to determine whether the established guidelines for monitoring methotrexate-related hepatotoxicity with surveillance liver biopsy in patients with psoriasis or rheumatoid arthritis are applicable to these patients.

METHODS

Thirty-two patients with inflammatory bowel disease receiving cumulative methotrexate doses of > or = 1500 mg were studied. Liver chemistry tests were obtained before and during therapy. Twenty patients underwent liver biopsies as recommended for methotrexate-treated patients with psoriasis; the biopsies were reviewed and graded according to Roenigk's criteria for methotrexate-induced hepatotoxicity (a grading system for methotrexate hepatotoxicity in psoriasis patients) by a liver pathologist blinded to the methotrexate dose.

RESULTS

In patients who had liver biopsies, the mean cumulative methotrexate dose was 2633 mg (range, 1500-5410 mg), given for a mean of 131.7 wk (range, 66-281 wk). Nineteen of 20 patients (95%) had mild histological abnormalities (Roenigk's grade I and II), and one patient had hepatic fibrosis (Roenigk's grade IIIB). Abnormal liver chemistry tests, present in 6 of 20 (30%) patients, did not identify the patient with Roenigk's grade IIIB hepatotoxicity.

CONCLUSIONS

Cumulative methotrexate doses up to 5410 mg given up to 281 wk in patients with inflammatory bowel disease are associated with little hepatotoxicity. Surveillance liver biopsies based on cumulative methotrexate doses are not warranted in these patients.

Central administration of methotrexate reduces mechanical allodynia in an animal model of radiculopathy/sciatica

We have recently reported that injury to a lumbar root in a rat model of radiculopathy produces spinal glial activation associated with elevated proinflammatory cytokines. Based on our hypothesis that central neuroinflammatory processes may manifest clinically as radicular pain, we undertook pharmacological intervention using the immunosuppressive agent methotrexate (MTX). The L5 lumbar spinal root (central to the dorsal root ganglia) was exposed unilaterally and loosely constricted with chromic gut. In the prevention (phase I) study, MTX was administered intrathecally (1 mg/kg) and around the spinal root (1 mg/kg) at surgery and at days 2 and 4 postsurgery (group A). Saline injection was employed for the control group (group B). Sham operated animals were administered MTX to determine the potential for behavioral/neural side effects (group C). In the existing pain paradigm (phase II) study, the experiment was extended to day 14 with three additional groups. The same dose and method of delivery of MTX or saline was administered as in phase I in the first week on days 0, 2, and 4 and in the second week on days 7, 9, and 11 postsurgery. To measure the effects of MTX on existing behaviors saline was administered in the first week and MTX during the second (group D; Saline:MTX). The control group received saline during both weeks (group E; Saline:Saline). To examine the possible recurrence of radicular pain after MTX termination, MTX was given in the first week and saline in the second (group F; MTX:Saline). Gait disturbance and mechanical allodynia (using von Frey filaments) were assessed up to day 7 in the prevention study (Phase I) and day 14 in the existing pain paradigm (Phase II). The L5 spinal cord segments were harvested for assessment of immunohistochemical glial activation using the antibodies OX-42 (microglial marker) and glial fibrillary acidic protein (GFAP: astrocytic marker) and for the presence of Major Histocompatibility Complex (MHC) Class II expression. Group C (Sham+MTX) did not demonstrate any evidence of gait disturbance or mechanical allodynia after MTX administration. The rats in group B (Surgery+Saline) demonstrated mechanical allodynia from one day postsurgery to the time of euthanization. When allodynia was assessed using the 12 g von Frey filament, the MTX treated rats in group A showed significantly decreased mechanical allodynia as compared to the saline treated rats (group B) (repeated measured ANOVA, P<0.0001). In the phase II study, the rats in group D (Saline:MTX) and E (Saline:Saline) showed robust allodynia in the first week after the surgery. In the second week, mechanical allodynia significantly decreased in group D, while mechanical allodynia continued in the saline treated group (repeated measured ANOVA, P=0.0121). Allodynia was significantly attenuated in group F (MTX: Saline) as compared to the response in groups D and E at day 7 (one-way ANOVA, P<0.0001) and remained significantly lower as compared to group E up to day 11 postsurgery (one-way ANOVA, P9=0. 0013: P11=0.0048). OX-42 and GFAP expression were elevated in the gray matter of the L5 spinal section in all groups that underwent the root ligature with chromic gut (Groups A, B, D-F). There were no significant differences in glial activation between the groups. However, spinal expression of MHC II was markedly reduced in the MTX treated group as compared with the saline treated group. The exact mechanism of action of MTX in attenuating mechanical allodynia has not yet been elucidated. The present results indicate that MTX administration may offer a new treatment modality for radicular pain with or without disc herniation as well as directing new research into the development of novel immunomodulators for the treatment of chronic neuropathic and radicular pain.

