Efficacy and safety of once-daily umeclidinium/vilanterol 62.5/25 mcg in COPD.

STUDY OBJECTIVE: To examine the efficacy and safety of the once-daily, inhaled, long-acting muscarinic antagonist/ß2-agonist combination umeclidinium/vilanterol (UMEC/VI) compared with UMEC and VI monotherapies in patients with chronic obstructive pulmonary disease (COPD). METHODS: In this 24-week, double-blind, placebo-controlled, parallel-group study (ClinicalTrials.gov: NCT01313650) eligible patients were randomised 3:3:3:2 to treatment with UMEC/VI 62.5/25 mcg, UMEC 62.5 mcg, VI 25 mcg or placebo administered once daily via dry powder inhaler (N = 1532; intent-to-treat population). Primary endpoint was trough forced expiratory volume in one second (FEV1) on Day 169 (23-24 h post-dose). Additional lung-function, symptomatic, and health-related quality-of-life endpoints were assessed, including 0-6 h weighted-mean FEV1, rescue salbutamol use, Transition Dyspnoea Index (TDI), Shortness Of Breath With Daily Activity (SOBDA) and St. George's Respiratory Questionnaire (SGRQ) scores. Safety evaluations included adverse events (AEs), vital signs, 12-lead/24-h Holter electrocardiography parameters and clinical laboratory/haematology measurements. RESULTS: All active treatments produced statistically significant improvements in trough FEV1 compared with placebo on Day 169 (0.072-0.167 L, all p < 0.001); increases with UMEC/VI 62.5/25 mcg were significantly greater than monotherapies (0.052-0.095 L, p ≤ 0.004). Improvements were observed for UMEC/VI 62.5/25 mcg vs placebo for weighted-mean FEV1 on Day 168 (0.242 L, p < 0.001), rescue salbutamol use during Weeks 1-24 (-0.8 puffs/day, p = 0.001), TDI (1.2 units, p < 0.001), SOBDA (-0.17 units, p < 0.001) and SGRQ (-5.51 units, p < 0.001) scores. No clinically-significant changes in vital signs, electrocardiography, or laboratory parameters were observed. CONCLUSION: Once-daily UMEC/VI 62.5/25 mcg was well tolerated and provided clinically-significant improvements in lung function and symptoms in patients with COPD.

The bronchodilator response to salmeterol is maintained with regular, long-term use in patients with COPD.

Long-acting beta(2)-agonists (LABAs) are recommended in the management of patients with chronic obstructive pulmonary disease (COPD). Previous studies have demonstrated that the LABA, salmeterol, improves lung function, symptoms and quality of life in patients with COPD. In this study, we have performed additional analyses of the combined data from two previous double-blind, placebo-controlled, parallel studies of salmeterol (50 microg, b.i.d) in patients with COPD. The new analyses reveal that the significant improvements seen in pre-dose and 2-h post-dose forced expiratory volume in 1 s (FEV(1)) compared to placebo, occur early in the treatment period, and are sustained for at least 24 weeks. Moreover, improvements in peak expiratory flow rate occur as early as Day 1, and are sustained throughout the 24-week period. Additional analyses of 12-h FEV(1) data also show that salmeterol is associated with an increase in the area under the curve at Week 12 compared with Day 1, adding further support to evidence that it results in a sustained bronchodilator response, with no evidence of tolerance.

Cost-efficacy analysis of fluticasone propionate versus zafirlukast in patients with persistent asthma.

