The efficacy and safety of salmeterol compared to theophylline: meta-analysis of nine controlled studies

Evaluation and Management of Difficult-to-Treat and Severe Asthma: An Expert Opinion From the Korean Academy of Asthma, Allergy and Clinical Immunology, the Working Group on Severe Asthma

Severe asthma (SA) presents in about 3%-5% of adult asthmatics and is responsible for over 60% of asthma-related medical expenses, posing a heavy socioeconomic burden. However, to date, a precise definition of or clear diagnostic criteria for SA have not been established, and therefore, it has been challenging for clinicians to diagnose and treat this disease. Currently, novel biologics targeting several molecules, such as immunoglobulin E, interleukin (IL)5, and IL4/IL13, have emerged, and many new drugs are under development. These have brought a paradigm shift in understanding the mechanism of SA and have also provided new treatment options. However, we need to agree on a precise definition of and its diagnostic criteria for SA. Additionally, it is necessary to explain the diagnostic criteria and to summarize current standard and additional treatment options. This review is an experts' opinion on SA from the Korean Academy of Asthma, Allergy, and Clinical Immunology, the Working Group on Severe Asthma, and aims to provide a definition of and diagnostic criteria for SA, and propose future direction for SA diagnosis and management in Korea.

Salmeterol Xinafoate

Salmeterol xinafoate is a potent and a long-acting β2-adrenoceptor agonist. It is prescribed for the treatment of severe persistent asthma and chronic obstructive pulmonary disease. Different methods were used to prepare (R)-(-)-salmeterol such as: mixing a sample of 4-benzyloxy-3-hydroxymethyl-ω-bromoacetophenone with sodium lauryl sulfate and the mixture was added to the microbial culture of Rhodotorula rubra, treatment of p-hydroxyacetophenone with Eschenmoser's salt and carbonate exchange resin followed by a sequence of supported reagents and scavenging agents or via Rh-catalyzed asymmetric transfer hydrogenation. The enantioselective synthesis of (S)-salmeterol was achieved via asymmetric reduction of the azidoketone 4 by Pichia angusta yeast. Physical characteristics of salmeterol xinafoate were confirmed via: X-ray powder diffraction pattern, thermal analysis and UV, vibrational, nuclear magnetic resonance, and mass spectroscopical data. Initial improvement in asthma control may occur within 30 min following oral inhalation of salmeterol in fixed combination with fluticasone propionate. Clinically important improvements are maintained for up to 12 h in most patients. It is extensively metabolized in the liver by hydroxylation, thus increased plasma concentrations may occur in patients with hepatic impairment.

Progress in the management of childhood asthma

Asthma has become the most common chronic disease in childhood. Significant advances in epidemiological research as well as in therapy of pediatric asthma have been made over the past 2 decades. In this review, we look at certain aspects therapy of childhood asthma, both in the past and present. Literature review on allergen avoidance (including mites, cockroach and cat), intensive therapy with β(2)-agonists in acute asthma (administering via continuous nebulization and intravenous routes), a revisit of theophylline use and its action, the use of inhaled corticosteroids in various phases of childhood asthma and sublingual immunotherapy in asthma are examined. Recent facts and dilemmas of these treatments are identified along with expression of our opinions, particularly on points of childhood asthma in the Asia-Pacific, are made in this review.

Asthma management and asthma control in São Paulo, Brazil and Uppsala, Sweden: a questionnaire-based comparison

BACKGROUND AND AIMS

The Global Initiative Against Asthma (GINA) was developed to meet the global challenge of asthma. GINA has been adopted in most countries and comparison of asthma management in different parts of the world may be of help when assessing the global dissemination of the guideline. The overall goals in GINA include that asthma patients should be free of symptoms, acute asthma attacks and activity limitations. The aim of the present study was to compare asthma management and asthma control in São Paulo, Brazil and Uppsala, Sweden.

MATERIALS AND METHODS

Information was collected from asthmatics in São Paulo and Uppsala with a questionnaire. The questionnaire dealt with the following issues: symptoms, smoking, self-management, hospital visits, effect on school/work and medication.

RESULTS

The São Paulo patients were more likely to have uncontrolled asthma (36% vs 13%, P < 0.001), having made emergency room visits (57% vs 29%, P < 0.001) and having lost days at school or work because of their asthma (46% vs 28%, P = 0.03) than the asthmatics from Uppsala. There were no difference in the use of inhaled corticosteroids, but the Brazilian patients were more likely to be using theophylline (18% vs 1%, P = 0.001) and less likely to be using long-acting beta-2 agonists (18% vs 37%, P < 0.001).

