A comparative study of the clinical efficacy of nedocromil sodium and placebo. How does cromolyn sodium compare as an active control treatment?

Benzopyrone, a privileged scaffold in drug discovery: An overview of FDA-approved drugs and clinical candidates

Natural products have always served as an important source of drugs for treating various diseases. Among various privileged natural product scaffolds, the benzopyrone class of compounds has a substantial presence among biologically active compounds. One of the pioneering anticoagulant drugs, warfarin approved in 1954 bears a benzo-α-pyrone (coumarin) nucleus. The widely investigated psoriasis drugs, methoxsalen, and trioxsalen, also contain a benzo-α-pyrone nucleus. Benzo-γ-pyrone (chromone) containing drugs, cromoglic acid, and pranlukast were approved as treatments for asthma in 1982 and 2007, respectively. Numerous other small molecules with a benzopyrone core are under clinical investigation. The present review discusses the discovery, absorption, distribution, metabolism, excretion properties, and synthetic approaches for the Food and Drug Administration-approved and clinical-stage benzopyrone class of compounds. The role of the pyrone core in biological activity has also been discussed. The present review unravels the potential of benzopyrone core in medicinal chemistry and drug development.

Managing Chronic Cough Due to Asthma and NAEB in Adults and Adolescents: CHEST Guideline and Expert Panel Report

BACKGROUND

Asthma and non-asthmatic eosinophilic bronchitis (NAEB) are among the commonest causes of chronic cough in adults. We sought to determine the role of non-invasive measurements of airway inflammation, including induced sputum and fractional exhaled nitric oxide, in the evaluation of cough associated with asthma, and what the best treatment is for cough due to asthma or NAEB.

METHODS

We undertook three systematic reviews of randomized controlled trials and observational trials of adults and adolescents > 12 years of age with a chronic cough due to asthma or NAEB. Eligible studies were identified in MEDLINE, CENTRAL, and SCOPUS and assessed for relevance and quality. Guidelines were developed and voted upon using CHEST guideline methodology.

RESULTS

Of the citations reviewed, 3/1,175, 53/656, and 6/134 were identified as being eligible for inclusion in the three systematic reviews, respectively. In contrast to established guidelines for asthma therapies in general and the inclusion in some guidelines for a role of biomarkers of airway inflammation to guide treatment in severe disease, the evidence of specific benefit related to the use of non-invasive biomarkers in patients with chronic cough due to asthma was weak. The best therapeutic option for cough in asthma or NAEB is inhaled corticosteroids followed by leukotriene receptor antagonism.

CONCLUSIONS

This guideline offers recommendations on the role of non-invasive measurements of airway inflammation and treatment for cough due to asthma or NAEB based on the available literature, and identifies gaps in knowledge and areas for future research.

Asthma: diagnosis and management

The diagnosis and management of asthma continue to be of critical importance, as recent trends have demonstrated its increasing prevalence, morbidity, and perhaps mortality. Because current treatments for asthma are effective and safe, it is important to diagnose asthma early and to use treatments effectively, particularly those directed toward airway inflammation. The diagnostic measures and array of medications, both those currently available and on the horizon, provide an armamentarium for effective diagnosis, management, and monitoring of asthma. In the coming years, it is expected that additional testing modalities will be available for more precise monitoring of asthma control, and an increased understanding of pharmacogenetics will enable the tailoring of asthma medications to specific patients, providing customized therapy to maximize asthma control.

Comparative effect of triamcinolone, nedocromil and montelukast on asthma control in children: A randomized pragmatic study