OBJECTIVE: To compare the relative value of an inhaled corticosteroid, fluticasone propionate 88 microg twice daily, versus an oral leukotriene receptor antagonist, zafirlukast 20 mg twice daily, in patients with persistent asthma currently receiving short acting beta2-agonists alone. STUDY DESIGN: A cost-efficacy analysis using resource utilisation and clinical data obtained prospectively from a multicentre, randomised, double-blind, double-dummy, placebo-controlled 12-week clinical trial conducted in the US. PERSPECTIVE: Third-party payor. PATIENTS AND METHODS: A total of 451 corticosteroid-naive patients with persistent asthma were treated with either fluticasone propionate 88 microg twice daily or zafirlukast 20 mg twice daily. All patients were given salbutamol (albuterol) to be used as rescue medication. Data were examined using intent-to-treat analysis. RESULTS: Mean daily per person cost-efficacy ratios using improvement in forced expiratory volume in 1 second (FEV1) [> or = 12% increase from baseline] were $US 3.47 for fluticasone propionate compared with $US 7.81 for zafirlukast (1999 values). The mean daily per person cost-efficacy ratios for symptom-free days obtained were $US 5.51 for fluticasone propionate compared with $US 14.98 for zafirlukast. These cost-efficacy ratios remained in favour of fluticasone propionate after a robust sensitivity analysis. CONCLUSIONS: Treatment with fluticasone propionate 88 kg twice daily was the most cost effective treatment compared with zafirlukast 20 mg twice daily in this 12-week clinical trial. This analysis supports the use of fluticasone propionate 88 microg twice daily as first-line treatment in patients with persistent asthma previously treated with short-acting beta2-agonist alone.

Comparison of fluticasone propionate-salmeterol combination therapy and montelukast in patients who are symptomatic on short-acting beta(2)-agonists alone.

The objective of this study was to determine whether initial maintenance therapy for the treatment of inflammation and bronchoconstriction associated with persistent asthma is more effective with a combination product (100 microg of fluticasone propionate and 50 microg of salmeterol [FSC]) administered twice daily through the Diskus device (GlaxoWellcome, Research Triangle Park, NC) or with montelukast at 10 mg once daily. A 12-wk, randomized, double-blind, double-dummy, multicenter study was conducted with 423 patients 15 yr of age and older with asthma and who were symptomatic while receiving short-acting beta(2)-agonists alone. At end point, FSC resulted in significantly greater increases in morning predose FEV(1) (0.54 +/- 0.03 vs. 0.27 +/- 0.03 L), morning peak expiratory flow (PEF) (89.9 +/- 6.7 vs. 34.2 +/- 4.7 L/min), evening PEF (69.9 +/- 5.8 vs. 31.1 +/- 4.5 L/min), the percentage of symptom-free days (48.9 +/- 2.9 vs. 21.7 +/- 2.5%), the percentage of rescue-free days (53.0 +/- 2.8 vs. 26.2 +/- 2.5%), and the percentage of nights with no awakenings (23.0 +/- 2.5 vs. 15.5+/-2.4%) compared with montelukast (p < or = 0.001, all comparisons). FSC significantly reduced asthma symptom scores (-1.0 +/- 0.1 vs. -0.6 +/- 0.1), rescue albuterol use (-3.3 +/- 0.2 vs. -1.9 +/- 0.2 puffs/d), and the number of exacerbations (0 vs. 11) compared with montelukast (p < 0.001). Both treatments were well tolerated. In summary, treatment of the two main components of asthma (inflammation and bronchoconstriction) with fluticasone propionate and salmeterol in a combination product was a more effective initial maintenance treatment strategy than treatment with montelukast, a single-mediator antagonist.

Comparison of inhaled salmeterol and oral zafirlukast in asthmatic patients using concomitant inhaled corticosteroids.