CONCLUSION

We conclude that the level of asthma control was lower among the patients from São Paulo than Uppsala. Few of the patients in either city reached the goals set up by GINA. Improved asthma management may therefore lead to health-economic benefits in both locations.

Effects of asthma treatment: the present and future

The increasing burden of asthma in both primary and secondary care has led to extensive research into its genetics, pathophysiology and treatment over the past few decades. Inhaled corticosteroids remain an integral component in all but the mildest disease, although despite a low-to-moderate dose, many individuals remain symptomatic. In patients with persistent symptoms despite inhaled corticosteroids, a variety of different nonsteroidal second-line therapies are available as add-on therapy. In this review, existing and potential future pharmacological strategies involved in the management of asthma will be highlighted.

Comparison of salmeterol/fluticasone propionate (FP) combination with FP+sustained release theophylline in moderate asthma patients

OBJECTIVES

To compare the efficacy and safety of the salmeterol/fluticasone propionate combination product with concurrent sustained release theophylline plus fluticasone propionate in adult Japanese patients with persistent asthma.

DESIGN

Multicentre, randomised, double-blind, double-dummy, parallel-group study.

PATIENTS AND INTERVENTIONS

Three hundred and eighty-three asthmatic patients receiving sustained release theophylline 200-400mg/day entered the study and were randomised to receive either salmeterol/fluticasone propionate combination (SFC) 50microg/250microg+1 placebo tablet, fluticasone propionate 250microg+1 sustained release theophylline 200mg (SR-T+FP), twice daily for 8 weeks.

RESULTS

The adjusted mean change morning peak expiratory flow (PEF) over 8 weeks was 29.8L/min in the SFC group and 16.3L/min in the SR-T+FP group, with a treatment difference of 13.4L/min (p=0.0004). SFC improved evening PEF, FEV1, V50 and V25 at the completion of treatment to a greater extent than SR-T+FP (all p<0.05). A higher percentage of patients on SFC were symptom free (p=0.0286) and rescue free (ns) than those on SR-T+FP. There was not a statistically significant difference between treatments in symptom scores. Both treatments were well tolerated.

CONCLUSIONS

The finding that SFC was associated with greater improvements in lung function than SR-T+FP, a commonly employed treatment for asthmatic patients in Japan, suggests that SFC should be the preferred therapeutic option in these patients.

[Evaluation of pulmonary function in the elderly. Intergroupe Pneumo Gériatrie SPLF-SFGG]

Aging is associated with a progressive decrease in lung function. As a consequence of aging, individual's reserve is diminished, but this decrease is heterogeneous between individual subjects. Many factors are involved in the overall decline in lung function. The prevalence of asthma in the elderly is estimated between 6 and 10%. Mortality due to COPD is increasing, especially among older subjects. Older subjects are at an increased risk of developing chronic diseases such as Parkinson's disease, which can have consequences for lung function. Under-nutrition is also common in the elderly and can produce sarcopenia and skeletal muscle dysfunction. The presentation of respiratory disorders may differ in the elderly, especially because of a lack of perception of symptoms such as dyspnea. The impact of bronchodilatators or corticosteroids on respiratory function has not been studied in the elderly. Drugs usually used for the treatment of hypertension or arrhythmias, which are often observed with aging, can have pulmonary toxicity. There is no difference between functional evaluation in younger and older subjects but it is more difficult to find predicted values for older patients. Performing pulmonary function tests in older patients is often difficult because of a higher prevalence of cognitive impairment and/or poor coordination. When assessing pulmonary function in the elderly, the choice of tests will be depend on the circumstances, with the use of voluntary manoeuvres dependent on the condition of the patient.

Comparison of the efficacy of salmeterol/fluticasone propionate combination in Japanese and Caucasian asthmatics

INTRODUCTION

The effect of ethnicity on the efficacy of salmeterol (S)+fluticasone propionate (FP) has not been examined in Japanese and Caucasian asthmatics. In this study, the efficacy of combination treatment with S and FP from a single inhaler (SFC) was compared with concurrent treatment with S and FP administration from separate inhalers (S+FP) in Japanese and Caucasian asthmatics.