Asthma severity can be judged by measurements of symptoms, lung function, and medication requirements. The objective was to compare the effect of a 4-wk monotherapy with low-dose triamcinolone, montelukast and nedocromil on asthma control, lung function, eosinophil blood count, and bronchial hyper-reactivity in children with mild to moderate asthma allergic to dust mite. Two hundred fifty-six children, aged 6-18 yr, with mild to moderate asthma, participated in an 8-wk study. This was a three-arm, randomized no blinding or placebo pragmatic trial comparing the effect of triamcinolone acetonide (400 microg/day), inhaled nedocromil and montelukast sodium on clinical parameters of asthma [score, forced expiratory volume in 1 s (FEV(1))], PC20H, and eosinophil blood count. Two hundred forty-six children completed the study. After 4 wk of treatment with triamcinolone and montelukast, FEV(1) and PC20H significantly increased, and mean total symptoms score and mean number of eosinophil count in serum significantly decreased. Triamcinolone had a stronger effect on PC20H than montelukast. Nedocromil improved total asthma symptoms score and lung function. There was a reduction in the daytime and night-time symptom scores after treatment with all three drugs. Triamcinolone and montelukast had a stronger effect on asthma symptoms than nedocromil. There were statistically significant differences in reduction of nocturnal asthma symptoms between the triamcinolone and nedocromil groups (p < 0.001) and between montelukast and nedocromil (p = 0.001) groups, but not between the triamcinolone and montelukast groups. There was a reduction in beta-agonists use after treatment with all three drugs, with the strongest effect of triamcinolone. The study showed the strongest effect of low-dose inhaled steroids on clinical symptoms, lung function, bronchial hyper-reactivity and eosinophil blood count when compared to other asthma medications.

Treatment of childhood asthma: how do the available options compare?

The National Asthma Council of Australia suggests that "the aim of preventive therapy should be to enable patients to enjoy a normal life (comparable with that of non-asthmatic children), with the least amount of medication and at minimal risk of adverse events. The level of maintenance therapy should be determined by symptom control and lung function in the interval periods." The British Thoracic Society/Scottish Intercollegiate Guidelines Network states that the aims of the pharmacological treatment of asthma should be to control symptoms, prevent exacerbations and achieve the best possible lung function with minimal adverse effects. We have used the current published international guidelines to highlight the international differences in management recommendations, and compared the possible pharmacological options with a focus on the above ideals. Cromones have been used for many years in childhood asthma. Most evidence suggests they now have little role. Regarding inhaled corticosteroids (ICS), beclomethasone and budesonide are essentially similar in their efficacy. Fluticasone propionate is equally as effective at one-half the equivalent dose of budesonide or beclomethasone. Adverse effects are rare in dosages <400 microg/day of budesonide and beclomethasone or <200 microg/day of fluticasone propionate, but may occur in individual patients. Relevant clinical adverse effects are rare and pharmacological systemic effects are less noticeable with budesonide and fluticasone propionate than with beclomethasone, but data are conflicting. Long-acting beta2-adrenoceptor agonists (beta2-agonists) are recommended once low-dose ICS have failed to control symptoms. The main pharmacological difference between the agents is that formoterol is a full beta2-adrenergic agonist, whereas salmeterol is a partial agonist at the beta2-adrenoceptor and has a unique pharmacological action. The main clinical distinction between these two agents is that their onset of bronchodilation differs. Bronchodilation begins at about 3 minutes after inhalation of formoterol, which is similar to the short-acting agents, whereas salmeterol has a much slower onset of action at about 15-30 minutes. The many in vitro differences between the two drugs are probably not clinically relevant. There are no comparative pediatric data on the leukotriene modifiers to make clear recommendations.

Treatment options for initial maintenance therapy of persistent asthma: a review of inhaled corticosteroids and leukotriene receptor antagonists

