Beta2-agonist tolerance and exercise-induced bronchospasm. Combination drug therapy for the prevention of exercise-induced bronchoconstriction in children. Short-term regular beta 2-adrenergic agonists treatment is safe in mild asthmatics taking low doses of inhaled steroids. A comparison of regular with intermittent bronchodilators in asthma patients on inhaled steroids. Tolerance to the nonbronchodilator effects of inhaled beta 2-agonists in asthma. Effect of different antiasthmatic treatments on exercise-induced bronchoconstriction in children with asthma. Budesonide/formoterol combination therapy as both maintenance and reliever medication in asthma. Exercise-induced bronchoconstriction as an expression of bronchial hyperreactivity: a study of its mechanisms in children. Nedocromil, a mucosal and connective tissue mast cell stabilizer, inhibits exercise-induced asthma. Effect of inhaled fluticasone with and without salmeterol on airway inflammation in asthma. Equivalence of salbutamol 200 microg four times daily propelled by propellants 11 and 12 or HFA 134a in mild to moderate asthmatics. Eastern European study group. Changes in methacholine induced bronchoconstriction with the long acting beta 2 agonist salmeterol in mild to moderate asthmatic patients. An antiinflammatory effect of salmeterol, a long-acting beta(2) agonist, assessed in airway biopsies and bronchoalveolar lavage in asthma. Repository dexamethasone in the treatment of acute bronchial asthma. Proventil HFA prevents exercise-induced bronchoconstriction in children. Asthma control during and after cessation of regular beta 2-agonist treatment. Proventil HFA provides protection from exercise-induced bronchoconstriction comparable to proventil and ventolin. The long-acting beta2-agonist salmeterol xinafoate: effects on airway inflammation in asthma. Initiation of maintenance treatment of persistent asthma: salmeterol/fluticasone propionate combination treatment is more effective than inhaled steroid alone. A comparison of four beta-adrenoceptor antagonists in patients with asthma.
The effect of regular inhaled beta-agonist on the treatment of exercise-induced bronchoconstriction was studied. Eight subjects with exercise-induced bronchoconstriction took 1 week each of salbutamol 200 microg qid or placebo in a random-order, double-blind, crossover study. They then withheld this treatment for 8 hours before performing a dry-air, sub-maximal exercise challenge at a work-rate previously shown to induce a 15% fall in forced expiratory volume in 1 second (FEV1). Five minutes after exercise, they inhaled salbutamol 100, 100, and 200 microg at 5-minute intervals. The mean pre-exercise FEV1 was similar on both study days. However, pretreatment for 1 week with salbutamol led to a significantly greater fall in FEV1 after exercise. The FEV1 remained lower than during the placebo arm despite the administration of salbutamol after exercise. This difference persisted 25 minutes after exercise. It is concluded that regular beta-agonist treatment leads to increased exercise-induced bronchoconstriction and a suboptimal bronchodilator response to beta-agonist. The data suggest that previous regular beta-agonist treatment may lead to a failure to respond to emergency bronchodilator treatment during an acute asthma attack and support current opinion that regular short-acting beta-agonist therapy should not be used to treat asthma. Sequential administration of a beta-agonist and cromolyn or nedocromil before exercise is recommended for patients whose symptoms are not controlled by beta-agonists alone; however, this practice reduces compliance.
                To evaluate the effectiveness of a new pre-combined aerosol formulation (salbutamol and nedocromil) in preventing exercise-induced bronchoconstriction and to compare it to salbutamol alone.
                Twelve children with asthma were studied in a double-blind, double-dummy, randomized, crossover, placebo-controlled design to compare the protective effect of salbutamol and a new pre-combined salbutamol/nedocromil formulation against exercise-induced bronchoconstriction. The drugs were delivered by a metered-dose inhaler (salbutamol, 200 microg; salbutamol/nedocromil, 200 microg/4 mg; placebo, 2 puffs) 20 minutes before exercise.
                Both active drugs were significantly more protective than placebo but there was no difference between them. Complete protection was obtained in 12/12, 10/12, and 1/12 subjects for the salbutamol/nedocromil combination, salbutamol alone and placebo, respectively.