METHODS

This was a randomised, double-blind, crossover study in male and female Japanese (n=18) and Caucasian (n=17) asthmatics (50-100% predicted FEV(1); >35% reversibility in sGaw). Subjects received SFC (S 50 mcg/FP 250 mcg b.i.d.) and S+FP (S 50 mcg b.i.d.+FP 250 mcg b.i.d.) for 14 days. sGaw and FEV(1) were determined 0-12h after the first and last doses.

RESULTS

Treatment with both SFC and S+FP produced marked bronchodilation, which was maintained 0-12h after the first dose. Baseline sGaw and FEV(1) increased up to 51% and 180 mL, respectively, in Japanese subjects over 2 weeks of treatment, with similar improvements in Caucasian subjects. On Day 14 the 0-12h S+FP:SFC treatment ratios (90% CI) for sGaw AUC and peak were 1.05 (0.98, 1.12) and 1.05 (0.97, 1.14), respectively, in Japanese subjects, and 0.99 (0.92, 1.07) and 0.98 (0.89, 1.07), respectively, in Caucasian subjects, with no difference between the two ethnic groups.

CONCLUSIONS

The finding of a similar significant bronchodilator response in Japanese and Caucasian asthmatics following concurrent and combination treatment with salmeterol and FP suggests that the therapeutic response to these agents is comparable and independent of ethnicity in Japanese and Caucasian asthma patients.

Long-acting beta2-agonists versus theophylline for maintenance treatment of asthma

BACKGROUND

Theophylline and long acting beta-2 agonists are bronchodilators used for the management of persistent asthma symptoms, especially nocturnal asthma. They represent different classes of drug with differing side-effect profiles.

OBJECTIVES

To assess the comparative efficacy, safety and side-effects of long-acting beta-2 agonists and theophylline in the maintenance treatment of adults and adolescents with asthma.

SEARCH STRATEGY

We searched the Cochrane Airways Group trials register and reference lists of articles. We also contacted authors of identified RCTs for other relevant published and unpublished studies and pharmaceutical manufacturers. Most recent search: November 2006.

SELECTION CRITERIA

All included studies were RCTs involving adults and children with clinical evidence of asthma. These studies must have compared oral sustained release and/or dose adjusted theophylline with an inhaled long-acting beta-2 agonist.

DATA COLLECTION AND ANALYSIS

In original review, two reviewers independently assessed trial quality and extracted data, similarly in this update two reviewers undertook this. Study authors were contacted for additional information.

MAIN RESULTS

Thirteen studies with a total of 1344 participants met the inclusion criteria of the review. They were of varying quality. There was no significant difference between salmeterol and theophylline in FEV(1) predicted (6.5%; 95% CI -0.84 to 13.83). However, salmeterol treatment led to significantly better morning PEF (mean difference 16.71 L/min, 95% CI 8.91 to 24.51) and evening PEF (mean difference 15.58 L/min, 95% CI 8.33 to 22.83). Salmeterol also reduced the use of rescue medication. Formoterol, used in two studies was reported to be as effective as theophylline. Bitolterol, used in only one study, was reported to be less effective than theophylline. Participants taking salmeterol experienced fewer adverse events than those using theophylline (Parallel studies: Relative Risk 0.44; 95% CI 0.30 to 0.63, Risk Difference -0.11; 95% CI -0.16 to -0.07, Numbers Needed to Treat (NNT) 9; 95% CI 6 to 14). Significant reductions were reported for central nervous system adverse events (Relative Risk 0.50; 95% CI 0.29 to 0.86, Risk Difference -0.07; 95% CI -0.12 to -0.02, NNT 14; 95% CI 8 to 50) and gastrointestinal adverse events (Relative Risk 0.30; 95% CI 0.17 to 0.55, Risk Difference -0.11; 95% CI -0.16 to -0.06, NNT 9; 95% CI 6 to 16).

AUTHORS' CONCLUSIONS

Long-acting beta-2 agonists, particularly salmeterol, are more effective than theophylline in improving morning and evening PEF, but are not significantly different in their effect on FEV1. There is evidence of decreased daytime and nighttime short-acting beta-2 agonist requirement with salmeterol. Fewer adverse events occurred in participants using long-acting beta-2 agonists (salmeterol and formoterol) as compared to theophylline.

