Inhaled salmeterol/fluticasone propionate combination: a review of its use in persistent asthma

Comparisons between In-Check DIAL® and PF810® in evaluation and training inspiratory capacity for using dry powder inhalers

BACKGROUND

Dry powder inhalers (DPIs) rely on both internal resistance and patients' inspiratory capacity for effective operation. Optimal inspiratory technique is crucial for DPI users. This study assessed the accuracy and repeatability of two available devices, PF810® and In-Check DIAL®, and analyzed their measurement errors and consistency in detecting inspiratory capacity.

METHODS

The accuracy and repeatability of peak inspiratory flow (PIF) and forced inspiratory vital capacity (FIVC) against various internal resistances of the two devices were assessed using standard waveforms generated by a breathing simulator. The agreement of PIF measurements between the two devices in healthy volunteers and chronic obstructive pulmonary disease (COPD) patients was analyzed with the intraclass correlation coefficient and Bland-Altman graphical analysis.

RESULTS

PF810® showed great accuracy and repeatability in measuring PIF, except for square waveforms at the lowest flow rate (20 L/min). In-Check DIAL® exhibited poor accuracy against high resistance levels. In scenarios with no resistance, In-Check DIAL® had significantly smaller measurement errors than PF810®, but larger errors against high resistance levels. The two devices showed excellent agreement (ICC > 0.80, P < 0.05), except for healthy volunteers against medium to high resistance (R3-R5) where the ICC was insignificant. Bland-Altman plots indicated small disagreements between the two devices for both healthy volunteers and COPD patients.

CONCLUSIONS

In-Check DIAL® exhibited poor accuracy and larger measurement errors than PF810® when detecting PIFs against higher internal resistances. However, its good performance against lower internal resistances, along with its cost-effectiveness and convenience made it appropriate for primary care. PF810® showed good accuracy and repeatability and could detect additional parameters of inspiratory capacity beyond PIF, though required further studies to confirm its clinical benefits.

Microencapsulation of Fluticasone Propionate and Salmeterol Xinafoate in Modified Chitosan Microparticles for Release Optimization

Chitosan (CS) is a natural polysaccharide, widely studied in the past due to its unique properties such as biocompatibility, biodegradability and non-toxicity. Chemical modification of CS is an effective pathway to prepare new matrices with additional functional groups and improved properties, such as increment of hydrophilicity and swelling rate, for drug delivery purposes. In the present study, four derivatives of CS with trans-aconitic acid (t-Acon), succinic anhydride (Succ), 2-hydroxyethyl acrylate (2-HEA) and acrylic acid (AA) were prepared, and their successful grafting was confirmed by FTIR and ¹H-NMR spectroscopies. Neat chitosan and its grafted derivatives were fabricated for the encapsulation of fluticasone propionate (FLU) and salmeterol xinafoate (SX) drugs, used for chronic obstructive pulmonary disease (COPD), via the ionotropic gelation technique. Scanning electron microscopy (SEM) micrographs demonstrated that round-shaped microparticles (MPs) were effectively prepared with average sizes ranging between 0.4 and 2.2 μm, as were measured by dynamic light scattering (DLS), while zeta potential verified in all cases their positive charged surface. FTIR spectroscopy showed that some interactions take place between the drugs and the polymeric matrices, while X-ray diffraction (XRD) patterns exhibited that both drugs were encapsulated in MPs’ interior with a lower degree of crystallinity than the neat drugs. In vitro release studies of FLU and SX exposed a great amelioration in the drugs’ dissolution profile from all modified CS’s MPs, in comparison to those of neat drugs. The latter fact is attributed to the reduction in crystallinity of the active substances in the MPs’ interior.

Budesonide/salmeterol in fixed-dose combination for the treatment of asthma

Fixed dose combinations (FDC) of inhaled corticosteroid (ICS) and long-acting beta agonist (LABA) are well established in asthma treatment. The budesonide/salmeterol (B/S) FDC is now about to reach the market. It is provided as powder in hard capsules of two strengths: 120/20μg and 240/20μg when expressed as delivered doses, equivalent to 150/25μg and 300/25μg when expressed as nominal doses. Its development involved 9 pharmacokinetic (320 subjects), 3 phase II (123 subjects) and 4 phase III (1206 patients with different asthma severity) studies. Delivery is effectuated via low resistance inhaler device, Axahaler®, generating also fine particles targeting the small airways. B/S safety, assessed in 1401 subjects, did not outline novel concerns specific for this FDC. In conclusion, the B/S dry powder FDC can be used for asthma treatment in adults not adequately controlled on ICS alone, or to maintain control of ICS/LABA treated patients, in whom switching to alternative FDC is indicated.