                Although inhaled beta-agonists alone are highly efficacious in preventing exercise-induced bronchoconstriction, a minority of patients exists for whom a combined treatment with salbutamol and nedocromil is advantageous. This group may represent a subpopulation of subjects who release more, or different, mediators in response to exercise. Regular treatment with beta 2-adrenergic agonists is controversial in bronchial asthma. To investigate whether beta 2-adrenergic agonists can be used safely if associated with low doses of inhaled steroids, for a short period, without a deterioration of asthma control, we have examined 24 mild asthmatics. In a parallel, double-blind, placebo-controlled study, 1 week of run-in and run-out period framed 3 weeks of treatment. All patients received inhaled beclomethasone dipropionate (BDP 250 micrograms t.i.d.); after 1 week, 12 patients inhaled 400 micrograms of broxaterol and 12 patients received placebo t.i.d. FVC, FEV1, PD20-FEV1 methacholine, morning and evening PEF, and PEF amplitude % mean were measured before, during, and after treatment. No significant changes were noted in patients receiving inhaled broxaterol. There were no differences in symptoms and the use of rescue medication (salbutamol spray). We conclude that short-term regular treatment with beta 2-adrenergic agonists is not associated with a deterioration in asthma control in mild asthmatics inhaling low doses of steroids. The aim of this study was to compare the effect of regular versus intermittent (p.r.n.) bronchodilators on bronchial reactivity and asthma control in patients on concomitant inhaled corticosteroids. We studied 12 patients with asthma in a prospective, randomised, single-blind, single-dummy, three-period crossover trial comparing placebo (2 puffs t.d.s.), salbutamol (200 micrograms t.d.s.) and oxitropium bromide (200 micrograms t.d.s.) for 28 days each. Computerised spirometry and bronchial reactivity to histamine were obtained on entry and after each treatment period. Symptom scores, use of rescue bronchodilator and peak expiratory flow rates were recorded daily. There were no significant differences in bronchial hyperreactivity between the salbutamol, oxitropium and placebo treatment periods. There were no significant differences in baseline FEV1, FEF25-75%, symptom scores, use of rescue bronchodilator or morning and evening PEFR between treatment periods. Intermittent beta agonist therapy is as effective as regular therapy in terms of asthma control and bronchial hyperreactivity in patients on concomitant inhaled corticosteroid therapy. Since intermittent therapy achieves similar results with significantly lower beta agonist consumption, the data support current recommendations that beta agonists should be taken on a p.r.n. basis in asthma patients on inhaled steroids. Tolerance to the direct bronchodilator effects of beta 2-agonists does not appear to occur in asthma. However, it is not known whether this is true for the nonbronchodilator effects of these agents, which protect the airways against bronchoconstrictive stimuli.
                We investigated whether tolerance develops to the protective effect of inhaled terbutaline on airway responsiveness to the bronchoconstrictors methacholine (which acts directly on airway smooth muscle) and AMP (which acts indirectly by stimulating the release of mediators from mast cells) during sustained treatment with terbutaline. In a randomized, double-blind, crossover study, 12 patients with mild asthma each inhaled a single dose of terbutaline (500 micrograms) or placebo before a challenge with a series of doubling doses of inhaled methacholine or AMP, before and after treatment for seven days with 500 micrograms of terbutaline four times daily or placebo.
                Before the seven days of treatment with terbutaline, a single dose of terbutaline reduced airway responsiveness to methacholine by 2.7 doubling doses (95 percent confidence interval, 1.9 to 3.5), but it had an even greater protective effect against AMP, reducing airway responsiveness by 3.8 doubling doses (95 percent confidence interval, 2.7 to 4.9; P less than 0.001). After seven days of treatment with terbutaline, the protective effect of terbutaline against methacholine decreased to 2.2 doubling doses (95 percent confidence interval, 1.3 to 3.0; P = 0.04), and that against AMP decreased even more, to 1.7 doubling doses (95 percent confidence interval, 1.1 to 2.4; P less than 0.001). By contrast, the bronchodilator response to terbutaline was unchanged during seven days of treatment with this agent.