CONTEXT: For asthmatic patients who remain symptomatic on inhaled corticosteroids, augmenting the therapy with additional long-term control medication is advocated. Long-acting beta2-adrenergic agonists and leukotriene modifiers are 2 therapeutic alternatives in the long-term controller class. OBJECTIVE: To compare the addition of a long-acting beta2-adrenergic agonist to the addition of an oral leukotriene modifier for asthma therapy in patients who remain symptomatic on inhaled corticosteroids. DESIGN: Double-blind, double-dummy, parallel-group, multicenter clinical studies. SETTING: 54 outpatient clinical centers. PATIENTS: 429 male and female patients with asthma 12 years of age and older who were symptomatic while taking inhaled corticosteroids. INTERVENTIONS: Salmeterol xinafoate 42 mcg via metered dose inhaler twice daily or oral zafirlukast 20 mg twice daily. MAIN OUTCOME MEASURES: Pulmonary function, asthma symptoms, supplemental albuterol use, asthma quality of life scores, and adverse events. RESULTS: Inhaled salmeterol provided significantly greater improvement in pulmonary function as well as significantly greater relief of both daytime and nighttime asthma symptoms compared with oral zafirlukast in patients concurrently treated with inhaled corticosteroids. The use of supplemental albuterol was reduced to a greater extent with salmeterol compared with zafirlukast. Patients treated with salmeterol showed significantly greater improvement in Asthma Quality of Life Questionnaire (AQLQ) scores and were satisfied with how fast, how long, and how well the medication worked compared with patients in the zafirlukast group. Both treatments were well tolerated and demonstrated similar safety profiles. CONCLUSIONS: In patients with moderate to severe persistent asthma not sufficiently controlled with inhaled corticosteroids alone, the combination of inhaled salmeterol and inhaled corticosteroids is superior to the combination of oral zafirlukast and inhaled corticosteroids as stepwise therapy.

A comparison of short-term treatment with inhaled fluticasone propionate and zafirlukast for patients with persistent asthma.

PURPOSE: To compare the short-term efficacy and safety of low-dose fluticasone propionate with that of oral zafirlukast therapy for patients previously treated with beta-2-agonists alone, and to evaluate the potential therapeutic benefit of switching from zafirlukast to a low-dose inhaled corticosteroid. SUBJECTS AND METHODS: This study consisted of a 4-week randomized, double-blind treatment period followed by a 4-week open-label period. Two hundred ninety-four patients > or =12 years old with asthma previously uncontrolled with beta-2-agonists alone were randomly assigned to treatment with low-dose inhaled fluticasone (88 microg twice daily) or oral zafirlukast (20 mg twice daily). After 4 weeks, all patients discontinued their double-blind therapy and received open-label fluticasone (88 microg twice daily). Outcomes included pulmonary function, asthma symptoms, albuterol use, asthma exacerbations, and adverse events. RESULTS: During the double-blind treatment period, fluticasone patients had significantly greater improvements in morning peak flow (29.3 L/min vs. 18.3 L/min), percentage of symptom-free days (19.8% vs. 11.6%), and daily albuterol use (-1.8 puffs per day vs. -1.1 puffs per day) compared with zafirlukast patients (P < or =0.025, each comparison). During the open-label treatment period, patients switched from zafirlukast to fluticasone experienced additional improvements in morning peak flow (17.2 L/min), evening peak flow (13.6 L/min), and FEV(1) (0.11 liter) and daily albuterol use (-0.9 puffs daily) compared with values obtained at the end of the double-blind treatment period (P < or =0.001, each comparison). CONCLUSION: Low-dose fluticasone was more effective than zafirlukast in improving pulmonary function and symptoms in patients with persistent asthma. In addition, switching patients from zafirlukast to fluticasone further improved clinical outcomes.

Addition of salmeterol to low-dose fluticasone versus higher-dose fluticasone: an analysis of asthma exacerbations.