Inhaled corticosteroids (ICSs) are recognized as the cornerstone of asthma therapy. They are considered to be the most effective anti-inflammatory medication currently available for the treatment of persistent asthma, regardless of its severity. Leukotriene receptor antagonists (LTRAs) are also used as initial maintenance therapy in patients whose asthma is uncontrolled by bronchodilators alone. There are now sufficient data available to allow a comparison of the relative effectiveness and cost-effectiveness of LTRAs and ICSs as initial maintenance therapy. The consensus from the studies reviewed in this article demonstrates that ICSs are more effective than LTRAs as initial maintenance therapy. In particular, studies on fluticasone propionate have shown that it was more effective than LTRAs in clinical outcomes: producing greater improvements in lung function and asthma control; as measured by either forced expiratory volume in 1 second (FEV1) or peak expiratory flow (PEF); by a greater reduction in daytime and night-time asthma symptoms; and short-acting beta2-agonist use. This superiority was also seen when patients were switched from an LTRA to fluticasone propionate. Similar findings have been demonstrated with beclomethasone dipropionate (BDP), showing that, in adults, this inhaled steroid also had a greater effect on pulmonary function and symptom scores than did LTRAs. Quality of life assessments showed that fluticasone propionate achieved improvements that were deemed to be clinically meaningful; these changes were significantly greater than those achieved with LTRAs. However, questionnaire-based patient preference studies comparing BDP with LTRAs showed that children and adolescents generally preferred an LTRA to BDP. A number of comparative analyses showed that inhaled fluticasone propionate is more cost-effective than either montelukast or zafirlukast; these analyses used cost per symptom-free day and cost per successfully treated patient as outcome measures, from the perspective of a third-party payer. In general, these results were supported by resource utilisation studies in real-world settings. Asthma treatment guidelines (e.g. GINA, 2002) recommend combination therapy with ICSs and a long-acting beta2-agonist as initial maintenance therapy if the disease is of sufficient severity. Studies that assessed the effectiveness, cost-effectiveness, and quality of life achieved with a salmeterol fluticasone propionate combination as initial maintenance therapy also showed it to be superior to LTRAs. In conclusion, in terms of efficacy and quality of life, fluticasone propionate is more effective than LTRAs as initial maintenance therapy and is associated with significantly lower healthcare costs and less frequent use of healthcare resources than LTRAs. There is also evidence to suggest that initial maintenance therapy with the combination of an inhaled steroid plus a long-acting beta-agonist bronchodilator may be a more effective option for the management of persistent asthma than treatment with a single-controller agent alone (ICS or LTRA).

Pharmacotherapy of chronic cough in adults

Chronic cough is a debilitating symptom for which patients commonly seek medical attention. Among adult non-smokers who are not taking an angiotensin-converting enzyme inhibitor and have a normal or near normal chest radiograph, postnasal drip syndrome caused by a variety of rhinosinus conditions, asthma and non-asthmatic eosinophilic bronchitis and gastro-oesophageal reflux disease singly or in combination, are the most common diagnoses underlying chronic cough. Pharmacotherapy for chronic cough can be either specific or non-specific. Specific therapy is preferable and the most effective as it is directed at the aetiologies and pathophysiological mechanisms responsible for cough. In contrast, non-specific therapy is used only in limited clinical settings, as it is directed at the symptom rather than underlying aetiologies and aims only to control, rather than eliminate cough.

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).

Exercise-induced bronchospasm in the elite athlete

The term exercise-induced bronchospasm (EIB) describes the acute transient airway narrowing that occurs during and most often after exercise in 10 to 50% of elite athletes, depending upon the sport examined. Although multiple factors are unquestionably involved in the EIB response, airway drying caused by a high exercise-ventilation rate is primary in most cases. The severity of this reaction reflects the allergic predisposition of the athlete, the water content of the inspired air, the type and concentration of air pollutants inspired, and the intensity (or ventilation rate) of the exercise. The highest prevalence of EIB is seen in winter-sport populations, where athletes are chronically exposed to cold dry air and/or environmental pollutants found in indoor ice arenas. When airway surface liquid lost during the natural warming and humidification process of respiration is not replenished at a rate equal to the loss, the ensuing osmolarity change stimulates the release of inflammatory mediators and results in bronchospasm; this cascade of events is exacerbated by airway inflammation and airway remodelling. The acute EIB response is characterised by airway smooth muscle contraction, membrane swelling, and/or mucus plug formation. Evidence suggests that histamine, leukotrienes and prostanoids are likely mediators for this response. Although the presence of symptoms and a basic physical examination are marginally effective, objective measures of lung function should be used for accurate and reliable diagnosis of EIB. Diagnosis should include baseline spirometry, followed by an appropriate bronchial provocation test. To date, the best test to confirm EIB may simply be standard pulmonary function testing before and after high-intensity dry air exercise. A 10% post-challenge fall in forced expiratory volume in 1 second is used as diagnostic criteria. The goal of medical intervention is to limit EIB exacerbation and allow the athlete to train and compete symptom free. This is attempted through daily controller medications such as inhaled corticosteroids or by the prophylactic use of medications before exercise. In many cases, EIB is difficult to control. These and other data suggest that EIB in the elite athlete is in contrast with classic asthma.