                We observed tolerance to the nonbronchodilator actions of the inhaled beta 2-agonist terbutaline in patients with mild asthma, an effect that may be more pronounced in mast cells than in bronchial smooth muscle. This property of beta-agonists may constitute a drawback to their regular use in patients with asthma. Exercise-induced bronchoconstriction occurs in a large proportion of children with asthma, limiting everyday activities important for their physical and social development.
                The purpose of this randomized, double-blind, placebo-controlled study was to compare the ability of different patterns of antiasthmatic treatment, recommended in childhood asthma, to protect patients from exercise-induced bronchoconstriction.
                Children 6 to 18 years of age with atopic asthma were randomized to a 4-week, placebo-controlled, double-blind trial. Patients were randomly allocated to receive daily 200 microg budesonide (twice daily, 100 microg per dose) + 9 microg formoterol (twice daily, 4.5 microg per dose; n = 20); 200 microg budesonide + 5 or 10 mg montelukast (once daily at bedtime; n = 20); 5 or 10 mg montelukast (n = 20); 200 microg budesonide (n = 20); or placebo (n = 20). A standardized treadmill exercise challenge was performed before and after treatment.
                Exercise-induced bronchoconstriction, reflected by area under the curve for the FEV1 values from exercise over the 20-minute period and by maximum percent fall in FEV1 after exercise, was significantly diminished after 4 weeks in all active treatment groups, and compared with placebo. Exercise-induced bronchoconstriction protection improved more significantly in the budesonide + montelukast and montelukast groups compared with other therapeutic options.
                These data indicate differences in effects on exercise-induced bronchoconstriction between therapeutic options recommended in childhood asthma. Control of childhood asthma with exercise-induced bronchoconstriction can be obtained by using regular controller treatment. Asthma control is improved by combining inhaled corticosteroids with long-acting beta2-agonists. However, fluctuating asthma control still occurs. We hypothesized that in patients receiving low maintenance dose budesonide/formoterol (bud/form), replacing short-acting beta2-agonist (SABA) reliever with as-needed bud/form would provide rapid symptom relief and simultaneous adjustment in antiinflammatory therapy, thereby reducing exacerbations. In this double-blind, randomized, parallel-group study, 2,760 patients with asthma aged 4-80 years (FEV1 60-100% predicted) received either terbutaline 0.4 mg as SABA with bud/form 80/4.5 microg twice a day (bud/form + SABA) or bud 320 microg twice a day (bud + SABA) or bud/form 80/4.5 microg twice a day with 80/4.5 microg as-needed (bud/form maintenance + relief). Children used a once-nocte maintenance dose. Bud/form maintenance + relief prolonged time to first severe exacerbation (p < 0.001; primary endpoint), resulting in a 45-47% lower exacerbation risk versus bud/form + SABA (hazard ratio, 0.55; 95% confidence interval, 0.44, 0.67) or bud + SABA (hazard ratio, 0.53; 95% confidence interval 0.43, 0.65). Bud/form maintenance + relief also prolonged the time to the first, second, and third exacerbation requiring medical intervention (p < 0.001), reduced severe exacerbation rate, and improved symptoms, awakenings, and lung function compared with both fixed dosing regimens. The mechanism of exercise-induced bronchoconstriction (EIB) was studied by observing the protective effects of several aerosol agents in a double-blind, randomised trial. Exercise-induced bronchoconstriction was not affected by placebo, but was reduced by each agent used (p less than 0.001). Blocking the parasympathetic system had the weakest effect, while beta 2 adrenergic stimulation produced the strongest effect which was significantly different from the parasympatholytic (p less than 0.02). The effect of the mast cell stabilizer, sodium cromoglycate (SCG) was found to be intermediate. However in some patients SCG had a stronger effect than the beta 2 adrenergic agonist. A relationship was found between EIB and bronchial hyperreactivity induced by histamine (p less than 0.05). Nedocromil, the disodium salt of a pyranoquinoline dicarboxylic acid, has a similar profile of activity to disodium cromoglycate (DSCG) but appears to be more active in stabilizing mucosal-type mast cells. In a double-blind placebo-controlled trial nedocromil (2 mg) was given by inhalation to eight asthmatic patients prior to a treadmill exercise task. There was a significant reduction in the fall in FEV1 (P less than 0.01) and FVC (P less than 0.05) after nedocromil when compared to placebo. This study indicates that nedocromil might be an effective anti-asthma agent and in addition may help define the role of the mucosal mast cell. The clinical benefit of combining long-acting beta(2)-agonists with inhaled corticosteroids rather than doubling the dose of corticosteroid has been well-documented. However, there are concerns that this might result in a masking of underlying airway inflammation.