Summing up 100 years of asthma

In this review, we aim to lead the readers through the historical highlights of pathophysiological concepts and treatment of asthma. Understanding the nature and links of asthma has modeled our diagnostic, pathophysiological and therapeutic thinking and acting. The recognition of its heterogeneous nature in combination with several refined and sophisticated technologies will mark a new era of phenotype-specific approach and treatment of asthma.

Uncontrolled asthma: a review of the prevalence, disease burden and options for treatment

An estimated 300 million people are affected by asthma worldwide and the burden is likely to rise substantially in the next few decades. Estimates of the prevalence of asthma range from 7% in France and Germany to 11% in the USA and 15-18% in the United Kingdom. Approximately 20% of these patients have severe asthma, of which 20% is inadequately controlled. Patients with inadequately controlled severe persistent asthma are at a particularly high risk of exacerbations, hospitalization and death, and often have severely impaired quality of life. Current management of asthma focuses on a stepwise approach tailored to disease severity. In addition to needing high-dose inhaled corticosteroids (ICS) and long-acting beta(2)-agonists (LABAs), patients with severe persistent asthma often require additional controller medications, such as anti-leukotrienes, oral LABAs, oral corticosteroids and/or anti-IgE therapy. There is currently little evidence on which to base treatment decisions in patients with inadequately controlled severe persistent asthma already treated with ICS and LABAs. The anti-IgE monoclonal antibody omalizumab is the most recent addition to the list of treatment options for these patients and has been shown to reduce exacerbations and emergency visits and improve lung function, symptom scores and quality of life in patients with difficult-to-treat asthma whose symptoms remain inadequately controlled despite receiving ICS and LABAs. Comparative trials are needed to determine the merits of different treatments and strategies for patients with inadequately controlled severe persistent asthma and to identify patients likely to benefit from new treatment options.

Positioning of glucocorticosteroids in asthma and allergic rhinitis guidelines (versus other therapies)

Asthma and allergic rhinitis are both characterized by airway inflammation, and glucocorticosteroids form the cornerstone of their pharmacologic treatment. All patients with asthma should be prescribed rapid-acting inhaled beta2-agonists as needed to use as rescue therapy in case of symptoms. As soon as patients experience symptoms at least once a week, controller medications should be started on a daily basis to achieve and maintain control of their asthma. Intranasal corticosteroids are given as first-line therapy for moderate to severe persistent rhinitis. Depending on the dominant symptom, H1-antihistamines, decongestants, or ipratropium can be added after re-evaluation.

Combination therapy of long-acting beta agonists and inhaled corticosteroids in the management of chronic asthma

Both the Global Initiative for Asthma (GINA) and the National Heart, Lung and Blood Institute (NHLBI) Expert Panel guidelines recommend combination treatment with inhaled corticosteroids (ICSs) and inhaled long-acting beta-agonists (LABAs) for patients whose asthma is not adequately controlled by low doses of ICSs alone. Not only is this combination more effective than the combination of either theophylline or leukotriene modifiers with ICSs, there is suggestive evidence that the results with LABAs and ICSs may be more than additive. Through the effect of each one on the receptor for the other, they may have a synergistic action. This marked effectiveness of the combination, particularly when combined in the same device, has led to new objectives and novel applications. Therefore, for the first time, it appears that the Goals of Asthma Therapy, as outlined in the guidelines, are achievable for many patients with asthma. Also, at least for combination therapies including formoterol, adjustable dosing and perhaps even use as a rescue as well as a maintenance therapy may be possible.

Combination therapy of long-acting beta2-adrenoceptor agonists and corticosteroids for asthma