Interleukin-1beta (IL-1beta) inhibition: a possible mechanism for the anti-inflammatory potency of liposomally conjugated methotrexate formulations in arthritis

1. Liposomes with conventional and long-circulation times were employed as carriers for the methotrexate derivative MTX-gamma-DMPE (MTX-EPC and MTX-PEG respectively), their mechanism of action was investigated in vitro and in vivo and their therapeutic efficacy assessed using the rat collagen-induced arthritis (CIA) model. 2. At non-toxic dose, both MTX-EPC and MTX-PEG inhibited the lipopolysaccharide (LPS) induced release of IL-1beta from activated rat peritoneal macrophages (rPMPhi) in a dose and time dependent manner. Free methotrexate (MTX) was not active in this respect. After a single intravenous injection (i.v.), and at equivalent doses, both free MTX (500 microg) and MTX-EPC inhibited the LPS induced rise in plasma IL-1beta levels observed in MTX-PEG and saline treated rats. 3. When used to treat established CIA, MTX-EPC resulted in significantly lower clinical score (CS) (1.0+/-0.42 (P<0.001)) and hind paw diameter (HPD) (6.5+/-0.34 mm (P<0.001)) measurements than controls (3.0+/-0.26; 7.33+/-0.41 mm), after only two i.v. doses, and remained significantly lower for the entire experimental period. By day 24 both CS (2+/-0.61 (P<0.001)) and HPD (6.97+/-0.25 mm (P<0.002)) measurements had also become significantly lower in MTX-PEG treated rats than in saline treated controls (3.62+/-0.17, 7. 92+/-0.38 mm) and remained lower until day 30. Joint inflammation in MTX treated rats was completely ameliorated by day 20 but the health and well being of the animals was compromised and the experiment terminated at this time-point. 4. Our results clearly demonstrate that both MTX-EPC and MTX-PEG liposomes have potential for development into therapeutic modalities for the treatment of inflammatory joint disease in man.

Selective expression of folate receptor beta and its possible role in methotrexate transport in synovial macrophages from patients with rheumatoid arthritis

OBJECTIVE

To investigate the expression of folate receptors (FR) and reduced folate carrier (RFC) and determine their relevance to methotrexate (MTX) transport in synovial mononuclear cells (SMC) from patients with rheumatoid arthritis (RA).

METHODS

Levels of FR and RFC messenger RNA (mRNA) were examined by reverse transcriptase-polymerase chain reaction (RT-PCR) in SMC from RA patients and peripheral blood mononuclear cells from healthy donors. Expression of FR-beta mRNA and protein was determined by Northern blot and Western blot analyses in RA SMC and monocyte/macrophage-lineage cells. FR-beta expression and folic acid binding capacity on the cell surface were examined by flow cytometric analysis and 3H-folic acid binding analysis. Studies of the inhibition of 3H-MTX uptake in the presence of unlabeled folic acid were performed to investigate the uptake of MTX through FR in RA SMC.

RESULTS

RT-PCR, Northern blot, and Western blot analyses showed that FR-beta mRNA and protein were expressed selectively in activated monocytes and CD14+ RA SMC. These cells exhibited folic acid binding capacity. Furthermore, the FR-beta protein was shown to have folic acid binding capacity. Uptake of 3H-MTX through RA SMC was significantly inhibited in the presence of unlabeled folic acid.

CONCLUSION

These results demonstrate that FR-beta expression is selectively elevated in RA synovial macrophages and suggest that MTX is transported through FR-beta in RA synovial macrophages. The findings suggest that folate antagonists with higher affinity for FR-beta would be useful in the treatment of RA.

Pulmonary function changes in patients with psoriasis on methotrexate therapy

Methotrexate is known to induce pulmonary fibrosis. The present study was undertaken to assess pulmonary toxicity, if any, in psoriasis patients on methotrexate therapy and correlate the dose and duration of the treatment with any changes in pulmonary function. Ten patients who had taken methotrexate for one year and ten patients receiving methotrexate were included in the present study. Detailed lung function studies including arterial blood gas analysis were carried out. In both groups, the only pulmonary function abnormalities detected were FEF200-1200, FEF25-75%, residual volume (RV), and RV/TLC%, which showed a decline after six months of treatment. However, this was not significant. No changes were detected in the arterial blood gas values following methotrexate therapy. Therefore, the present study did not find any significant deterioration of lung functions in psoriasis patients on methotrexate therapy.

The scarring processes in mucosal tissues after immune injury

OBJECTIVES

An important feature of the healing processes is scar formation which may be necessary for organism survival. If it proceeds to the pathological state, it may impair normal function. The purpose of this review is to focus on some of the factors that may influence this process after immune injury, comparing it in the skin and mucosa.