Efficacy and Safety of Salmeterol/Fluticasone Propionate Combination Delivered by the Diskustrade mark or Pressurised Metered-Dose Inhaler in Children with Asthma

BACKGROUND AND OBJECTIVE

Salmeterol and fluticasone propionate are well established in the treatment of childhood asthma, and their combination is effective in children aged 4-11 years. Asthma guidelines recommend that the inhaler device best suited to the individual should be used to administer asthma treatment. The aim of this study was to further evaluate the efficacy of salmeterol/fluticasone propionate combination (SFC) delivered by the Diskustrade mark (50/100mug, one inhalation twice daily) and compare it with that observed when SFC is delivered by a chlorofluorocarbon-free pressurised metered-dose inhaler (pMDI) [25/50mug, two inhalations twice daily] in children aged 4-11 years with persistent asthma.

PATIENTS AND METHODS

This equivalence study had a multicentre, randomised, double-blind, double-dummy, parallel-group design and comprised asthmatic children aged 4-11 years who required beclometasone (beclomethasone dipropionate) </=500 mug/day (or equivalent). After a 2-week run-in using existing inhaled corticosteroid therapy, patients were randomised to receive SFC via Diskustrade mark (n = 213) or pMDI (n = 215, with 82% using a spacer) for 12 weeks. Salbutamol (Ventolin((R))) was provided for symptomatic relief. The primary endpoint was mean morning peak expiratory flow rate (PEF) recorded by patients during weeks 1-12. Secondary endpoints included other lung function parameters, day- and night-time symptoms, use of rescue medication and percentage of symptom- and salbutamol-free days. Adverse events and 12-hour overnight urinary cortisol concentrations were monitored to assess safety.

RESULTS

Treatment with SFC, delivered by either device, was highly effective in improving patients' morning PEF and asthma symptoms. Over the whole study period, morning PEF (mean +/- standard error) improved by 37.7 +/- 3.1 L/min in the Diskustrade mark group and by 38.6 +/- 3.0 L/min in the pMDI group. The -0.9 L/min difference between groups (95% CI -7.1, 5.4) was within the predefined criterion for equivalence of (i.e. -15, 15 L/min). The median percentage of symptom-free and rescue medication-free days and nights increased considerably in both groups. For all efficacy parameters assessed, improvement occurred for all age groups as early as weeks 1-4, and was sustained over the 12 weeks. Both Diskustrade mark and pMDI treatments were well tolerated and their safety profiles were comparable.

CONCLUSION

SFC delivered via Diskustrade mark or pMDI was shown to be highly effective in asthmatic children aged 4-11 years. Children as young as 4 years were able to use the Diskustrade mark and pMDI effectively. The combination is clinically equivalent when administered via either device in this patient population. This means that both Diskustrade mark and pMDI (+ spacer) are suitable for administration of SFC, which provides prescribers/users with a choice of device.

Inhaled Salmeterol/Fluticasone Propionate Combination in Chronic Obstructive Pulmonary Disease

Salmeterol/fluticasone propionate is a fixed-dose combination of the long-acting beta2-adrenoceptor agonist salmeterol and the corticosteroid fluticasone propionate and is inhaled via the Diskus powder inhaler. In three randomized, double-blind, 24-week or 52-week studies in >2850 patients with chronic obstructive pulmonary disease (COPD), administration of salmeterol/fluticasone propionate 50/250 microg twice daily (in one study) and salmeterol/fluticasone propionate 50/500 microg twice daily (in the other studies) provided greater improvement in lung function than placebo or either component alone at the same nominal dosage. Both strengths of the combination product administered twice daily resulted in clinically meaningful increases in scores in health-related quality-of-life questionnaires that were specific for respiratory disease. Improvements in this and almost all other secondary measures of efficacy, including symptomatic outcomes, were significantly greater with the combination product than with placebo. Administration of salmeterol/fluticasone propionate as a combination product did not result in any untoward interactions that affected the pharmacodynamic, pharmacokinetic or tolerability profiles of the individual components. Candidiasis, hoarseness/dysphonia, throat irritation and headache occurred more frequently with salmeterol/fluticasone propionate than with placebo in patients with COPD.