Twice-daily combination therapy of inhaled corticosteroids and long-acting beta2-adrenoceptor agonists (LABA) is now established as a most effective treatment for moderate to severe asthma and is available in a combined single inhaler. The benefits of combination therapy include better day-to-day control and a reduction in exacerbations compared with monotherapy with inhaled corticosteroids at a lower dose. Total control of asthma, defined as no daytime or night-time symptoms, no use of rescue beta2-adrenoceptor agonists (beta2-agonists), no exacerbations and a peak flow rate of >80% predicted, may be achieved with the use of combined salmeterol/fluticasone in up to 41% of patients with moderate to severe asthma, compared with only 28% of patients treated with fluticasone alone. Adjustable maintenance dosing with budesonide/formoterol may provide better control when compared with fixed-dosing combination regimens. Other therapies combining effectively with inhaled corticosteroids include slow-release theophylline and leukotriene inhibitors, montelukast and zafirlukast, but LABA are the most efficacious. Molecular interactions between corticosteroids and beta2-adrenoceptors may underlie the clinical added benefits of combination therapy. Corticosteroids may increase the number of beta2-adrenoceptors and their coupling with Gs proteins, while beta2-agonists may induce glucocorticoid receptor nuclear translocation, activate transcription factor/enhancer binding protein C/EBPalpha together with corticosteroids, or phosphorylate corticosteroid receptors. The combination of corticosteroids and LABA potentiates inhibition of interleukin-8 and eotaxin release from human airway smooth muscle cells and granulocyte-macrophage colony-stimulating factor release from epithelial cells, and also the inhibition of airway smooth muscle cell proliferation. It is important to determine whether there is a potentiating effect of combination therapy compared with corticosteroid treatment alone on airway inflammation and airway wall remodelling. Improvements in combination therapy include a once-daily preparation and possible combination of inhaled corticosteroids with newer drugs such as phosphodiesterase IV inhibitors.

Effects of dual therapy with corticosteroids plus long acting beta2-agonists in asthma

Asthma is a common condition characterised by inflammation, airway hyperresponsiveness and reversible airflow obstruction. Effective pharmacotherapy must therefore be aimed at attenuating these underlying hallmark features. Despite the use of regular low-to-moderate doses of inhaled corticosteroids, many patients remain symptomatic and require further 2nd line controller therapy. The addition of a concomitant long acting beta2-agonist provides an effective means in which to alleviate symptoms and reduce exacerbation frequency. Moreover, both agents can be combined in a single inhaler, and provide patients with a more convenient and effective way in which to deliver treatment to the endobronchial tree. This evidenced-based review article discusses the effects of such combination inhalers upon a variety of outcome parameters and their effects upon asthmatics across a range of severities.

Long-acting beta2-agonists or leukotriene receptor antagonists as add-on therapy to inhaled corticosteroids for the treatment of persistent asthma

It is well accepted that the combination of inhaled corticosteroids (ICSs) and long-acting beta2-agonists (LABAs) is effective in achieving asthma control, as it treats both components of asthma pathophysiology, namely inflammation and smooth muscle dysfunction of the airways. Leukotriene receptor antagonists (LTRAs) can also be used as add-ons to ICS therapy in patients whose asthma is not controlled by ICSs alone. The purpose of this review is to compare the effectiveness of ICSs plus LABAs with that of ICSs plus LTRAs for the treatment of persistent asthma that is not controlled by ICSs alone. Several studies have shown that, in comparison with an ICS plus an LTRA, the addition of an LABA to ICS therapy provides greater improvements in pulmonary function and overall control of asthma as measured by use of rescue medication and the number of exacerbations of the asthma, symptom-free days and symptom-free nights. The greater improvements in pulmonary function observed with an ICS plus the LABA, salmeterol, occurred within the first week of treatment (at first treatment assessment), and remained significantly greater than those achieved with an ICS plus an LTRA over the duration of the treatment. Moreover, the salmeterol-fluticasone propionate combination (SFC) produces consistently greater improvements in pulmonary lung function and control of asthma than does the addition of an LTRA to fluticasone propionate. In addition, SFC is a more cost-effective treatment option than fluticasone propionate plus montelukast for patients with asthma that is uncontrolled by ICSs alone. Important cost savings can be made with SFC in clinical practice compared with other combinations of ICSs plus salmeterol or ICSs plus LTRAs.

[Pulmonary diseases in the elderly. Problems of pharmacotherapy]

In asthma, inhaled corticosteroids (ICS) can be regarded as disease-modifying drugs. They represent the mainstay of pharmacotherapy of asthma. In elderly, ICS are currently underused. In chronic obstructive pulmonary disease (COPD), there is recent evidence to suggest that ICS may reduce the rate and severity of COPD exacerbations and may improve health-related quality of life. Particularly patients with moderate-to-severe COPD appear to benefit from ICS therapy. In both asthma and COPD, fixed combinations of ICS and long-acting beta 2-agonists may provide clinically meaningful benefits to patients and may represent a further therapeutic advantage.

