Low-dose methotrexate spares steroid usage in steroid-dependent asthmatic patients: a meta-analysis

Methotrexate as an oral corticosteroid-sparing agent in severe asthma: the emergence of a responder asthma endotype

Background

Sustained use of oral corticosteroids is associated with significant side effects. It is therefore of interest to find a corticosteroid-sparing agent. In two meta-analyses, methotrexate resulted in a rather small reduction in the oral corticosteroid maintenance dose. We have used methotrexate as an oral corticosteroid-sparing agent in consecutive patients with severe bronchial asthma and find a need for a real-life observational study to evaluate the effect of methotrexate in clinical practice.

Methods

We analyzed the clinical data of 13 oral corticosteroid-dependent asthma patients with a mean prednisolone dose of 15 mg/day for up to 8 years. The diagnosis of asthma based on the clinical history, positive bronchodilator reversibility test, and variable airflow obstruction was secured by bronchial biopsies in all patients. We reviewed the literature and found 12 studies evaluating methotrexate as an oral corticosteroid-sparing agent in severe asthma and calculated the mean daily reduction in mg of prednisolone.

Results

Oral corticosteroids could be reduced in 8/13 patients, 61.5% (mean reduction 9.0 mg/day), and stopped in six of these patients. Five patients had no reduction and remained oral corticosteroid-dependent. Patients with the highest oral corticosteroid doses experienced the greatest reductions. Two patients stopped methotrexate due to side effects. FEV1 remained unaffected by methotrexate treatment and corticosteroid reduction.

Conclusions

Methotrexate has significant oral corticosteroid-sparing effect while maintaining an unaltered asthma control and spirometry. Methotrexate seems an effective oral corticosteroid-sparing agent in a significant proportion of patients with severe asthma. The specific asthma phenotype/endotype that responds needs further study.

New treatments for severe treatment-resistant asthma: targeting the right patient

Guidelines for asthma management focus on the use of combination inhaled treatment with corticosteroids and longacting β-agonists for symptomatic asthma. In more severe disease, other drugs such as leukotriene blockers and slow-release oral theophylline are added, with oral corticosteroids and anti-immunoglobulin E treatment with omalizumab for the most severe cases of asthma. Once-daily longacting β-agonists and inhaled corticosteroids are being developed. Longacting muscarinic antagonists might also provide additive benefit. New approaches are needed for the treatment of severe asthma, but patients need to be endotyped so that they can be directed for specific treatments. This Review focuses on the role of eosinophilic and neutrophilic inflammation, the attributes of chronic airflow obstruction, and the notion of corticosteroid insensitivity because potential targets for treatment have started to emerge from such analyses. How the best phenotypic or even better, the best endotypic responder with each new treatment, can be established will also be discussed. Newer treatments for asthma will emerge from better endotyping, leading to personalised medicine in asthma.

[Targeted therapies in severe asthma: the discovery of new molecules]

The pathophysiological mechanisms involved in the chronicity and phenotypic heterogeneity of asthma offer the prospect of new therapeutic opportunities. A better clinical and biological characterisation of selected patients has led to the development of targeted therapies. Studies are under way to demonstrate their efficacy and tolerance and also their impact on the natural history of the disease. This revue aims to examine the therapies, developed during the last ten years, that are based on the immunological mechanisms involved in the pathophysiology of asthma, essentially in its severe form. The rapid expansion of human monoclonal antibodies has allowed testing of various immunological pathways. Anti-IgE, anti- IL-5, and anti-IL-13 strategies seem the most promising. Antagonists to TNF-alpha and I'IL-4 have not succeeded in reducing the events related to severe asthma in a convincing manner. Molecules targeted against thymic stromal lymphopoietin (TSLP) and I'IL-9 are under development. These approaches are involved in the development of therapeutic programmes adapted to the patient's phenotype, that is to say a personalised approach to care.

Immunologic therapeutic interventions in asthma: impact on natural history

The discovery of new pathobiological pathways involved in asthma chronicity and reliefs offers novel therapeutic avenues. Enhanced phenotyping criteria associated with simple biologic characterization allowed to test targeted interventions in selected patients. Long-term studies are de facto lacking but required to address their impact on the natural history of the disease. Here, the authors review all potential available therapeutics based on immunologic pathways involved in asthma pathophysiology during the last decade.