                The aim of this study was to test the hypothesis that the addition of the long-acting beta(2)-agonist salmeterol (SALM) to a low dose of the inhaled corticosteroid fluticasone propionate (FP) has a steroid-sparing effect and does not result in a worsening of bronchial inflammation compared to doubling the dose of inhaled corticosteroid.
                Fifty-six asthmatic subjects, previously not well-controlled on inhaled corticosteroids, were randomized to receive 3 months of treatment with inhaled FP 500 microg twice a day (FP 1000) or FP 200 microg twice a day plus SALM 50 microg twice a day (FP 400 + SALM). Fluticasone propionate 200 microg twice a day served as the control (FP400). Bronchial mucosal biopsy specimens, bronchial washings (BW), and bronchoalveolar lavage were obtained before and after treatment. The primary end points for the study were submucosal mast cell and eosinophil counts.
                There was a significant improvement in FEV(1) in the FP400 + SALM group compared to both the FP400 and FP1000 groups. This was accompanied by a significant improvement in peak expiratory flow in the FP400 + SALM group in both the morning and evening compared to the FP1000 group. There were no significant between treatment differences in the change in the number of submucosal mast cells or eosinophils. However, in the FP400 + SALM group there was a significant decrease in submucosal mast cells after 12 weeks of treatment. The addition of SALM to FP was not associated with any increases in airway inflammation in the biopsy specimens, bronchoalveolar lavage, or bronchial washings.
                These findings confirm that addition of SALM to FP has clinical benefits but does not mask or exacerbate airway inflammation and suggest that long-acting beta(2)-adrenoceptor agonists might influence mast cell numbers. The phasing out of chlorofluorocarbons (CFCs) requires the development of an alternative non-ozone depleting propellant for use in pressurized metered dose inhalers (pMDIs). The present study assessed the effects on tolerability and efficacy of a switch from the currently available formulation containing the CFC propellants 11 and 12 to an alternative non-CFC formulation using the propellant hydrofluoroalkane (HFA) 134a in patients with mild to moderate asthma. After a 4-week run-in period during which patients received salbutamol 200 microg four times daily from a CFC pMDI, 547 patients were randomized to 12 weeks of treatment with salbutamol 200 microg four times daily administered from either an HFA 134a pMDI (Ventolin CFC-free; 277 patients) or CFC pMDI (Ventolin, 270 patients). At the end of this period, all patients then received a further 4 weeks of treatment with the same dose of salbutamol via a CFC pMDI (run-out period). On the basis that high doses of beta2-agonists are known to increase heart rate, change in heart rate was selected as the primary outcome variable. Small increases in heart rate were observed during the treatment period and these changes were comparable in both groups; the 90% confidence interval for the treatment differences was within the predefined limits for clinical equivalence (+/- 10 beats min(-1)). The incidence of adverse events was similar in both groups and there were no reports of paradoxical bronchospasm. Furthermore, daily PEF measurements showed comparability in terms of lung function. Symptom scores and use of additional bronchodilator were also similar in both groups. These results demonstrate that salbutamol (800 microg day(-1)), formulated with HFA 134a is equivalent to the current CFC formulation in terms of tolerability and efficacy. Beta-2 agonists protect against non-specific bronchoconstricting agents such as methacholine, but it has been suggested that the protection afforded by long acting beta 2 agonists wanes rapidly with regular treatment.