Balancing Safety and Efficacy in Pediatric Asthma Management

In the treatment of childhood asthma, balancing safety and efficacy is key to achieving optimal therapeutic benefit. Inhaled corticosteroids (ICS), because of their efficacy, remain a cornerstone in managing persistent pediatric asthma, but also are associated with significant adverse effects, including growth suppression. Consequently, careful attention must be given to balancing their safety and efficacy, which should include an understanding of airway patency and systemic absorption (dose, disease severity, propellant and lipophilicity of inhalant), bioavailability (inhalation technique, propellant, delivery devices, and hepatic first-pass metabolism), techniques for using minimum effective doses (dosing time, add-on therapy), and reduction of other exacerbating conditions (allergens, influenza, upper-respiratory diseases). The growth-suppressive effects of ICS may be most evident in children with: 1) mild asthma because the relatively high airway patency may facilitate increased levels of deposition and steroid absorption in more distal airways, and 2) evening dosing that may reduce nocturnal growth hormone activity. A step-down approach targeting a minimum effective dose and once-daily morning dosing is suggested for achieving the most acceptable safety/efficacy balance with ICS. The achievement of regular, safe, and correct ICS use requires significant knowledge and time for both caregiver and patient. Chromones, methylxanthines, long-acting β-agonists, and leukotriene receptor antagonists are currently available alternatives to ICS for the control of persistent childhood asthma. Chromones are safe but, like methylxanthines, are difficult to use and frequently result in compromised effectiveness. Long-acting β-agonists are not recommended as monotherapy for persistent asthma. Several factors that support leukotriene receptor antagonists as a therapeutic option for mild-to-moderate persistent pediatric asthma include established efficacy, good safety profiles, and simple, oral dosing. Physicians must evaluate and compare the balance of safety and efficacy for each agent to determine the appropriate asthma therapy for individual patients.

Double-blind, randomized, placebo-controlled trial of effect of nedocromil sodium on clinical and inflammatory parameters of asthma in children allergic to dust mite

BACKGROUND

The purpose of this study was to determine the clinical effect of nedocromil sodium and its relationship with serum levels of inflammatory mediators by monitoring lung function and noninvasive markers of airway inflammation, such as eosinophil blood counts; serum ECP, sIL-2R, IL-4 and sICAM; and total IgE. Anti-inflammatory medications cause a reduction in the markers of airway inflammation, decrease the intensity of airway hyperresponsiveness, and improve clinical symptoms of asthma. Among the available choices is nedocromil sodium, which is favored in the treatment of asthmatic children due to its very mild side-effects. It has been previously shown to improve the clinical parameters of asthma, but there are limited data on its effect on inflammatory mediators in the serum of asthmatic children.

METHODS

In this double-blind, randomized, placebo-controlled 8-week trial, 39 children, aged 9-16 years, with moderate atopic asthma were randomly allocated to receive either nedocromil sodium, two puffs twice daily, 0.002 g/puff, or placebo, two puffs twice daily. The primary end points were the clinical parameters of asthma measured by asthma symptom score, FEV1, and PC20H. Other end points included the serum levels of various inflammatory markers - ECP, sIL-2R, IL-4, sICAM, and IgE.

RESULTS

Clinical and inflammatory parameters improved with the use of nedocromil sodium, compared with placebo. Nedocromil significantly decreased serum levels of inflammatory markers, as shown in the following table. No correlation was found between any of the measured parameters.

CONCLUSION

Nedocromil sodium provided effective anti-inflammatory treatment for children with moderate atopic asthma.