Rationale for the use of immunomodulatory therapies in the Global Initiative for Asthma (GINA) step V asthma other than oral glucocorticosteroids

Asthma is a major problem worldwide, which is estimated to affect 300 million individuals. The global prevalence ranges from 1% to 18% of the population. The incidence, morbidity and mortality of the condition have increased over the last 50 years despite the development of new anti-asthmatic drugs. Fewer than 1% of the asthmatic population are steroid-dependent, but these patients consume most of the resources and time at asthma units. The consensus documents published by professional societies all support a stepwise therapeutic approach for asthma. However, patients who require frequent or continuous oral corticosteroid administration have received little attention. Due to the severe side-effects of oral corticosteroids when administered over long periods or at high doses, many drugs have been assessed in the search for a possible corticosteroid-sparing agent. Recently, the update of the Global Initiative for Asthma (GINA) introduced a new drug--omalizumab--as an alternative to oral corticosteroids in patients included in step V. Other alternatives include immunosuppressive drugs, among which methotrexate has been found to offer the best benefit/risk ratio. This paper will review, comment and criticize the evidence of the effectiveness of immunomodulatory drugs, as an alternative to oral glucocorticosteroid treatment in GINA step V asthma patients. The experience of the authors combined with the information of the literature will lead to the conclusion that methotrexate and omalizumab are the only advisable drugs and will clarify when and how these drugs should be used.

Recommendation for optimal management of severe refractory asthma

Patients whose asthma is not adequately controlled despite treatment with a combination of high dose inhaled corticosteroids and long-acting bronchodilators pose a major clinical challenge and an important health care problem. Patients with severe refractory disease often require regular oral corticosteroid use with an increased risk of steroid-related adverse events. Alternatively, immunomodulatory and biologic therapies may be considered, but they show wide variation in efficacy across studies thus limiting their generalizability. Managing asthma that is refractory to standard treatment requires a systematic approach to evaluate adherence, ensure a correct diagnosis, and identify coexisting disorders and trigger factors. In future, phenotyping of patients with severe refractory asthma will also become an important element of this systematic approach, because it could be of help in guiding and tailoring treatments. Here, we propose a pragmatic management approach in diagnosing and treating this challenging subset of asthmatic patients.

[Diagnosis and treatment guidelines for difficult-to-control asthma in children]

Children suffering from difficult-to-control asthma (DCA) require frequent appointments with their physician, complex treatment regimes and often admissions to hospital. Less than 5% of the asthmatic population suffer this condition. DCA must be correctly characterised to rule out false causes of DCA and requires making a differential diagnosis from pathologies that mimic asthma, comorbidity, environmental and psychological factors, and analysing the factors to determine poor treatment compliance. In true DCA cases, inflammation studies (exhaled nitric oxide, induced sputum, broncho-alveolar lavage and bronchial biopsy), pulmonary function and other clinical aspects can classify DCA into different phenotypes which could make therapeutic decision-making easier.

Managing patients with chronic severe asthma: rise to the challenge

Most asthmatic patients with moderate to severe disease can be satisfactorily managed with a combination of inhaled corticosteroids and beta(2)-agonists. However, there are perhaps 10% of the asthmatic population with persistent symptoms, impaired quality of life and excessive health-care utilization, despite this management regime. These patients often require frequent and even occasionally regular oral corticosteroid use. Chronic, severe asthma is a heterogeneous disease with distinct sub-phenotypes. A systematic diagnostic work-up may help to identify these distinct sub-phenotypes and this may help guide treatment and may even provide information about prognosis. Optimal treatment of chronic severe asthma should achieve the best possible asthma control and quality of life with the least dose of systemic corticosteroids. The choice and formulation of therapeutic agent is dictated by the severity of disease and includes conventional, immunosuppressive/immunomodulating and biologic therapies. Unfortunately, current asthma management guidelines offer little contribution to the care of the challenging patient with chronic severe asthma. This review article aims at summarizing the evidence regarding various therapeutic modalities for chronic severe asthma and also aims to provide a practical approach to diagnosis and management for the benefit of those who have a specific interest in this problematic condition.

Twelve years' experience with methotrexate for GINA treatment step 5 asthma patients

BACKGROUND

Certain studies have shown the beneficial effects of methotrexate (MTX) in asthma patients. Here we describe the drug's tolerance and oral corticosteroid sparing capacity in a long-term observational study.

METHODS

Forty-four patients with steroid-dependent asthma treated with 10 mg per week of oral MTX were prospectively followed for 91.3 +/- 39.5 months.

INTERVENTION

blood analysis each 3 months; spirometry monthly during the first 3 months and then every 3-6 months; liver ultrasound when an accumulated dose of 1500 mg was reached or whenever hepatic function was altered.

RESULTS

Two patients who dropped out early were excluded. Mean accumulated dose of MTX was 3.499 +/- 2.207 mg. Corticosteroid use was reduced from 15.1 +/- 8.2 to 2.64 +/- 5.35 mg (p < 0.008) and was withdrawn in 25 patients. In the remaining 17 patients, the dose was reduced from 17.1 +/- 9.1 mg to 6.5 +/- 6.8 mg. FEV(1) (% predicted) was 66.2 +/- 19.7 at the beginning and 65.7 +/- 19.1 at the end. Haematology was normal and only a mild increase in hepatic enzymes was observed in four patients, which normalized after treatment discontinuation. Hair loss was observed in one case.