Pharmacology of airway inflammation in asthma and COPD

The current asthma therapies are not cures and symptoms return soon after treatment is stopped even after long term treatment. Although inhaled glucocorticoids are highly effective in controlling airway inflammation in asthma, they are ineffective in the small group of patients with glucocorticoid-dependent and -resistant asthma. With very few exceptions, COPD is caused by tobacco smoking, and smoking cessation is the only truly effective treatment of COPD available. Current pharmacological treatment of COPD is unsatisfactory, as it does not significantly influence the severity of the disease or its natural course. Glucocorticoids are scarcely effective in COPD patients without concomitant asthma. Bronchodilators improves symptoms and quality of life, in COPD patients, but, with the exception of tiotropium, they do not significantly influence the natural course of the disease. Theophylline is the only drug which has been demonstrated to have a significant effect on airway inflammation in patients with COPD. Here we review the pharmacology of currently used antiinflammatory therapies for asthma and COPD and their proposed mechanisms of action. Recent understanding of disease mechanisms in severe steroid-dependent and -resistant asthma and in COPD, has lead to the development of novel compounds, which are in various stages of clinical development. We review the current status of some of these new potential drugs.

[Pharmacological action and clinical aspects of salmeterol]

Previous systemic beta(2) agonists such as procatrol tablets and tulobuterol patch were developed in Japan to address nocturnal symptoms and maintenance of lung function in asthmatic patients. Salmeterol, a potent and highly selective in beta(2) adrenocepter agonist with a duration of action greater than 12 h, was developed to provide long duration of bronchodilation with binding to a non-active site in the beta(2)-adrenocepter. Salmeterol is administrated via dry power inhalation and clinical studies have showed it has a good efficacy and a good safety profile, similar to inhaled steroids. Indeed, many clinical studies showed that salmeterol demonstrated better efficacy than long-acting beta(2)-agonist oral bronchodilators, theophyllines, and leukotriene-receptor antagonists in asthmatic patients and anticholinergic agents and theophyllines in COPD patients. Salmeterol will provide clinical benefits for Japanese asthma and COPD patients.

[Drug treatment of chronic obstructive pulmonary disease on two levels of patient care: degree of compliance with recommended protocols]

OBJECTIVE

The aims of this study were to identify the drug treatment protocols applied by primary care physicians or pneumologists for patients with stable chronic obstructive pulmonary disease (COPD) in Spain, to determine the agreement between prescription practices and current recommendations and to assess differences between the two levels of patient care.

PATIENTS AND METHODS

The study was observational, descriptive and multicenter. A stratified random sample of patients treated by family physicians or pneumologists was taken for every region in Spain.

RESULTS

Five hundred sixty-eight (63.2%) of the 898 subjects fulfilled COPD diagnostic criteria; 100 were treated by primary care physicians and 460 by pneumologists. In 8 cases the caregiver was unknown. Obstruction was mild-to-moderate in 144 cases and severe in 416. The drugs most commonly prescribed were ipratropium bromide (77.8%), inhaled short-acting beta(2) agonists (65.8%), inhaled corticosteroids (61.0%), long-acting beta(2) agonists (46.4%) and theophyllines (41.3%). Primary care physicians prescribed inhaled short-acting beta 2-agonists most often, whereas pneumologists prescribed anticholinergics most often. In the primary care setting, no differences in treatment protocols were observed based on severity of COPD, degree of dyspnea or quality of life. More consistent differences were seen in treatment by pneumologists. In both settings, prescription was more frequently given when COPD was severe. The most commonly prescribed inhalation device was the Turbuhaler in primary care and the pressurized canister in pneumology.

CONCLUSIONS

Treatments prescribed for COPD patients do not follow current guidelines strictly, particularly in the primary care setting. Different prescription protocols are used at the different levels of patient care.

6. Asthma

The increasing incidence and prevalence of asthma in many parts of the world continue to make it a global health concern. The heterogeneous nature of the clinical manifestations and therapeutic responses of asthma in both adult and pediatric patients indicate that it may be more of a syndrome rather than a specific disease entity. Numerous triggering factors including viral infections, allergen and irritant exposure, and exercise, among others, complicate both the acute and chronic treatment of asthma. Therapeutic intervention has focused on the appreciation that airway obstruction in asthma is composed of both bronchial smooth muscle spasm and variable degrees of airway inflammation characterized by edema, mucus secretion, and the influx of a variety of inflammatory cells. The presence of only partial reversibility of airflow obstruction in some patients indicates that structural remodeling of the airways may also occur over time. Choosing appropriate medications depends on the disease severity (intermittent, mild persistent, moderate persistent, severe persistent), extent of reversibility, both acutely and chronically, patterns of disease activity (exacerbations related to viruses, allergens, exercise, etc), and the age of onset (infancy, childhood, adulthood).