                The changes in airway responsiveness were investigated during and after eight weeks of regular treatment with salmeterol 50 micrograms twice daily in 26 adult asthmatic patients, 19 of whom were receiving maintenance inhaled corticosteroids. The study was of a randomised, placebo controlled, double blind design. Airway responsiveness to methacholine was measured as PD20 by a standardised dosimeter technique 12 hours after the first dose, at four weeks and eight weeks during treatment (12 hours after the last dose of test medication), and at 60 hours, one week and two weeks after stopping treatment.
                There were no significant differences between the baseline characteristics of the two groups. A significant improvement in PD20 was seen at all points during treatment with salmeterol compared with the placebo group, with no significant fall off with time. PD20 measurements returned to baseline values after cessation of treatment with no significant difference from the placebo group.
                Salmeterol gave significant protection against methacholine induced bronchoconstriction 12 hours after administration. This protection was of small magnitude, but there was no significant attenuation with eight weeks of regular use and no rebound increase in airway responsiveness on stopping treatment in a group of moderate asthmatic patients, the majority of whom were receiving inhaled corticosteroids. The addition of long-acting beta(2) agonists to inhaled corticosteroid (ICS) therapy in symptomatic patients with asthma improves clinical status more than increasing the dose of ICS. It has been suggested that these benefits could be at the cost of an increase in airway inflammation, but few histopathological studies have been performed in the relevant group. In a double-blind, parallel-group, placebo-controlled study, we randomly assigned 50 symptomatic patients with asthma who were receiving ICS (range, 100 -500 microgram/d) to 12 wk of supplementary treatment with salmeterol (50 microgram twice daily) or fluticasone (100 microgram twice daily) or placebo. Bronchial biopsies and BAL were obtained from 45 patients before and after treatment and analyzed. After treatment with salmeterol there was no deterioration of airway inflammation as assessed by mast cells, lymphocytes, or macrophages in BAL or biopsies, but rather a significant fall in EG1-positive eosinophils in the lamina propria (from a median 18.3 to 7.6 cells/mm, p = 0.01), which was not seen after treatment with fluticasone. The only cellular effect of added fluticasone was a decrease in BAL lymphocyte activation. There was a concurrent improvement in clinical status, more marked with salmeterol than with increased ICS. Thus, adding salmeterol to ICS is not associated with increased "allergic" airway inflammation, but conversely with a complementary antieosinophil effect. Fifty-two patients with acute asthma requiring immediate therapy but not hospitalization were studied in an emergency department following conventional therapy with bronchodilators. After discharge, the patients were treated with a controlled regimen of long-acting theophylline and beta-agonist inhalation as necessary. They were randomly assigned to one of three groups using a double blind model. Group A received intramuscular and oral placebos. Group B received intramuscular dexamethasone injection along with oral placebo treatment. Group C received oral dexamethasone by a tapering schedule associated with placebo intramuscular injection. Follow-up was carried out 7 days after the treatment in the emergency room. There were no significant statistical differences in the relapse rate among the three groups. Those patients who received oral or intramuscular dexamethasone had a decrease in the need for beta-agonist inhalation and fewer respiratory symptoms. However, there was no significant statistical difference between groups B and C. It was concluded that repository steroids could reduce the respiratory symptoms and frequency of beta-agonist usage as effectively as oral steroid treatment. However, the steroids do not improve the relapse rate in patients with only mild symptoms. Short-acting inhaled beta2-agonists used just prior to exercise are an effective method for preventing exercise-induced bronchoconstriction (EIB) in children. This was a randomized, single-blind, placebo-controlled, four-period crossover study that compared the effectiveness of albuterol formulated in hydrofluoroalkane-134a (HFA) to albuterol formulated in chlorofluorocarbons (CFCs) and to placebo in protecting asthmatic children