Phytoceuticals: the new 'physic garden' for asthma and chronic obstructive pulmonary disease

Phytoceuticals (non-nutritional but beneficial plant chemicals) merit investigation as pharmacotherapy for asthma and chronic obstructive pulmonary disease (COPD). Although asthma is mostly treated adequately, COPD is not. Thus, there is a need for new drugs with improved therapeutic benefit, especially in COPD. Recent interest in herbal remedies has redirected attention towards plants as sources of improved treatments for lung disease. Phytoceuticals from a variety of plants and plant products, including butterbur, English ivy, apples, chocolate, green tea and red wine, demonstrate broad-spectrum pharmacotherapeutic activities that could be exploited in the clinic. Well-designed clinical trials are required to determine whether these beneficial activities are reproduced in patients, with the prospect that phytoceuticals are the new physic garden for asthma and COPD.

Budesonide/formoterol dry powder in asthma: an option for control as maintenance and reliever therapy

IMPORTANCE OF THE FIELD

Asthma is a heterogeneous disease with various components that may contribute to symptoms. Obtaining global control of is one of the fundamental parts of the management of this disease.

AREAS COVERED IN THIS REVIEW

The Cochrane trial database, Medline and Embase, were searched systematically, and approximately 20 respiratory journals and conference abstracts were searched manually. The search was limited to publications in English language of last 20 years and which included the keywords 'budesonide', 'formoterol', 'asthma' and 'control'.

WHAT THE READER WILL GAIN

The purposes of this review are: i) to discuss the rationale about possibility of using combination therapy administered with a single inhaler for both daily maintenance and relief as needed of breakthrough symptoms in asthma management; ii) to give readers the current status of clinical pharmacological treatment of asthma; iii) to discuss the evidence on the use of budesonide/formoterol dry powder in one inhaler.

TAKE HOME MESSAGE

Among the various inhalatory drugs, budesonide and formoterol can be conveniently delivered in one dry powder inhaler and simplify treatment by providing immediate step-up when symptoms increase. Alongside the anti-inflammatory component, formoterol provides both short- and long-acting bronchodilator effects with maintenance and reliever properties. The option of using one inhaler simplifies treatment by simultaneously providing bronchodilator and anti-inflammatory activity, thus enhancing compliance. As indicated in guidelines, all these characteristics are essential for optimizing asthma treatment and control.

Inhaled fluticasone propionate reduces postoperative sore throat, cough, and hoarseness

BACKGROUND

Sore throat is a common complication after surgery. Postoperative cough and hoarseness can also be distressing to patients. We sought to determine the effect of an inhaler steroid on sore throat, cough, and hoarseness during the first 24 hours of the postoperative period.

METHODS

We enrolled 120 women with ASA physical status I or II and term singleton pregnancy who were scheduled for elective cesarean delivery under general anesthesia. Patients were randomized into 2 groups: in the sitting position, group F patients received 500 μg inhaled fluticasone propionate via a spacer device during 2 deep inspirations, after arrival in the operating room, and group C had no treatment. The patients were interviewed by a blinded investigator for postoperative sore throat, cough, and hoarseness at 1 and 24 hours after surgery.

RESULTS

There were no significant differences in age, height, weight, body mass index, duration of surgery, intubation, and grade of laryngeal exposure between the 2 groups. The incidence of sore throat, cough, and hoarseness was significantly lower in group F (3.33%, 3.33%, and 3.33%) compared with the control group (36.67%, 18.33%, and 35%) (P < 0.05 for all comparisons), not only in the first postoperative hour but also 24 hours after surgery (13.33%, 13.33%, and 25% in group F vs 40%, 41.67%, and 50% in the control group). The incidence of moderate and severe hoarseness in group F at the first hour was significantly less than the control group (P < 0.05).

CONCLUSIONS

Inhaled fluticasone propionate decreases the incidence and severity of postoperative sore throat, cough, and hoarseness in patients undergoing cesarean delivery under general anesthesia.

The effect of budesonide and formoterol in one pressurized metered-dose inhaler on patient-reported outcomes in adults with mild-to-moderate persistent asthma

OBJECTIVE

To determine the effects of budesonide and formoterol administered via one pressurized metered-dose inhaler (budesonide/formoterol pMDI) on patient-reported outcomes (PROs) and to determine the contributions of budesonide and formoterol to those effects in adults with asthma.