BACKGROUND: Adding salmeterol to low-dose fluticasone propionate (FP) produces greater improvements in pulmonary function and symptom control than increasing the dose of FP in patients who remain symptomatic with low-dose FP. OBJECTIVE: We sought to compare the rates and characteristics of asthma exacerbations in patients after adding salmeterol to low-dose FP with the rates and characteristics of exacerbations in patients receiving higher dose FP. METHODS: In 2 multicenter, double-blind studies, 925 patients 12 years of age and older receiving 88 microg twice daily FP randomly received either 42 microg of salmeterol and 88 microg of FP or an increased dose of FP (220 microg) twice daily for 24 weeks. Exacerbation rates and clinical measures of asthma worsening were assessed for all patients who experienced an asthma exacerbation. RESULTS: The addition of salmeterol resulted in a significantly lower rate and number of exacerbations compared with higher dose FP. A total of 41 (8.8%) patients experienced 47 exacerbations with the addition of salmeterol compared with 63 (13.8%) patients with 75 exacerbations in the group receiving increased-dose FP (P =.017). Salmeterol plus low-dose FP was significantly more protective than increased-dose FP in preventing asthma exacerbations, as assessed by the time to first exacerbation (P <.05). In both groups clinical indicators of worsening asthma showed parallel changes before asthma exacerbation, and greater improvements were observed after exacerbation with salmeterol compared with higher dose FP. CONCLUSION: Salmeterol plus low-dose FP was more effective than higher dose FP alone in reducing asthma exacerbations in patients with persistent asthma. The ability to detect deteriorating asthma and the severity of exacerbation was similar between groups.

Low-dose fluticasone propionate compared with montelukast for first-line treatment of persistent asthma: a randomized clinical trial.

BACKGROUND: Both inhaled corticosteroids and leukotriene modifiers are used in the maintenance treatment of persistent asthma. OBJECTIVE: The goal was to compare the efficacy and safety of low-dose fluticasone propionate (FP) and montelukast as first-line maintenance therapy in symptomatic patients by using short-acting beta2-agonists alone to treat persistent asthma. METHODS: In this multicenter, randomized, double-blind, double-dummy, parallel-group study, 533 patients (>15 years old) with persistent asthma who remained symptomatic while taking short-acting beta2-agonists alone were treated with FP (88 microg [2 puffs of 44 microg] twice daily) or montelukast (10 mg once daily) for 24 weeks. RESULTS: Compared with treatment with montelukast, treatment with FP resulted in significantly greater improvements at endpoint in morning predose FEV(1) (22.9% vs 14.5%, P <.001), forced midexpiratory flow (0.66 vs 0.41 L/sec, P <.001), forced vital capacity (0.42 vs 0.29 L, P =.002), morning peak expiratory flow (PEF) (68.5 vs 34.1 L/min, P <.001), and evening PEF (53.9 vs 28.7 L/min, P <.001). Similar improvements in PEF were observed in patients with milder asthma (>70%-80% predicted FEV(1)). At endpoint, FP was more effective than montelukast at decreasing rescue albuterol use (3.1 puffs/day vs 2.3 puffs/day, P <.001), asthma symptom scores (-0.85 [48.6% decrease] vs -0.60 [30.5%], P <.001), and nighttime awakenings due to asthma (-0.64 awakenings/night [62% decrease] vs -0.48 awakenings/night [47.5%], P =.023), and FP increased the percentage of symptom-free days (32.0% vs 18.4% of days, P <.001) compared with montelukast. The adverse event and asthma exacerbation profiles for FP and montelukast were similar. CONCLUSIONS: Low-dose FP is more effective than montelukast as first-line maintenance therapy for patients with persistent asthma who are undertreated and remain symptomatic while taking short-acting beta2-agonists alone.

Low-dose inhaled fluticasone propionate versus oral zafirlukast in the treatment of persistent asthma.