[Antiallergy drugs and respiratory diseases in children]

Second generation antihistamines (anti H1) are effective for seasonal and perennial rhinoconjunctivitis curative or preventive treatment in children. They are better tolerated than first generation drugs. They probably do not act specifically against asthma itself, but are nevertheless useful for relief of nasal obstruction, which is an asthmogenic factor frequently linked with bronchial asthma. The therapeutic relevance of oral ketotifen and inhaled chromones (sodium cromoglycate, nedocromil sodium) is unequally considered among pediatricians. However, their efficacy has been clearly demonstrated as a ground treatment in mild-to-moderate asthmatic children. Chromones are also useful in preventing exercise-induced asthma. Because of their low cost and the lack of potential side effects, and according to the guidelines established in 1997 by the National Heart, Lung and Blood Institute, they should be prescribed at first sight in these indications.

Controlled trial of two formulations of cromolyn sodium in the treatment of asthmatic patients > or = 12 years of age. Intal Study Group

STUDY OBJECTIVES

This multicenter, randomized, double-blind, placebo-controlled, parallel study compared the efficacy and safety of the hydrofluoroalkane (HFA) formulation of cromolyn sodium metered-dose inhaler (MDI) with the chlorofluorocarbon (CFC) formulation in asthmatic patients > or = 12 years old over a 12-week period.

DESIGN

Stable asthmatics using only currently marketed cromolyn sodium and as-needed inhaled beta2-agonists were randomly assigned to treatment with HFA cromolyn sodium, CFC cromolyn sodium, or placebo, administered as two inhalations (2 mg) qid for 12 weeks. Prior to randomization, all patients were required to meet minimum symptom and/or pulmonary function test criteria after discontinuation of cromolyn sodium. Efficacy was assessed by changes in daily symptom scores, albuterol use, peak expiratory flow, pulmonary function measurements, and overall opinions of effectiveness.

RESULTS

A total of 280 patients in 29 centers were randomly assigned to treatment with HFA cromolyn sodium (n = 94), CFC cromolyn sodium (n = 91), or placebo (n = 95). Patients treated with the HFA formulation of cromolyn sodium demonstrated a 28 to 33% improvement over placebo for all symptom scores (p < 0.05) and a 35% improvement over placebo in the use of albuterol MDI (p < 0.05). The patients' opinions of overall effectiveness favored HFA cromolyn sodium (p = 0.011) and CFC cromolyn sodium (p = 0.006) over placebo. The investigators' opinions indicated a statistically significant difference favoring CFC cromolyn sodium compared with both placebo (p < 0.001) and HFA cromolyn sodium (p = 0.042). No statistically significant differences existed among groups in the incidence of treatment-related adverse events.

CONCLUSION

The HFA formulation of cromolyn sodium MDI is a well-tolerated and effective treatment for asthma patients > or = 12 years old. The safety and efficacy profile of the HFA formulation is comparable to that of the CFC formulation.

Early use of inhaled nedocromil sodium in children following an acute episode of asthma

BACKGROUND

Current guidelines on the treatment of childhood asthma recommend the introduction of an anti-inflammatory drug in children who have persistent symptoms and require regular treatment with a bronchodilator. The efficacy and safety of inhaled nedocromil sodium (Tilade Mint aerosol) administered using a Fisonair spacer at a dose of 4 mg three times daily was compared with placebo in the treatment of asthmatic children aged 6-12 years who are symptomatic and recovering from an acute exacerbation of asthma.

METHODS

A group comparative, double blind, placebo controlled trial was performed in children who were recovering from an acute episode of asthma following treatment in the emergency department of the hospital or in children referred from their general practitioner following a wheezing episode and documented evidence of at least two previous episodes of wheezing. A two week baseline period on existing bronchodilator treatment was followed by a 12 week treatment period on either nedocromil sodium (2 mg/puff) or placebo. Both treatments were administered using a Fisonair spacer at a dose of two puffs three times daily. Changes from baseline values in daytime asthma and night time asthma symptom scores, usage of rescue bronchodilators, mean peak expiratory flow (PEF) recorded twice daily on diary cards, patients' opinion of treatment, and withdrawals due to treatment failure were measured during the primary treatment period (last six weeks of treatment).