RESEARCH DESIGN AND METHODS

A 12-week, randomized, double-blind, double-dummy, placebo-controlled, multicenter study was conducted in 480 patients aged > or = 12 years with mild-to-moderate persistent asthma. After a 2-week run-in period during which current asthma therapy was discontinued, patients were randomized to receive two inhalations twice daily of budesonide/formoterol pMDI 80/4.5 microg (160/9 microg), budesonide pMDI 80 microg (160 microg), formoterol via dry powder inhaler (DPI) 4.5 microg (9 microg), or placebo.

MAIN OUTCOME MEASURES

Analyses included a subpopulation of 405 patients aged > or = 18 years. PROs included the standardized Asthma Quality of Life Questionnaire (AQLQ(S)), the Medical Outcomes Study (MOS) Sleep Scale, the Patient Satisfaction with Asthma Medication (PSAM) questionnaire, and asthma control variables (recorded via electronic diaries), such as asthma symptoms, rescue medication use, and nighttime awakenings due to asthma. Patient and physician global assessments were collected at the end of the study.

RESULTS

Patients aged > or = 18 years receiving budesonide/formoterol pMDI reported significantly greater improvements from baseline in AQLQ overall and domain scores, MOS Sleep Scale domain scores, and asthma control variables than patients receiving placebo (p < or = 0.033). Improvements from baseline in AQLQ(S) overall and domain scores, daily asthma symptoms scores, percentage of symptom-free days, percentage of rescue medication-free days, and percentage of asthma control days were significantly greater in patients receiving budesonide/formoterol pMDI versus formoterol DPI (p < or = 0.042). Patients receiving budesonide/formoterol pMDI reported significantly greater PSAM scores than did patients in all other treatment arms (p < or = 0.004). Study limitations may include the fact that the formoterol-alone arm used a different device and formulation than the other active arms as well as the absence of a treatment arm with budesonide and formoterol administered concomitantly in separate inhalers. In addition, these results may not be generalized to all patients with asthma, as this analysis included only patients aged > or = 18 years.

CONCLUSIONS

Patients receiving treatment with budesonide/formoterol pMDI experienced significantly greater improvements from baseline in asthma-related quality of life, quality of sleep, and asthma control and greater satisfaction with treatment than patients receiving placebo. The combination of budesonide and formoterol in one pMDI is beneficial in improving how a patient feels and functions as a result of treatment.

Duration of action of the salmeterol/fluticasone combination inhaler administered in the evening: a randomized controlled trial in childhood asthma

OBJECTIVE AND BACKGROUND

To investigate the duration of bronchodilator action of a salmeterol/fluticasone combination (SFC) inhaler when administered in the evening to children with asthma.

METHODOLOGY

DESIGN

A double-blind, placebo-controlled, cross-over study.

SETTING

Hospital inpatient.

SUBJECTS

Fourteen children aged between 4 and 11 years with mild to moderate asthma (FEV(1) > 60% predicted) who exhibited a 15% increase in FEV(1) with bronchodilator.

INTERVENTIONS

SUBJECTS inhaled, in random order, either SFC (100/50 microg) or placebo, via accuhaler, at 20.00 hours on two separate occasions with at least 3 days between study days.

OUTCOME MEASURES

Lung function measurements including FEV(1), PEF, specific airways conductance (sGaw) and maximum expiratory flow at 25-75% of vital capacity were measured at baseline, 2, 12, 16, 20 and 24 h.

RESULTS

For all lung function parameters SFC resulted in significantly greater bronchodilation than placebo for at least 20 h after inhalation. At 24 h, the increase in FEV(1) and PEF compared with placebo was 0.08 L (95% confidence interval: -0.18 to 0.02, P = 0.16) and 27 L/min (95% confidence interval: -47 to -6, P = 0.004), respectively.

CONCLUSIONS

The single administration of SFC via an accuhaler in the evening resulted in significant bronchodilation for at least 20 h in children with asthma.