BACKGROUND: Few studies have compared the efficacy of inhaled corticosteroids and leukotriene modifiers for the treatment of persistent asthma. OBJECTIVE: Our purpose was to compare the efficacy of a low dose of inhaled fluticasone propionate (FP) with that of oral zafirlukast in the treatment of persistent asthma previously treated with short-acting beta(2)-agonists alone. METHODS: A 12-week, randomized, double-blind, double-dummy, multicenter study was conducted in 451 patients aged 12 years and older with asthma who were symptomatic on short-acting beta(2)-agonists alone. After an 8- to 14-day run-in period, patients were randomized to treatment with FP 88 microg twice daily or zafirlukast 20 mg twice daily. RESULTS: Treatment with FP was more effective than treatment with zafirlukast in increasing morning FEV(1) (by 0.42 L vs 0.20 L over baseline, P <.001), morning peak expiratory flow (by 49.94 L/min vs 11.68 L/min over baseline, P <. 001), and evening PEF (by 38.91 L/min vs 10.50 L/min over baseline, P <.001). Statistically significant differences between the two treatments in FEV(1) were noted after the first observation (week 4) and in morning and evening peak expiratory flow by week 2. Mean change in percentage of symptom-free days was greater with FP than with zafirlukast (28.5% of days vs 15.6% of days, P <.001) and FP significantly increased the percentage of rescue-free days by 40.4% of days compared with 24.2% of days with zafirlukast (P <.001). Treatment with FP significantly reduced albuterol use by 2.39 puffs per day compared with 1.45 puffs per day (P <.001) and increased the percentage of nights with no awakenings by 21.2% of nights compared with 8.0% of nights with zafirlukast (P <.001). CONCLUSION: The clinical effectiveness of a low dose of FP as first-line therapy in patients with persistent asthma who are symptomatic on beta(2)-agonists alone is superior to that of zafirlukast.

Effect of long-term salmeterol therapy compared with as-needed albuterol use on airway hyperresponsiveness.

STUDY OBJECTIVES: To determine the effect of long-term salmeterol aerosol therapy on airway hyperresponsiveness measured by methacholine challenge. DESIGN: Randomized, double-blind, placebo-controlled, multicenter study. SETTING: Thirty-one clinical centers in the United States. PATIENTS: Four hundred eight asthmatic patients > or = 12 years of age with baseline FEV1 of > or = 70% of predicted values. Patients were not using inhaled corticosteroids. INTERVENTIONS: Twice-daily salmeterol aerosol, 42 microg, or placebo via metered-dose inhaler for 24 weeks. Backup albuterol was available. MEASUREMENTS AND RESULTS: Pulmonary function tests were performed before, during, and after treatment. Subjects recorded asthma-related symptoms, morning and evening peak expiratory flow (PEF) levels, and use of supplemental albuterol daily on diary cards. Methacholine challenges were performed 10 to 14 h postdose at weeks 4, 12, and 24, and 3 and 7 days posttreatment. Over 24 weeks of treatment, salmeterol provided significant (p < 0.001) protection against methacholine-induced bronchoconstriction of approximately one doubling dose of methacholine when compared to placebo with no evidence for a progressive decrease in protection. A rebound increase in airway hyperresponsiveness was not observed 3 and 7 days after cessation of salmeterol therapy. Salmeterol treatment resulted in sustained improvements of 0.21 to 0.26 L in morning premedication FEV1 and an improvement of 26.2 L/min in morning PEF when compared to placebo (p < 0.001). The use of salmeterol significantly reduced combined daytime asthma symptoms by 20% when compared to placebo (p = 0.005). A total of 34 and 48 exacerbations, respectively, were reported in the Salmeterol and placebo groups, and no evidence was present for a difference in the severity of asthma exacerbations between groups. Adverse event profiles were similar for the salmeterol and placebo groups. CONCLUSIONS: Regular long-term use of salmeterol aerosol resulted in sustained improvements in pulmonary function and asthma symptom control over the 24-week treatment period. There was no increase in bronchial hyperresponsiveness or loss of bronchoprotection at 24 weeks from that seen following 4 weeks of therapy. There was no evidence of rebound airway hyperresponsiveness after cessation of salmeterol treatment. Regular treatment with the long-acting beta-agonist salmeterol does not lead to clinical instability or vulnerability to unpredictable asthma attacks.

Comparison of inhaled salmeterol and oral zafirlukast in patients with asthma.