age 6-11 from EIB. Patients self-administered either HFA albuterol, two different CFC albuterol products, or placebo 30 min prior to exercise challenge. Spirometry was performed predose and 5, 10, 15, 30, 45, 60, 75, and 90 min after the exercise challenge was completed. The smallest percent change from the predose forced expiratory volume in 1 sec (FEV1) after exercise challenge was similar for the three active treatments, and each of the active treatments was significantly better than placebo. Each active treatment had significantly fewer patients unprotected from EIB (unprotected defined as having >20% fall in FEV1 after exercise challenge) than placebo. Changes in heart rate, blood pressure and electrocardiogram (ECG) intervals were similar for the three active treatments following exercise. HFA albuterol is as effective as albuterol products formulated in CFCs and more effective than placebo in protecting asthmatic children from EIB. It has been suggested that regular treatment with high doses of beta 2-agonists might result in poorer control of asthma and increased bronchial responsiveness. We have examined change in FEV1 (delta FEV1), bronchial reactivity, peak expiratory flow (PEF), and symptoms during and after 3 wk of regular treatment with a relatively low dose of albuterol and broxaterol, a new beta 2-agonist. Eleven subjects 18 to 50 yr of age with mild asthma inhaled albuterol (200 micrograms), broxaterol (400 micrograms), or placebo three times a day for 3 wk with a 2- to 4-wk run-in/washout period between treatments. Ipratropium bromide was allowed for symptomatic relief. The PD20 (dose of histamine causing a 20% fall in FEV1) was measured before and 11, 35, and 59 h after cessation of treatment and a bronchodilator dose-response study before and 83 h after cessation of treatment. Change from baseline after albuterol and broxaterol are compared with change after placebo. Diurnal change in PEF (amplitude % mean) increased during treatment with albuterol by 6.5% (95% CI, 1.7-12.3; p < 0.02) mainly because of a fall in morning PEF. Cessation of treatment with both beta 2-agonists was associated with a fall in FEV1 and PD20 compared with placebo.(ABSTRACT TRUNCATED AT 250 WORDS) During the 1970s, scientists suggested that the growing use of chlorofluorocarbons (CFCs) was contributing to depletion of the stratospheric ozone layer with potentially harmful results. A committee on the ozone layer organized the preparation of the Montreal Protocol. This protocol mandated the cessation of production and use of CFCs by January 1, 1996. The primary exemption to this ban is for the use of CFCs as propellants in metered dose inhalers (MDIs) for the treatment of asthma. Suitable replacement hydrofluoroalkane (HFA) propellants, such as HFA-134a, for use in MDIs have been identified. Albuterol, a selective beta-adrenergic agonist, currently widely available for inhalation asthma therapy, has been reformulated in HFA-134a (Proventil HFA). OBJECTIVE; To compare the efficacy of Proventil HFA to Ventolin, Proventil, and placebo (HFA-134a) MDI in protecting asthmatic patients from exercise-induced bronchoconstriction.
                This was a randomized, single-blind, placebo-controlled, 4-period crossover study of asthmatic patients with documented exercise-induced broncho-constriction. Twenty patients self administered two puffs of either Proventil HFA, Ventolin, Proventil or placebo, from an MDI, 30 minutes prior to performing a standardized exercise challenge at the study site. Spirometry was performed predose and 5, 10, 15, 30, 45, 60, 75, and 90 minutes after completion of the exercise challenge. Heart rate and blood pressure were measured just prior to spirometry and a 12-lead ECG was performed 15 minutes after completion of the exercise challenge for measurement of the QT corrected interval.
                The primary efficacy variable was the smallest percent change from the predose FEV1 following exercise. The smallest percent change from predose FEV1 for Proventil HFA was 2.0 +/- 9.9 SD, similar to the 2.0 +/- 11.4 SD for Ventolin, and the 3.6 +/- 10.2 SD for Proventil. The smallest percent change from predose FEV1 for each of the active treatments was significantly different from placebo, -23.7 +/- 14.5. Twelve of the patients had a > or = 20% fall in FEV1 post-exercise with placebo pretreatment, but only 1, 1, and 0 had > or = 20% FEV1 falls after treatment with Proventil HFA, Ventolin, and Proventil respectively. Changes in heart rate, blood pressure and QT corrected interval were similar for the three active treatments following exercise.