Montelukast exerts no acute direct effect on NO synthases

The cysteinyl leukotrienes (CysLTs) LTC(4), LTD(4) and LTE(4) are potent proinflammatory lipid mediators that play a central role in inflammation, contraction and remodelling of airways observed in asthmatics. Montelukast, a competitive inhibitor of the cysteinyl leukotriene-1 (CysLT(1)) receptor attenuates asthmatic airway inflammation, contraction and remodelling. As a number of studies have shown that montelukast reduced exhaled nitric oxide (NO) levels, a marker of inflammation that correlates with the severity of asthma, we investigated whether or not a direct inhibition of NO synthase (NOS) by montelukast takes place. In an ex vivo rat lung perfusion and ventilation model the NOS-dependent vasodilation effect after lipopolysaccharide (LPS) infusion was assessed with and without montelukast. Functional organ bath studies using isolated aortic rings from the same species aimed to assess effects of montelukast on the inducible and endothelial NOS isoenzymes (i- and eNOS) as well as on iNOS expression. Neuronal NOS (nNOS) was assessed by field stimulated rabbit corpus cavernosum, and isolated human iNOS enzyme activity was assessed for potential inhibition. Montelukast failed to cause vasoconstriction in LPS challenged rat lung, or to inhibit i- and eNOS activity as well as iNOS expression in aortic rings from the same species. Also the assays for nNOS in rabbit corpus cavernosum and on isolated human iNOS enzyme gave no evidence for a direct inhibition by montelukast in physiological and supraphysiological concentrations up to 10(-4)M. We therefore conclude that montelukast has no acute NOS inhibitor action. Its effect on exhaled NO is therefore probably indirectly mediated by a modulation of the asthmatic airway inflammation.

Combination inhalers containing inhaled corticosteroids and long-acting beta2-agonists: improved clinical efficacy and dosing options in patients with asthma

Combination therapy with inhaled corticosteroids (ICS) and long-acting beta2-agonists (LABA) is a recognized treatment for adults with moderate to severe asthma. The introduction of inhalers containing both an ICS and a LABA simplifies treatment and improves asthma control. This review discusses clinical evidence that budesonide/formoterol and salmeterol/fluticasone are effective and well tolerated in asthma treatment. Moreover, the rapid onset of effect and long duration of action of budesonide and formoterol make once-daily dosing, adjustable maintenance dosing, and the novel treatment strategy of using budesonide/formoterol for maintenance and as needed for symptom relief, valuable treatment options for patients with asthma.

Lung myofibroblasts as targets of salmeterol and fluticasone propionate: inhibition of alpha-SMA and NF-kappaB

Lung myofibroblasts play a major role in the pathophysiology of asthma, contributing not only to tissue remodelling but also to airway inflammation. Nevertheless, only recently, attention has been focused on these cells as potential targets for anti-allergic drugs. Herein, we analysed the pharmacological response of lung myofibroblasts to beta2-agonists associated or not to inhaled corticosteroids, investigating their effects on (i) the constitutive and transforming growth factor-beta (TGF-beta)-induced expression of alpha-smooth muscle actin (alpha-SMA), the main functional marker of myofibroblastic differentiation and contractility; (ii) isometric contraction and (iii) tumour necrosis factor-alpha (TNF-alpha)-induced nuclear translocation of the pro-inflammatory transcription factor nuclear factor-kappaB (NF-kappaB). The beta2-agonist salmeterol (SMl) has on human lung myofibroblasts new direct anti-contractile/anti-inflammatory effects that are amplified by the combined use of low concentrations of the glucocorticoid fluticasone propionate (FP). First, SMl and/or FP (10(-12) M) inhibits the constitutive and TGF-beta-induced expression of alpha-SMA. Second, the two drugs block the TNF-alpha-induced nuclear translocation of the pro-inflammatory transcription factor NF-kappaB. Finally, SMl decreases TNF- alpha-induced production of the inflammatory cytokine IL-6. The complementary anti-inflammatory/ anti-contractile effects displayed by SMl and FP on lung myofibroblasts in vitro may be related to the improvement in lung function and symptom control obtained in vivo by the early use of low doses of glucocorticoids in combination with long-acting beta2-agonists.

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

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

Laryngeal findings in users of combination corticosteroid and bronchodilator therapy

EDUCATIONAL OBJECTIVE

At the conclusion of this article, the readers should be able to 1) describe the laryngeal findings in patients who use combination therapy for asthma, 2) discuss the mechanism of laryngeal irritation from the use of inhalers, and 3) describe possible mechanisms for reducing laryngeal irritation and secondary dysphonia from the use of inhalers.