BACKGROUND: Salmeterol, a long-acting beta2 -agonist, and zafirlukast, a leukotriene receptor antagonist, are both indicated for the treatment of asthma in adolescent and adult patients. OBJECTIVE: We sought to compare the effect of 4 weeks of treatment with inhaled salmeterol xinafoate versus oral zafirlukast in the treatment of persistent asthma. METHODS: This was a randomized, double-blind, double-dummy, parallel-group, multicenter clinical trial. Patients, over 80% of whom were on a concurrent inhaled corticosteroid regimen, were treated for 4 weeks with either inhaled salmeterol xinafoate 42 microgram twice daily administered by means of a metered-dose inhaler or oral zafirlukast 20 mg twice daily. The primary efficacy measure was morning peak expiratory flow (PEF); secondary efficacy measures included evening PEF, asthma symptom scores, supplemental albuterol use, nighttime awakenings, sleep symptoms, asthma exacerbations, and FEV1. RESULTS: Both inhaled salmeterol and oral zafirlukast resulted in within-group improvements from baseline in measures of pulmonary function, asthma symptoms, and supplemental albuterol use. Salmeterol treatment resulted in significantly greater improvements from baseline compared with zafirlukast for most efficacy measurements, including morning PEF (29.6 vs 13.0 L/min; P

The addition of salmeterol to fluticasone propionate versus increasing the dose of fluticasone propionate in patients with persistent asthma. Salmeterol Study Group.

BACKGROUND: Current treatment guidelines define inhaled corticosteroids such as fluticasone propionate (FP) as the cornerstone of anti-inflammatory therapy for asthma. OBJECTIVE: The objective was to evaluate the efficacy and safety of adding salmeterol therapy to patients who remain symptomatic while receiving FP as compared with increasing the dose of FP. METHODS: In a multicenter, double-blind study conducted over 24-weeks, 437 patients aged 12 years and older and receiving FP 88 microg twice daily for 2 to 4 weeks were randomly assigned to receive either salmeterol (42 microg twice daily) or FP 220 microg twice daily. The primary efficacy endpoint was morning peak expiratory flow. Secondary measures included FEV1, symptom scores, nighttime awakenings, and supplemental albuterol use. Safety was assessed by reported adverse events and asthma exacerbations. RESULTS: The addition of salmeterol resulted in significantly greater improvements in lung function and symptom control as compared with increasing the dose of FP. Over weeks 1 to 24, morning peak expiratory flow was increased by 47 L/min from baseline with salmeterol treatment as compared with 24 L/min with FP 220 microg twice daily (P < .001) while the percent of symptom-free days increased from baseline by 26% of days as compared with 10% of days (P < .001). The adverse event profiles were similar between groups and fewer exacerbations were reported with salmeterol treatment. CONCLUSIONS: The addition of salmeterol therapy to patients who remain symptomatic while using a low dose of FP was clinically and statistically superior to increasing the dose of FP.

Efficacy, safety, and effects on quality of life of salmeterol versus albuterol in patients with mild to moderate persistent asthma.

BACKGROUND: Salmeterol xinafoate is a long-acting, highly selective, beta2-adrenergic agonist that produces bronchodilation and clinically significant improvement in pulmonary function for up to 12 hours in patients with asthma. OBJECTIVE: To evaluate the impact on asthma-specific quality of life, efficacy, and safety of salmeterol versus albuterol in adult patients with mild-to-moderate persistent asthma. METHODS: A randomized, double-blind, double-dummy, parallel-group, multicenter study was conducted in 539 adult asthma patients over 12 weeks. Patients were randomized to receive either salmeterol 42 microg via metered-dose inhaler twice daily or albuterol 180 microg four times daily. Upon entry into the study, 46% of patients were being treated with an inhaled corticosteroid and were allowed to continue treatment throughout the study. Pulmonary function and asthma symptoms were monitored daily, and patients completed the Asthma Quality of Life Questionnaire (AQLQ) at baseline and after 4, 8, and 12 weeks of treatment. RESULTS: Treatment with salmeterol twice daily produced significantly greater improvements from baseline in all quality of life domain ("Activity Limitation," "Asthma Symptoms," "Emotional Function," "Environmental Exposure") scores and in the global AQLQ score at 12 weeks (P < or = .038) compared with albuterol treatment four times daily. Pulmonary function and asthma symptoms were also significantly improved with salmeterol compared with albuterol. CONCLUSIONS: Salmeterol 42 microg administered twice daily is significantly more effective than albuterol 180 microg four times daily for improving asthma-specific quality of life, controlling asthma symptoms, and improving pulmonary function in patients with mild-to-moderate persistent asthma. Furthermore, those improvements were maintained over a 12-week period.