CONCLUSIONS

In our series, a substantial, safe decrease in oral corticosteroid requirements was observed, probably due, to some extent, to MTX therapy. Oral corticosteroids were withdrawn completely in 59% of patients. Liver function was impaired in some patients; however, it recovered after MTX withdrawal and MTX could be safely reintroduced. The association of oral corticosteroids and MTX did not increase the number of side-effects and immunity was not affected. We were unable to identify a factor that could predict which patients would benefit most from MTX treatment. Some limitations of the study include the lack of control of asthma exacerbations and the lack of booster courses of corticosteroids.

Immunomodulatory and biologic therapies for severe refractory asthma

Despite undoubted efficacy of the combination of inhaled corticosteroids and beta(2)-agonists for most asthmatic patients with moderate-to-severe disease, there remains approximately 10% of the asthmatic population with serious unremitting symptoms, resulting in considerable impact on quality of life, disproportionate use of health care resources, and adverse effects from regular systemic steroid use. In an ideal world, optimal treatment of severe refractory asthma should achieve the best possible asthma control and quality of life with the least dose of systemic corticosteroids. The choice and formulation of therapeutic agent are dictated by the severity of disease and may include immunological modifiers and biologic therapies. Unfortunately, current asthma guidelines offer little contribution to the management of the challenging patient with severe refractory asthma and none of them have addressed therapeutic alternatives to oral corticosteroids. This article reviews the current evidence for immunomodulating and biologic approaches in severe refractory asthma.

An overview of chronic severe asthma

Most asthmatic patients with moderate to severe disease can be satisfactorily managed with a combination of inhaled corticosteroids and beta(2)-agonists. However, there are a few with persistent symptoms, impaired quality of life and excessive health-care utilization, despite this management regimen. These patients often require frequent and even occasionally regular oral corticosteroid use. Chronic, severe asthma is a heterogeneous disease and a systematic diagnostic work-up may help to guide treatment and may even provide information about prognosis. Optimal treatment of chronic severe asthma (CSA) should achieve the best possible asthma control and quality of life with the least dose of systemic corticosteroids. The choice and formulation of therapeutic agent is dictated by the severity of disease and includes conventional, immunosuppressive/immunomodulating and biologic therapies. Unfortunately, current asthma management guidelines offer little contribution to the care of the challenging patient with CSA. In this review, a diagnostic and therapeutic overview of CSA is provided for the benefit of those who have a specific interest in this problematic condition.

[Targeted immunologic therapies for severe asthma]

Better understanding of the cellular and molecular mechanisms of asthma have made it possible to envision a large number of new treatment targets. Clinical trials assessing some of these targets were recently published. The results of these trials were often disappointing. For example, parenteral administration of anti-interleukin-5 antibodies diminished bronchial eosinophilic inflammation but without improving either asthma symptoms or bronchial hyperreactivity. Other treatments are promising but have not yet been proved effective in patients with asthma: open studies with anti-TNF alpha antibodies are interesting but the efficacy of this treatment strategy remains uncertain and must be validated against placebo. The first targeted treatment approved for severe difficult-to-control allergic asthma is an anti-IgE monoclonal antibody (omalizumab).

The effects of a monoclonal antibody directed against tumor necrosis factor-alpha in asthma

RATIONALE

Neutralization of tumor necrosis factor-alpha (TNF-alpha) is an effective antiinflammatory therapy for several chronic inflammatory diseases.

METHODS AND OBJECTIVES

We undertook a double-blind, placebo-controlled, parallel-group design study in 38 patients with moderate asthma treated with inhaled corticosteroids but symptomatic during a run-in phase. Infliximab (5 mg/kg) or placebo was administered by intravenous infusion at Weeks 0, 2, and 6. We assessed clinical response by monitoring lung function, symptoms, and inhaled beta(2)-agonist usage using hand-held electronic devices.

RESULTS

The primary endpoint, change in morning PEF at Days 50-56 compared with the last 7 d of the run-in, was not significantly different on treatment. However, infliximab was associated with a decrease in mean diurnal variation of PEF at Week 8 (p = 0.02; 95% confidence interval [CI], -8.1 to -0.72). Furthermore, there was a decrease in the number of patients with exacerbations of asthma (p = 0.01; 95% CI, 4.4 to 52.7) and an increased probability of freedom from exacerbation with time (p = 0.03) in patients on infliximab (n = 14) compared with placebo (n = 18). In addition, infliximab decreased levels of TNF-alpha (p = 0.01) and other cytokines in sputum supernatants. There were no serious adverse events related to the study agent.

CONCLUSIONS

Treatment with infliximab was well tolerated and caused a decrease in the number of patients with exacerbations in symptomatic moderate asthma. The promising preliminary findings underscore the need to evaluate therapy directed against TNF-alpha in larger trials enrolling patients with more severe asthma.