                Proventil HFA provides protection against exercise-induced bronchoconstriction comparable to Ventolin and Proventil and protection superior to placebo. Proventil HFA has a safety profile similar to Ventolin when used to prevent exercise-induced bronchoconstriction. Salmeterol xinafoate is an inhaled long-acting beta2-adrenoceptor agonist recently introduced for the treatment of asthma. Both in vitro and animal studies suggest that it may have anti-inflammatory activities of benefit in this disease. To assess this directly, the effects of 6 weeks' treatment with salmeterol on indices of clinical activity, airway dysfunction and inflammation in subjects with stable atopic asthma were investigated. In a double blind study, asthmatic patients were randomized to 6 weeks' treatment with either salmeterol 50 microg twice daily (n=14) or placebo (n=12). They underwent bronchoscopy with bronchoalveolar lavage (BAL) and bronchial biopsy immediately before starting treatment and again after 6 weeks. Treatment with salmeterol improved clinical indices of asthma activity, but there were no changes in BAL differential cell counts or mediator levels, and no change in T-cell numbers or activation status. In the biopsy specimens there were no changes in numbers of inflammatory cells, sub-basement membrane collagen deposition or mast cell degranulation. Regular treatment with salmeterol improves clinical indices of asthma but has no effect on the underlying inflammatory process. These findings strengthen guideline recommendations that long-acting beta2-agonists should not be prescribed as sole antiasthma medication. To determine whether initiation of maintenance treatment with the salmeterol (S)/fluticasone propionate (FP) combination (Seretide/Viani/Advair) is more effective than inhaled steroid alone in patients with asthma symptomatic on short-acting bronchodilator alone.
                150 asthma patients with symptoms and prn use of short-acting bronchodilator at least once a week were randomised to 24 weeks' treatment with either S/FP 50/100 microg bd (n = 78) or FP 100 microg bd (n = 72). The primary endpoint was the percentage of symptom-free 'day + night's.
                The percentage of symptom-free 'day + night's increased significantly more for S/FP (20 to 64%) compared to FP (24 to 51%). The treatment difference was 15.3%, P = 0.008. In the sub-group of patients with mild asthma the treatment difference was also statistically significant in favour of S/FP (P = 0.0245, n = 74). S/FP was also significantly superior to FP alone for: lung function, salbutamol use prn, day symptom score, symptom-free days, and episode-free 'day + night's. Treatments were equally well tolerated.
                Initial maintenance treatment with S/FP is significantly more effective than with inhaled steroid alone for patients symptomatic when treated with short-acting bronchodilator alone. This also apply to patients with mild persistent asthma. 1 Cardiovascular and airways response to two non-cardioselective beta-adrenoceptor blocking drugs, propranolol and pindolol (with partial agonist activity) and two cardioselective beta-adrenoceptor blocking drugs, acebutolol (with partial agonist activity) and atenolol, were compared in twelve patients with asthma. 2 All four drugs produced a significant reduction in resting pulse rate and prevented the increase in heart rate following inhaled isoprenaline (1,500 microgram). 3 Seven patients in clinical remission showed no significant bronchoconstrictor response to any of the drugs. In the remaining five patients, bronchoconstriction was greatest following propranolol (mean reduction in FEV1 26.6%) and least following atenolol (mean reduction in FEV1 6.5%). 4 The bronchodilator response to inhaled isoprenaline was blocked by propranolol and pindolol but not by acebutolol and atenolol. 5 Partial agonist activity did not appear to be clinically useful.
In a population of stable asthmatics short acting beta-agonists, mast cell stabilisers, or anticholinergics will provide a significant protective effect against exercise-induced bronchoconstriction with few adverse effects. On average, SABAs resulted in more effective attenuation than mast cell stabilisers, while mast cell stabilisers were more effective than anti-cholinergic agents. Combining SABA and mast cell stabilisers may be appropriate in selected cases. The variability in the individual degree of response to these drugs in multi arm trials suggests clinicians and patients work together to identify the most effective prophylactic therapy.