Seretide for obstructive lung disease

Seretide (Advair [North America], GlaxoSmithKline) is an inhaler combination formulation intended for the maintenance therapy of obstructive airways disease. Seretide was developed and made available initially as three multi-dose, dry powder inhaler formulations delivering 50 microg/puff of the long acting beta(2) agonist salmeterol and either 100, 250 or 500 microg/puff of the inhaled corticosteroid fluticasone propionate. In addition to the initial multi-dose dry powder inhaler system (Diskus or Accuhaler), a chlorofluorocarbon (CFC)-free pressurised aerosol formulation has become available. Studied mostly extensively as a maintenance therapy for patients with persistent asthma, the combination inhaler is at least equivalent to its components administered separately and is superior to monotherapy with salmeterol or inhaled corticosteroid in both paediatric and adult populations. The combination has a logical role in the treatment of moderate-to-severe asthma, offering the advantage of increased convenience and possibly improved compliance. In addition to improvements in lung function, symptom scores and quality of life, the combination therapy reduces exacerbation rates, an outcome that contributes to favourable cost-effectiveness. A role as initial maintenance therapy in all forms of persistent asthma is also plausible but there are fewer data concerning the impact of Seretide in milder forms of persistent asthma. Clinical trials are underway to examine the potential role of Seretide in patients with chronic obstructive pulmonary disease (COPD). Salmeterol has been shown to be an effective first-line bronchodilator in COPD and fluticasone has been shown to reduce the frequency and or severity of exacerbations in COPD patients in two key trials. At a time when the prevalence of both asthma and COPD is increasing, Seretide is a valuable step in the management of these common obstructive lung diseases.

Long-acting beta-agonist treatment in patients with persistent asthma already receiving inhaled corticosteroids

International guidelines recommend that long-acting beta-agonists should be considered in patients who are symptomatic despite moderate doses of inhaled corticosteroids. When combined with inhaled corticosteroids they improve asthma symptoms and lung function and reduce exacerbations. The evidence suggests that they are well tolerated. However, they are less effective than inhaled corticosteroids as monotherapy and should not be used alone, although the addition of a long-acting beta-agonist may permit a small reduction in the corticosteroid dose. Both salmeterol and formoterol appear equally effective in improving asthma control. Formoterol, however, has a rapid onset of action and is now being promoted for the relief of acute asthma symptoms. Both drugs provide prolonged protection against exercise-induced bronchospasm. However, this effect rapidly diminishes with continuous therapy and if this is the main aim of treatment, intermittent use may be preferable. When compared with alternative treatments, inhaled long-acting beta-agonists are more effective in controlling asthma symptoms than either theophylline or antileukotriene agents. Bambuterol, an oral prodrug of terbutaline, appears to be as effective as the inhaled long-acting beta-agonists and has the advantage of once daily oral administration. However, the inhaled long-acting beta-agonists are less likely to have systemic adverse effects. There are theoretical concerns that regular beta-agonist treatment may lead to tolerance and a failure to respond to emergency asthma treatment. While there is no doubt that tolerance occurs, there is currently little evidence that this is a clinical problem. Insights into pharmacological as well as therapeutic interactions between inhaled corticosteroids and beta-agonists are providing justification for their use in combination. Guidelines for the management of patients with chronic persistent asthma are likely to require modification to reflect these developments.