Effects of topical application of methotrexate on nasal mucosa in rats: a preclinical assessment study

OBJECTIVE

The aim of this study is to investigate dose-dependent effect of the topical application of methotrexate (MTX) in rats on the normal nasal mucosa, liver tissue, liver enzymes, and hemoglobin levels.

STUDY DESIGN

Preclinical animal study.

SETTING

Twenty male adult wistar albino rats were randomly divided into 4 groups (n=5). A single puff of MTX (2.5 microg) was applied to both nasal cavities 2 times a day. The animals were given MTX 1 day a week in group 1, 3 days a week in group 2, and 5 days a week in group 3. Control group animals were given 1 puff of physiologic saline to both nasal cavities 5 days a week and 2 times a day. After 28 days, liver biopsies, blood samples, and 5 nasal mucosal biopsies were taken. Histological examination was made with respect to certain parameters semiquantitatively (grade 0-3). The aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels and hemoglobin counts were studied from blood samples.

RESULTS

There are no statistically significant differences with respect to histopathological parameters between the control group and the groups 1-3 (P>0.05). Histopathological examination of liver tissue did not reveal any evident difference between the control and study groups. Mean AST and ALT as liver function tests and hemoglobin counts were within normal limits. Topical application of MTX at these doses has no toxic effect on the nasal mucosa, the liver tissue, AST and ALT levels, and hemoglobin level.

CONCLUSIONS

These results have been encouraging to investigate use of the topical application of MTX in nasal manifestation of autoimmune disease or addition of the topical application of MTX to the steroid treatment in cases with massive nasal polyposis resistant to steroids and prone to recurrence.

Oral effects of low-dose methotrexate treatment

Methotrexate is used increasingly in low-dose regimes for a variety of conditions, particularly rheumatoid arthritis. While certain adverse effects of low-dose methotrexate have been described in detail, oral complications have received little attention. This article includes a summary of the uses and pharmacology of low-dose methotrexate and the mechanisms that lead to general and oral toxicity. The literature relevant to potential oral adverse effects is discussed and 7 illustrative cases are presented. The oral effects noted range from nonhealing ulcers to lymphoma-like lesions. Dental practitioners should be aware of the possible oral effects of low-dose methotrexate that have so far been largely unrecognized.

Methotrexate therapy of oral corticosteroid-dependent asthmatics reduces serum immunoglobulins: correlation with clinical response to therapy

BACKGROUND

Concomitant methotrexate (MTX) therapy of oral corticosteroid (CS)-dependent asthmatics has been shown to spare CS therapy, but the mechanism is unknown. In a previous report, we showed that MTX increases T cell inhibition by CS. In this report we focus on effects of MTX on immunoglobulin concentrations and their possible clinical relevance.

OBJECTIVE

To monitor changes in circulating leucocytes and Ig in a group of these patients during MTX therapy, and to relate these changes to clinical 'response' as defined by oral CS reduction.

METHODS

Sixteen severe asthmatics dependent on oral prednisolone 15 (7.5-25) mg/day in addition to high dose inhaled CS were treated with MTX 15 mg intramuscularly, weekly for 28 weeks. Prednisolone dosages were maintained constant for 12 weeks then reduced systematically over the next 16 weeks provided that asthma control did not deteriorate. Patients were classified a priori as 'responders' or 'non-responders' to MTX (reduction of initial oral prednisolone requirement by >or=50% or <50%, respectively). Patients were followed-up for a further 12 weeks after MTX withdrawal. Serum Ig and differential blood leucocyte counts were measured at baseline, 12, 28 and 40 weeks.

RESULTS

MTX therapy allowed significant, but individually variable, reductions in oral prednisolone dosages (P<0.00001) without alteration of lung function or symptoms. This was associated with significant reductions in mean serum concentrations of Ig of all classes, which reversed following MTX withdrawal. Reductions in IgE and IgG were significantly greater in the MTX 'responders' as compared with 'non-responders', and changes in IgE, IgG and IgM correlated with changes in prednisolone requirements. Differential blood leucocyte counts showed no significant variation.

CONCLUSION

MTX therapy reduced oral CS requirements in these severe asthmatics to a degree which correlated with reduced circulating Ig but not lymphopaenia, suggesting a possible cause and effect relationship. These reductions might also contribute to the documented incidence of opportunistic infection in these circumstances.

Benefits of low weekly doses of methotrexate in steroid-dependent asthmatic patients. A double-blind, randomized, placebo-controlled study

BACKGROUND

Though several drugs have been tested, the choice of the ideal steroid-sparing agent in steroid-dependent asthmatic patients remains unclear. Our objective was to evaluate the efficacy and tolerance of methotrexate in low weekly doses in order to decrease chronic oral steroid requirements in asthmatic patients.

METHODS

DESIGN

double blind randomized placebo-controlled study.

SETTING

The study was performed in a 760-bed teaching hospital.