Salmeterol improves quality of life in patients with asthma requiring inhaled corticosteroids. Salmeterol Quality of Life Study Group.

BACKGROUND: Traditional clinical outcomes have demonstrated that salmeterol improves pulmonary function and reduces asthma symptoms. However, they do not evaluate how patients perceive the effect of therapeutic intervention on day-to-day functioning and well-being. OBJECTIVE: We sought to evaluate the impact of salmeterol on disease-specific quality of life with the Asthma Quality-of-Life Questionnaire, as well as the efficacy and safety of salmeterol in patients with stable asthma who were symptomatic despite daily use of inhaled corticosteroids. METHODS: This was a randomized, double-blind, placebo-controlled, parallel-group study of 506 patients. Patients were treated with 42 microg salmeterol or placebo twice daily for 12 weeks delivered through a metered dose inhaler. RESULTS: Mean change from baseline in asthma quality-of-life scores was significantly greater (p < or = 0.006) after 12 weeks of treatment with salmeterol compared with placebo ("as-needed" albuterol) in global scores (1.08 vs 0.61) and individual domains (activity limitations, 0.91 vs 0.54; asthma symptoms, 1.28 vs 0.71; emotional function, 1.17 vs 0.65; and environmental exposure, 0.84 vs 0.47). Patients treated with salmeterol experienced significantly greater improvements from baseline to week 12 compared with placebo in FEV1 (0.42 L vs 0.15 L, p < 0.001), morning peak expiratory flow (47 L/min vs 14 L/min, p < 0.001), evening peak expiratory flow (29 L/min vs 11 L/min, p < 0.001), and asthma symptom scores (daytime scores reduced by 0.55 vs 0.30, p < 0.001). Patients treated with salmeterol used significantly less supplemental albuterol (reduced by 3 puffs/day vs 1 puff/day, p < 0.001). CONCLUSION: Salmeterol provided significantly greater improvement in quality-of-life outcomes in patients whose asthma symptoms are not well controlled with inhaled corticosteroids. These results demonstrate that the benefits of salmeterol are not limited to conventional clinical measures of efficacy.

The cholinergic stimulating effects of ciliary neurotrophic factor and leukemia inhibitory factor are mediated by protein kinase C.

The intracellular mechanisms through which two trophic factors, ciliary neurotrophic factor (CNTF) and leukemia inhibitory factor (LIF), regulate cholinergic development were examined in sympathetic neuron cultures. Treatment with CNTF or LIF increased levels of choline acetyltransferase (ChAT) activity by 375 and 350%, respectively. However, in neuronal cultures depleted of protein kinase C (PKC) activity by chronic phorbol ester treatment, neither CNTF nor LIF elevated ChAT activity. Further, the stimulation of ChAT due to increased cell density was not observed in PKC-depleted sympathetic neurons. The inhibition of CNTF-stimulated ChAT by phorbol ester occurred in a dose-dependent manner and chronic phorbol ester treatments did not alter the levels of the catecholamine biosynthetic enzyme tyrosine hydroxylase. Moreover, increased levels of diacylglycerol, an endogenous activator of PKC, were observed in sympathetic neurons treated with CNTF. However, neither CNTF nor LIF stimulated the hydrolysis of phosphatidylinositol 4,5-bisphosphate. These observations suggest that a common PKC-dependent pathway, which is independent of phosphatidylinositol 4,5-bisphosphate hydrolysis, mediates the cholinergic stimulating effects of CNTF, LIF, and cell-cell contact in cultured sympathetic neurons.