RESULTS

One hundred and forty two children aged 6-12 years entered the baseline period. Sixty three were withdrawn due to failure to meet the entry criteria (18) or the criteria for asthma symptom severity (15) or reversibility (9), because they developed uncontrolled asthma (2), because they took disallowed treatment (2), or for other non-trial related reasons (17). Seventy nine patients (46 boys) of mean age 8. 8 years entered the treatment period. There were significant differences in the changes from baseline values during the last six weeks of treatment in favour of nedocromil sodium compared with placebo in the primary variables of daytime asthma and night time asthma, morning and evening PEF, and the usage of rescue inhaled bronchodilators; 53% of patients reported nedocromil sodium to be very or moderately effective compared with 44% placebo. Improvement in asthma symptoms, PEF, and reduction in use of rescue bronchodilators did not reach statistical significance until after six weeks of treatment. Twenty two patients were withdrawn or dropped out during the treatment phase, 12 due to uncontrolled asthma or persistence of asthma symptoms, four due to suspected adverse drug reactions (nedocromil sodium 3 (headaches 2, angio-oedema/urticaria 1), placebo 1(persistent cough)), and six due to non-treatment related reasons. Seventy one adverse events were reported by 27 patients in the nedocromil group and 75 by 30 patients in the placebo group.

CONCLUSIONS

Asthma symptoms, use of bronchodilators, and lung function can be improved significantly in children recovering from an acute exacerbation of asthma or wheeze and currently receiving treatment with bronchodilators alone by the addition of inhaled nedocromil sodium at a dose of 4 mg three times daily administered using a Fisonair holding chamber.

Alternative agents for anti-inflammatory treatment of asthma

Recent guidelines for the management of asthma have emphasized the role of inflammation in persistent asthma. Medications with anti-inflammatory properties are recommended as the primary long-term-control medications. Of the available choices of long-term-control medications, inhaled corticosteroids are the preferred medication. A literature review of the available studies supports this recommendation of inhaled corticosteroids as the preferred agents for long-term control. Other long-term-control medications--specifically nedocromil, theophylline, and leukotriene modifiers, but not cromolyn--can supplement the beneficial effect of inhaled corticosteroids on pulmonary function and symptom control. Long-acting beta2-adrenergic agonists can also provide an additive clinical benefit to inhaled corticosteroids on symptom control and pulmonary function, but they do not provide additional anti-inflammatory effect. Extended long-term studies of each of the long-term-control medications with anti-inflammatory actions are needed to assess their specific effect on airway remodeling and on the natural history of asthma.

Evaluation of a non-chlorofluorocarbon formulation of cromolyn sodium (Intal) metered-dose inhaler versus the chlorofluorocarbon formulation in the treatment of adult patients with asthma: a controlled trial

BACKGROUND

Cromolyn sodium is a nonsteroidal inhaled antiinflammatory agent for the treatment of asthma. As with other pressurized aerosol medications, the metered-dose inhaler (MDI) formulation currently contains chlorofluorocarbon (CFC) propellants. Because of their harmful effects on the environment CFCs are now generally banned from production and use. Alternative propellants under production for MDIs include derivatives of hydrofluoroalkane (HFA). This study uses HFA-227 in an MDI formulation of cromolyn sodium.

OBJECTIVES

The objectives of the study were (1) to examine the efficacy and safety of an HFA formulation of cromolyn sodium (Intal) MDI and (2) to compare the HFA formulation with the CFC formulation.

METHODS

A multicenter, randomized, double-blind, placebo-controlled, parallel study with two active groups (HFA-cromolyn sodium [n = 113] and CFC-cromolyn sodium [n = 107]) and a placebo-treated group (n = 105).

RESULTS

Patients treated with either formulation of cromolyn sodium MDI showed a statistically significant (p < 0.05) improvement of 12% to 18% compared with placebo in symptom summary score, daytime asthma symptoms, and albuterol use. No statistically significant differences were observed in pulmonary function. Patient and physician opinions of overall effectiveness favored HFA-cromolyn sodium over placebo (p = 0.01), with no other significant between-treatment differences. No statistically significant differences existed among groups in the incidence of treatment-related adverse events.

CONCLUSION

The HFA formulation of cromolyn sodium MDI is a well- tolerated and active alternative treatment for asthma patients aged 12 years and more.