PATIENTS

46 steroid-dependent asthmatic patients were randomized.

INTERVENTIONS

PATIENTS received 10mg of methotrexate or placebo once weekly for a year. The 6-methylprednisolone was progressively tapered (2mg/day every two weeks) until FEV1 diminished by 5% or more; 6-methylprednisolone was then increased until the previous FEV1 was reached, and the procedure was repeated throughout follow-up.

MEASUREMENTS

Blood and urine analyses and bone densitometry were performed at entry and at the end of the study. Pulmonary function was tested monthly during the first three months and then every three months until the end.

RESULTS

Thirty-nine patients were evaluated at interim analysis. A 54.8% decrease (9.5+/-4.9 mg/day) in 6-methylprednisolone dose was observed in the methotrexate group and a 4.4% decrease (0.5+/-7.2 mg/day) in the placebo group (P<0.001). There was no significant decrease of FEV1 in either group. No changes in bone metabolism were observed except for a non-statistically significant increase in osteocalcin levels in the treated group compared to a decrease in the placebo group. Toxicity was mild.

CONCLUSIONS

(1) Methotrexate is an effective steroid-sparing agent. (2) A dosage lower than the one recommended in the literature is effective. (3) Tolerance is good. (4) No benefit or detrimental effects in bone metabolism were observed after one year.

Asthma refractory to glucocorticoids: the role of newer immunosuppressants

Asthma is orchestrated by cytokine products of activated T cells. Glucocorticoids are thought to ameliorate asthma at least partly through T cell inhibition. Consequently, other T cell immunomodulatory agents have been assessed for asthma therapy. Since these agents may have serious unwanted effects, attention has been focused on patients with severe asthma refractory to maximal topical, and additional systemic glucocorticoid therapy. Although gold salts show a modest but significant glucocorticoid-sparing effect in severe asthma, lung function is not improved and not all patients respond. The minimum duration of a valid trial of therapy is probably 6 months. Unwanted effects include dermatitis, hepatic dysfunction, proteinuria and interstitial pneumonitis. Meta-analysis of trials of methotrexate in oral glucocorticoid-dependent asthma have confirmed that concomitant weekly methotrexate for a minimum of 3 to 6 months enables significant (approximately 20%) overall reduction in oral glucocorticoid requirements, although only approximately 60% of patients show a significant response. There is little effect on lung function. Blood count and liver function must be monitored. Opportunistic infection is rare but potentially fatal. Cyclosporine, administered for at least 3 months, is effective in only a proportion of patients with oral glucocorticoid-dependent asthma, where it may improve disease severity and/or enable oral glucocorticoid dosage reductions. Regular monitoring of renal function, blood pressure and blood concentrations of cyclosporine is required. The evidence that intravenous immunoglobulin (Ig) is of any benefit in patients with glucocorticoid-dependent asthma is at present equivocal. The therapy is expensive and associated with a high incidence of unwanted effects (fever, aseptic meningitis, urticaria). The macrolides tacrolimus (FK506) and sirolimus (rapamycin) have end effects similar to those of cyclosporine. Brequinar sodium, mycophenolate mofetil and leflunomide are inhibitors of de novo synthesis of pyrimidines and purines, to which T cells are particularly sensitive. Such drugs may in theory be beneficial for therapy of patients with oral glucocorticoid-dependent asthma. Humanized anti-CD4, anti-IgE and anti-interleukin (IL)-5 monoclonal antibodies, and other cytokine inhibitors such as soluble IL-4 receptor have entered early trials. The worth of current immunomodulatory drugs is limited since: (i) not all patients respond, and response cannot be predicted a priori; (ii) the high incidence of unwanted effects makes it difficult to assess overall benefit/risk ratios; (iii) there is increased risk of opportunistic infection and (theoretically) neoplasia; (iv) there are many relative and absolute contraindications to therapy; and (v) there is lack of knowledge about the long-term effects, beneficial or otherwise, of therapy.

The effect of the steroid-sparing response to low-dose methotrexate on bone metabolism in glucocorticoid-dependent asthmatics

BACKGROUND

The skeletal effects of low-dose methotrexate (MTX), in glucocorticoid-dependent asthmatics (GCDA), are unknown.

METHODS

We studied 9 patients from a total of 26 chronic GCDA who completed 28 weeks of MTX (15 mg weekly, intramuscularly). Prednisolone dose was not altered during the first 12 weeks, and was then reduced between 12 and 28 weeks. Mean (S.E.M.) age of the patients was 54 (4.0) years. They had normal bone mineral density (BMD), were not taking medication that affected bone metabolism (except prednisolone and inhaled corticosteroids) and all achieved at least 50% reduction in prednisolone dose at 28 weeks. Blood and urine samples were obtained at baseline, 12, 28 and 40 weeks for measurement of serum osteocalcin (OC) and bone alkaline phosphatase (Bone-ALP) as formation markers and urinary deoxypyridinoline (DPD) and N-terminal cross-linked telopeptide of type I collagen (NTX-I) as resorption markers.