Regulation of angiotensin II binding sites in neuronal cultures by protein kinase C.

The radioligand binding of 125I-angiotensin II (ANG II) and calcium phospholipid-dependent protein kinase C (PKC) activity were measured to study the specificity and mechanisms of PKC involvement in the regulation of ANG II-specific binding site expression in neuronal cultures prepared from the brains of 1-day-old rats. Previously, PKC-activating phorbol esters were shown to increase the specific binding of 125I-ANG II in neuronal cultures. However, phorbol esters have many biological effects, which may nonspecifically act to increase 125I-ANG II-specific binding. In the present study, mezerein and teleocidin A, two activators of PKC that are chemically unrelated to phorbol esters, increased the specific binding of 125I-ANG II in a dose- and time-dependent manner with 50% effective dose (ED50) values of 32 and 79 nM, respectively. The PKC antagonist H-7 dose dependently inhibited phorbol 12-myristate 13-acetate (TPA)-stimulated increases in 125I-ANG II binding, whereas downregulation of PKC activity by chronic phorbol ester incubations of 24 and 48 h prevented TPA-stimulated increases in 125I-ANG II-specific binding. TPA (0.8 microM), mezerein (0.76 microM), and teleocidin A (0.5 microM) all caused a rapid translocation of PKC activity from the cytosol to the particulate fraction by 15 min. Temporally, the maximal stimulation of PKC translocation by mezerein, teleocidin A, and TPA preceded their ability to stimulate maximal 125I-ANG II-specific binding. Taken together, these results suggest that PKC is directly involved in the stimulation of ANG II-specific binding site expression and that translocation of PKC is a prerequisite for the increased expression of ANG II binding sites.

Adrenergic and calcium-mediated subcellular redistribution of protein kinase C in primary neuronal cultures.

Incubation of primary neuronal cultures prepared from the brains of neonatal rats with 50 microM epinephrine resulted in the transient redistribution of protein kinase C from the cytosol to the particulate fraction. This effect occurred after 1 and 5 min of incubation and resulted in a decrease in cytosolic protein kinase C activity with a corresponding increase in particulate protein kinase C of approximately 30% and 15%, respectively. The epinephrine-stimulated translocation of protein kinase C was blocked by 1 microM prazosin indicating the involvement of alpha 1-adrenergic receptors. Further, inclusion of 0.1 microM Ca2+ in the homogenization buffer was found to significantly enhance the binding of protein kinase C to cellular membranes prepared from neuronal cultures. These results indicate that alpha 1-adrenergic receptors in neuronal brain cell cultures are linked to the activation of protein kinase C and that the mobilization of Ca2+ may enhance this effect.

Phorbol ester-induced upregulation of angiotensin II receptors in neuronal cultures is potentiated by a calcium ionophore.

Previous studies have suggested that protein kinase C is important in the regulation of angiotensin II receptors in neuronal cultures, because the C-kinase agonists, phorbol esters, are able to increase the number of these receptors. In the present study, we have further investigated the role of protein kinase C in angiotensin II receptor regulation. This enzyme is calcium dependent, and so we investigated the effects of A23187, a calcium ionophore, on phorbol ester-stimulated and basal angiotensin II receptor regulation. A23187, at concentrations that increased 45Ca2+ influx, caused a dose-dependent potentiation of phorbol-12-myristate-13-acetate (TPA)-stimulated upregulation of angiotensin II receptors. This potentiation by A23187 was a further increase in angiotensin II receptor number and was abolished in calcium-free medium. In the absence of TPA, A23187 caused a decrease in angiotensin II receptor number, an effect not observed in calcium-free medium. The results suggest at least two pathways for angiotensin II receptor regulation in neuronal cells: (a) by calcium-dependent protein kinase C and (b) via an influx of calcium into the cell.