METHODS

A detailed literature search of peer-reviewed journals was conducted. Studies reported in all languages considered relevant and important were used, including humans, animals, and tissue culture.

RESULTS

Analysis of the data indicate that the scarring process is mainly dependent on (1) the type of the lesion, (2) the cause and duration of injury, and (3) the tissue involved and its microenvironment. Equally important is the large spectrum and heterogenicity in the biological activity of fibroblasts and their role in scar formation.

CONCLUSIONS

The process of scar formation is complex and multistep process and is affected and influenced by local and systemic factors. Although it appears irreversible, there are pharmacological agents available, and under investigation, that may minimize its detrimental effects.

Methotrexate in patients with Crohn's disease after 6-mercaptopurine

OBJECTIVE

The objective of this study was to describe the clinical outcome of children with Crohn's disease treated with subcutaneous methotrexate.

SUBJECTS/METHODS

Fourteen patients (10 boys) with extensive Crohn's disease diagnosed at a mean age of 10.6 +/- 3.6 years had previously received various medical therapies for 4.3 +/- 4.0 years. Because of the severity of their disease, 6-mercaptopurine had been introduced but discontinued because of the patients' failure to respond (n = 11) or the development of pancreatitis (n = 3). Subsequently, low-dose, weekly, subcutaneous methotrexate was initiated. Pediatric Crohn's Disease Activity Index scores and prednisone requirement were followed as outcome measures.

RESULTS

Overall, 9 (64%) of the 14 patients showed improvement, including 6 (55%) of 11 patients who had previously received an adequate trial of 6-mercaptopurine and all three patients who were intolerant of 6-mercaptopurine. Improvement in clinical and laboratory measures occurred by 4 weeks and were similar whether (n = 8) or not (n = 6) the dose of corticosteroids was increased before the start of subcutaneous methotrexate. Three patients were tapered from their initial methotrexate dose after the minimization of corticosteroids and remain well. One patient receiving daily corticosteroids died suddenly after acute onset of illness. Among patients responding, methotrexate was discontinued because of side effects (n = 2) or electively (n = 2). Of the latter two patients, one has resumed methotrexate after disease relapse, whereas the other patient has had a sustained remission.

CONCLUSIONS

Low-dose, weekly, subcutaneous methotrexate can induce remission in some pediatric patients with Crohn's disease who fail to adequately respond to other immunomodulator medications.

Methotrexate in rheumatoid arthritis: an update with focus on mechanisms involved in toxicity

OBJECTIVES

To provide an update of the current knowledge of the mechanism of action of low-dose methotrexate (MTX) in the treatment of patients with rheumatoid arthritis (RA), with an emphasis on the mechanisms involved in toxicity. We also considered strategies currently used to prevent or decrease toxicity of MTX.

METHODS

We reviewed the literature dealing with the subjects of MTX treatment of RA, the mechanisms of action of low-dose MTX regarding efficacy and toxicity, and strategies used to prevent or decrease MTX toxicity.

RESULTS

MTX is a fast working and effective second-line antirheumatic agent (SLA). Its use is limited mainly because of side effects. The mechanisms of action regarding efficacy and toxicity are probably determined by different metabolic pathways. Recent data indicate that the antiinflammatory effect of MTX is mediated by adenosine. However, MTX side effects can only partly be explained by folate antagonism and may also depend on its action on other related metabolic pathways. The latter include the homocysteine-methionine-polyamine pathway and purine metabolism. Variants in these metabolic routes (ie, the C677T mutation in the methylene-tetrahydrofolate reductase [MTHFR] gene), may predispose to the development of side effects. Currently the most promising strategy to decrease or prevent toxicity of MTX is concomitant prescription of folic acid or folinic acid. Other strategies are currently under investigation.

CONCLUSIONS

MTX benefits a majority of RA patients. Approximately 30% of patients, however, abandon treatment because of drug-related side effects. Folic acid or folinic acid likely reduces MTX toxicity. More data, however, are needed to evaluate a potential detrimental effect on the antirheumatic efficacy of MTX.

Does methotrexate increase the risk of infection or malignancy?

Most patients do not exhibit overt signs of immunosuppression. Studies cited in this article support a modest increase in the rate of bacterial respiratory and skin infections. Opportunistic infections occur rarely, however, and may be life threatening. The case for MTX carcinogenicity is less clear. The risk for malignancy other than lymphoproliferative disorders does not seem to be elevated, although multiple sporadic malignancies have been reported in treated patients. MTX is a superb agent for the therapy of a large group of immune-mediated diseases. Although an increased risk for infection and possible malignancy exists, the risk is small compared with the potential clinical benefit.