RESULTS

Concurrently with the changes in prednisolone dosage serum OC levels increased significantly at 28 weeks (p<0.008) (8.1+/-1.0 ng/ml) compared to baseline (4.7+/-0.6 ng/ml) and 12 weeks (5.1+/-0.6 ng/ml), but trended back by 40 weeks (6.6+/-0.6 ng/ml). No significant changes were observed for the other bone markers between baseline and the other time points.

CONCLUSIONS

The beneficial effects of steroid reduction on bone metabolism do not appear to be impaired by concomitant MTX treatment at least over 12 weeks.

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.

Low-dose methotrexate for advanced pulmonary disease in patients with cystic fibrosis

Inflammation is a hallmark in the pathogenesis of pulmonary destruction in cystic fibrosis (CF). There is no proven effective systemic anti-inflammatory treatment for CF patients with advanced pulmonary disease. Methotrexate (MTX) is known as an effective anti-inflammatory treatment in asthma and in juvenile rheumatoid arthritis. The question was: Is an improvement in pulmonary function achievable with low-dose MTX in patients with cystic fibrosis and advanced pulmonary disease.?

METHODS

We treated five CF patients with advanced pulmonary disease, who deteriorated in spite of intensive conventional therapy on an individual basis with low-dose MTX. FEV1% and immunoglobulin G (IgG) serum levels were followed from the year before to the year after starting with MTX.

RESULTS

In the year before starting with MTX, FEV1% decreased (median: 10% FEV1; range 9-15% FEV1; P<0.005) after starting with MTX, FEV1% increased (median: 9% FEV1; range: 2-15% FEV1; P<0.05). IgG changed (median: -2 g/l; range: 0.2 to -7.3 g/l) in the first year with MTX.

CONCLUSION

These preliminary data suggest a beneficial effect of MTX even in advanced pulmonary disease in CF patients and supports the need for a controlled prospective study.

Low dose methotrexate in inflammatory bowel disease: current status and future directions

Despite many recent advances, some notable limitations exist in the medical management of patients with inflammatory bowel disease. Glucocorticoids suppress active inflammation very effectively, but their long term use is associated with high rates of relapse and unacceptable toxicity. 6-Mercaptopurine and its prodrug azathioprine are effective in inducing and maintaining remission; however, a significant number of patients are resistant or intolerant to thiopurines. Low dose methotrexate, an anti-inflammatory drug, is a well established medication for rheumatoid arthritis and psoriasis. After an initial report in 1989, several clinical trials and analyses of clinical notes have examined the role of methotrexate in patients with ulcerative colitis and Crohn's disease. This review was conducted to summarize the current knowledge about the underlying basic anti-inflammatory mechanisms of methotrexate as well as the pharmacology and toxicology of this drug with particular emphasis on inflammatory bowel disease. It also critically evaluates all existing trials not only in the induction of remission but also in maintenance therapy. We conclude that low dose methotrexate is an effective and safe treatment in glucocorticoid-dependent and thiopurine intolerant patients with Crohn's disease but not ulcerative colitis. It remains to be seen whether low dose methotrexate may also be useful in long term maintenance therapy in patients with inflammatory bowel disease.

Refractory asthma

Treating patients with refractory asthma remains an ongoing challenge. Although most patients respond to large doses of systemic corticosteroid, the adverse effects associated with such a treatment limit its general use. Clinicians treating patients with refractory asthma must consider tapering systemic corticosteroid at every opportunity. Recent advances in the understanding of the pathogenesis of refractory asthma and corticosteroid resistance have fueled further study in the mechanisms of these processes and have prompted consideration of new treatment approaches. Unfortunately, most alternative approaches require more rigorous evidence to support their regular use.

Children with difficult asthma: a practical approach

Many open studies investigating the effects of innovative treatments for steroid-dependent asthma demonstrate some benefit. This is also true of the majority of placebo arms in placebo-controlled trials. This suggests that children with difficult asthma benefit from the high level of input that is typically provided in clinical trials, with or without additional medication. Such intensive management of patients, with the emphasis on establishing the diagnosis, improving adherence, and identifying provoking factors, is the key to optimizing asthma control for these children. For patients with genuinely severe asthma, despite high doses of conventional treatment, a greater understanding of the pathological basis of persistent symptoms is needed. Identification of different pathological subtypes of severe asthma should allow for more rational prescribing of asthma therapy, as well as the design of further trials of potential steroid-sparing treatments.