Advair: combination treatment with fluticasone propionate/salmeterol in the treatment of asthma

Several classes of medications are available for the treatment of asthma, and often they must be taken concurrently to achieve asthma control. Based on the understanding of asthma as an inflammatory disease, the National Heart Lung and Blood Institute guidelines provide a stepwise approach to pharmacologic therapy. Corticosteroid therapy, principally inhaled corticosteroid (ICS) therapy, is considered the most effective anti-inflammatory treatment. In cases of moderate-to-severe persistent asthma, the addition of a second long-term control medication to ICS therapy is one recommended treatment option. A combination-product inhaler (Advair, Seretide) was developed to treat both the inflammatory and bronchoconstrictive components of asthma by delivering a dose of the ICS, fluticasone propionate, and a dose of the long-acting beta2-adrenergic (LABA) bronchodilator, salmeterol. The Advair Diskus is available in 3 strengths of fluticasone propionate (100, 250, and 500 microg) and a fixed dose (50 microg) of salmeterol. Combination treatment with both ICS and LABA provides greater asthma control than increasing the ICS dose alone, while at the same time reducing the frequency and perhaps the severity of exacerbations. Furthermore, salmeterol added to ICS therapy provides superior asthma control compared with the addition of leukotriene modifiers or theophylline. The superior control is likely a consequence of the complementary actions of the drugs when taken together, including the activation of the glucocorticoid receptor by salmeterol. By combining anti-inflammatory treatment with a long-acting beta2-agonist in a single inhaler (1 inhalation twice daily), physicians can provide coverage for both the inflammatory and bronchoconstrictive aspects of asthma without introducing any new or unexpected adverse consequences. The most common drug-related adverse events were those known to be attributable to the constituent medications (ICS therapy and/or LABA therapy). Although the benefits of combined ICS plus LABA therapy can be achieved with separate inhalers, the convenience of the combination product may improve patient adherence and may therefore reduce the morbidity of asthma.

[Treatment of chronic bronchitis and chronic pulmonary obstructive disease in primary care]

In spite of the recent publication of various guidelines for the treatment of chronic bronchitis and chronic obstructive pulmonary disease (COPD), no studies have investigated whether or not they are being implemented by caregivers. Our aim was to determine what treatment protocols for patients with chronic bronchitis and COPD are most commonly applied by general practitioners in Spain and to identify factors associated with the prescription of certain drugs. A standardized questionnaire was administered to 268 general practitioners working in the 17 autonomous communities of Spain. The stratified sample of respondents was selected to reflect the population of each community. Valid information on 2,414 patients was collected. Men accounted for 74% of the patients. Mean age was 67 years (SD = 10). Lung function data were available for 1,130 (47%) and mean FEV1 was 1,523 ml (56% of the theoretical reference value). Patients without lung function data in spite of having signs of severe symptoms had suffered more acute exacerbations and generated more visits to the emergency room and to their primary care doctors in the preceding year than had patients who had undergone lung function testing (p < 0.03; p < 0.001; p < 0.003, respectively). The treatments most often prescribed were short-acting inhaled beta-2 agonists (56%), inhaled corticoids (47%), theophylline-containing drugs (43%), and long-lasting beta-2 agonists (41%). Patients who had not undergone function tests received more mucolytics (47% versus 27%, p < 0.001) and fewer anticholinergics (20% versus 35%, p < 0.001). The factor most highly associated with prescription of all drugs was severity of disease measured by dyspnea. Treatment protocols for chronic bronchitis and COPD in general practice in many aspects show differences from current guidelines. Noteworthy is the extensive use of inhaled corticoid therapy and long-lasting beta-2 adrenergic agonists and the infrequent prescription of anticholinergics. The lack of lung function data is associated with poor pharmacologic management of disease and higher rates of morbidity.

The role of theophylline in asthma management

Views on the appropriate use of theophylline in asthma management have varied substantially over the past decades. The recent emphasis on potential anti-inflammatory effects of theophylline has only added to the debate. In current guidelines, theophylline has been positioned mainly as a form of "add-on" therapy in moderate to severe persistent asthma. The purpose of this review is to analyze whether recent developments have been made that allow for a further positioning of theophylline in the treatment of asthma.

Dose-response relationships in determining the safety:efficacy ratio

The development of inhaled agonists selective for beta 2-adrenoceptors and high potency corticosteroids has improved the treatment of asthma. The delivery of the drugs to the site of action reduces the systemic exposure and hence reduces adverse systemic events. Together, these factors have resulted in improved toxicity: therapeutic ratios. Long-acting beta 2-agonists, such as salmeterol and formoterol, and high efficacy corticosteroids, such as fluticasone propionate and budesonide, now are available for clinical use. Because suboptimal treatment of asthma causes increased morbidity and mortality, and increased costs to society, these compounds are of particular value. Risk factors associated with fatal and near-fatal asthma have been identified, and it would appear that drug treatment by metered dose inhaler per se does not cause increased asthma fatality as an independent risk factor.