Novel drugs for treating asthma

The health burden of asthma is increasing globally at an alarming rate, providing a strong impetus for the development of new therapeutics, particularly drugs that may prevent development of the disease. Currently available inhaled bronchodilators and anti-inflammatory drugs are effective in most asthmatic patients, but this palliative therapy requires long-term daily administration. Despite considerable efforts by the pharmaceutical industry, it has been difficult to develop novel therapeutic agents, the leukotriene antagonists being the only new class of asthma treatments to be licensed in the past 30 years. It is clearly important to understand more about the underlying mechanisms of asthma and about how currently used drugs work before rational improvements in therapy can be expected. There are numerous therapies in clinical development that combat the inflammation found in asthma, specifically targeting eosinophils, IgE, adhesion molecules, cytokines (interleukin-4, -5, -13) and chemokines, inflammatory mediators, and cell signaling (kinase inhibitors). In particular, there is the obvious need for new therapy for severe asthma that is poorly controlled by high-dose corticosteroids as well as agents to counter acute emergency asthma. A long-term goal is to develop disease-modifying immunotherapy that could be introduced in childhood to alter the natural history of asthma. Thanks to the extensive efforts of the pharmaceutical industry, we can expect the introduction of a range of novel therapies for asthma in the near future.

New medications for asthma

The therapy for chronic stable asthma and acute asthma exacerbations continues to evolve as the pathogenesis of asthma becomes better understood. Although the role of many standard therapies for asthma is well established, some carry significant side effects. The newer anti-inflammatory medications have demonstrated both therapeutic benefit as well as reassuring safety profiles. The challenge of the future is to incorporate the newer medications described, as well as those still being examined, into a treatment regimen that can deliver maximal therapeutic benefit with the lowest possible incidence of side effects.

Asthma--the changing face of drug therapy

Until the recent introduction of long acting beta 2-agonists and the leukotriene antagonists, the drug treatment of asthma had remained largely unchanged for a quarter century. Recent studies have demonstrated the efficacy of the long acting beta 2-agonists in the management of asthma in children and highlighted their value as an adjunct to inhaled corticosteroids. The leukotriene antagonists are an important new class of drug therapy which target a specific area of asthma pathogenesis. Whilst they have been shown to be effective for asthma, their exact role in the clinical situation remains to be established. Recent guidelines have emphasised the important role of inflammation in persistent asthma and recommended the early institution of anti-inflammatory treatment. Many patients remain uncontrolled despite high doses of anti-inflammatory agents including oral corticosteroids. Recent experience with other immunomodulatory agents such as cyclosporin, methotrexate and intravenous immunoglobulin has highlighed their potential as steroid sparing agents. With improved understanding of asthma pathogenesis the potential for specific targeted therapies has become evident. Monoclonal antibodies to IgE and certain cytokines are being investigated as possible treatments for asthma. Similarly, preliminary studies of selective phosphodiesterase inhibitors in asthmatic individuals have been encouraging. Other potential therapies include platelet-activating factor receptor antagonists, tryptase inhibitors and prostaglandin E analogs. The continued development of such targeted treatments should ensure a greater diversity of therapeutic options for the management of asthma in the new millennium.

Methotrexate as a steroid sparing agent for asthma in adults

BACKGROUND

Sustained oral corticosteroid use can lead to complications, so there is interest in identifying agents that can reduce oral steroid use in people with asthma. Methotrexate has attracted attention as a possible steroid sparing agent in patients with chronic oral steroid dependent asthma.

OBJECTIVES

The objective of this review was to assess the effects of adding methotrexate to oral corticosteroids in adults with stable asthma who are dependent on oral corticosteroids.

SEARCH STRATEGY

The Cochrane Airways Group trials register and reference lists of identified articles were searched.

SELECTION CRITERIA

Randomised trials of the addition of methotrexate compared with placebo in adult steroid dependent asthmatics. Duration of therapy needed to be at least 12 weeks.

DATA COLLECTION AND ANALYSIS

Trial quality was assessed and data extraction was carried out by two reviewers independently. Study authors were contacted for missing information.

MAIN RESULTS

Ten trials involving a total of 185 people were included. Study design and quality, corticosteroid dosages and outcomes varied widely. There was a reduction in oral corticosteroid dose favouring methotrexate in parallel trials (weighted mean difference -4.1 mg per day, 95% confidence interval -6.8 to -1.3) and also in cross-over trials (weighted mean difference -2.9 mg per day, 95% confidence interval -5.9 to -0.2). There was no difference between methotrexate and placebo for forced expiratory volume in one minute (weighted mean difference 0.12 litre, 95% confidence interval -0.21 to 0.45). Hepatotoxicity was a common adverse effect with methotrexate compared to placebo (odds ratio 6.9, 95% confidence interval 3.1 to 15.5).

REVIEWER'S CONCLUSIONS

Methotrexate may have a small steroid sparing effect in adults with asthma who are dependent on oral corticosteroids. However, the overall reduction in daily steroid use is probably not large enough to reduce steroid-induced adverse effects. This small potential to reduce the impact of steroid side-effects is probably insufficient to offset the adverse effects of methotrexate.

Novel therapy for asthma

The health burden of asthma is increasing globally at an alarming rate, providing a strong impetus for the development of new therapeutics. Currently available inhaled bronchodilators and anti-inflammatory drugs are effective in most asthmatics, but this palliative therapy requires long-term daily administration. Despite considerable efforts by the pharmaceutical industry, it has been difficult to develop novel therapeutic agents; the leukotriene antagonists and synthesis inhibitors being the only new class of asthma treatments to have been licensed in the last 30 years. It is clearly important to understand more about the underlying mechanisms of asthma and about how current drugs work before rational improvements in therapy can be expected. There are numerous therapies in clinical development that combat the inflammation found in asthma, specifically targeting eosinophils, IgE, adhesion molecules, cytokines and chemokines, inflammatory mediators and cell signalling. In particular, there is the obvious need for new therapy for severe asthma that is poorly controlled by high doses of corticosteroids, as well as agents to counter acute emergency asthma. A long-term goal is to develop disease-modifying immunotherapy, that could be introduced in childhood to alter the natural history of asthma. Thanks to the extensive efforts of the pharmaceutical industry, in the near future we can expect the introduction of a range of novel therapies for asthma.

Management of steroid-dependent asthma with methotrexate: a meta-analysis of randomized clinical trials

Our objective was to determine whether methotrexate is an effective steroid-sparing agent for patients with severe asthma. Published reports of controlled trials assessing the use of methotrexate in asthma were identified by a search of the MEDLINE, EMBASE, CINAHL, Biological Abstracts on CD, and Current Contents databases. Bibliographies from identified studies and from review articles were manually searched. Published and unpublished reports in any language were identified and assessed for inclusion in the meta-analysis. We selected randomized, double-blind, placebo-controlled trials in which low-dose methotrexate was administered to corticosteroid-dependent asthmatics, and oral steroids were subsequently tapered according to the patients' clinical status. Data were extracted independently by two reviewers. For all eligible trials, the mean reduction in oral corticosteroid dose, the mean change in FEV1, and the standard deviations, were calculated for the treatment and control groups. Data concerning side-effects of therapy were also extracted. Data from 12 studies, reporting on a total of 250 patients, were pooled using a weighted average method, with weights proportional to the inverse of the variance of the treatment effect. Compared to placebo, the use of methotrexate was associated with a pooled 6.0% improvement in FEV1 (95% CI, 1.0-11%) and an 18.2% reduction in oral steroid use (95% CI, 11.7-24.7%). This corresponded to a 3.3 mg day-1 greater reduction in oral steroid use for patients taking methotrexate than for those taking placebo (95% CI, 2.1-4.4 mg day-1). Gastrointestinal complications and transient increases in liver enzymes were more common in patients randomized to methotrexate. Three potentially life-threatening side-effects (two pneumonias and one liver dysfunction) occurred in 159 patients randomized to methotrexate vs. none in those patients on placebo. It was concluded that methotrexate allowed a modest reduction in oral corticosteroid compared to patients receiving placebo. The benefit is relatively small, however, and should be balanced against the potential for side-effects associated with the use of methotrexate.

Methotrexate inhibition of inducible nitric oxide synthase in murine lung epithelial cells in vitro

Nitric oxide (NO) is produced in lung epithelial cells by nitric oxide synthases (NOSs), which can enhance inflammation and edema formation. The inducible NOS (iNOS, type II NOS) has been shown to be increased in lung disorders such as asthma. Therapy for asthma includes antiinflammatory agents such as corticosteroids and antineoplastic agents such as methotrexate (MTX). We hypothesized that NO production by epithelial cells in vitro would be attenuated by MTX, and that this effect would be additive with corticosteroids. In order to test this hypothesis, cells from the murine lung epithelial-cell line LA-4 were cultured to confluence and stimulated to express iNOS and produce NO by cytomix, a combination of human tumor necrosis factor-alpha (TNF-alpha), human interleukin-1beta (IL-1beta) and murine interferon-gamma (IFN-gamma). Nitrite and nitrite + nitrate were measured in the culture supernatant fluids as an index of NO production. MTX caused a dose- and time-dependent inhibition of nitrite and nitrite + nitrate (P < 0.05, all comparisons). Importantly, the inhibition of NO production by MTX (10(-3) M) was additive with dexamethasone (10(-5) to 10(-9) M), but cyclophosphamide, bleomycin, and cytosine-beta-D-arabinofuranoside (Ara-C), other antineoplastic agents, caused no inhibition of NO production. To investigate the mechanism of NO inhibition with MTX, we added tetrahydrobiopterin, which reversed the inhibition. MTX had no effect on the expression of iNOS on Western blotting or iNOS mRNA on Northern blotting. These data show that MTX inhibits NO production by iNOS in murine lung epithelial cells in vitro and that MTX produces added inhibition with corticosteroids, and suggest a potential strategy for reducing NO production in vivo.