OBJECTIVES

To describe voice changes and laryngeal findings in patients who are started on combination corticosteroid and bronchodilator therapy in the form of a dry powder inhaler (DPI).

STUDY DESIGN

Retrospective, single-subject design.

METHODS

Retrospective review of 10 consecutive patients meeting inclusion criteria, who presented at the voice center with more than 4 weeks of dysphonia after being started on a combination form of asthma medication for control and maintenance therapy. All patients were nonsmokers and without history of previous identification or excision of vocal pathology. All patients were treated previously with a proton pump inhibitor for gastroesophageal reflux. Laryngeal videostroboscopic evaluations were performed on all patients. Patients were asked to complete a questionnaire regarding their perceived voice change and history of medical maintenance therapy for asthma.

RESULTS

Dysphonia was present in the patients selected for greater than 4 weeks. Patients had been switched to combination therapy after previously using traditional two-drug asthma regimens. In eight of nine patients, the vocal folds demonstrated areas of hyperemia, with plaque-like changes on the surface mucosa. Reduced amplitude of vibration and a reduction in mucosal wave propagation were present on videostroboscopy. Questionnaires revealed that all patients were initiated on combination DPI treatment within the last 6 months.

CONCLUSIONS

Dysphonia caused by a change in the surface mucosa is a side effect from the use of DPI therapy for asthma. The high-impact force during inhalation of the medication and carrier leads to deposition of particles in the upper airway. We believe the extent of mucosal irritation can be minimized by patient education in the proper delivery of DPI. In some cases, however, return of the two medications delivered separately was necessary. The irritation of the laryngeal mucosa and return of normal vibratory parameters occurred in all patients.

Cost advantages of combination asthma therapy

The addition of long-acting beta(2)-adrenoceptor agonist (LABA) therapy to 'low dose' inhaled corticosteroids improves asthma outcomes in terms of lung function, exacerbation rates, and quality of life measures in asthmatic patients who remain symptomatic on low-dose inhaled corticosteroids alone. Such treatment is now included in guidelines of asthma therapy on the basis of class A evidence from large placebo-controlled trials. Data on the cost-benefit of such treatment is less compelling, but suggests that for patients with mild asthma this clinical improvement is gained at the expense of an increase in direct costs (mostly drug costs), whereas for patients with more severe asthma there may be a cost benefit, largely from reduced costs of exacerbations. Recently, combination inhalers containing both LABA and corticosteroid in the same device have been introduced. Although it is said that a single inhaler (with some immediate symptom relief) may aid patient adherence, there are no firm data to support this, nor are there any cost-effectiveness data on this point. Overall, these devices have been priced at less than the two drugs given separately, but prospective studies evaluating costs in clinical settings are required.

Inhaled Salmeterol/Fluticasone Propionate

The salmeterol/fluticasone propionate dry powder inhaler (DPI) [Advair Diskus, Seretide Accuhaler] contains the long-acting beta2-adrenoceptor agonist salmeterol and the inhaled corticosteroid fluticasone propionate. In the US, twice-daily salmeterol/fluticasone propionate 50/250 microg is approved for use in adults with chronic obstructive pulmonary disease (COPD) associated with chronic bronchitis, and in the EU, the twice-daily 50/500 microg dosage is approved for use in patients with severe COPD, repeat exacerbations and significant symptoms despite bronchodilator therapy. In patients with moderate-to-severe COPD, twice-daily inhaled salmeterol/fluticasone propionate 50/250 or 50/500 microg for 24-52 weeks improves predose forced expiratory volume in 1 second (FEV1) significantly more than salmeterol monotherapy, improves postdose or postbronchodilator FEV1 significantly more than fluticasone propionate monotherapy and results in clinically significant improvements in health-related quality of life. Salmeterol/fluticasone propionate 50/500 microg significantly reduced annual COPD exacerbations, especially in severe COPD. Some corticosteroid-related adverse events were increased in recipients of fluticasone propionate with or without salmeterol versus salmeterol monotherapy or placebo; withdrawal from fluticasone propionate, including combination therapy, needs careful management to minimise COPD exacerbations. The DPI combining a corticosteroid and long-acting beta2-agonist provides benefits over monotherapy and may encourage patient compliance in COPD.

Formoterol (Foradil) and medium-high doses of inhaled corticosteroids are more effective than high doses of corticosteroids in moderate-to-severe asthma

This double-blind, randomised, multi-centre, parallel-group study compared the effect of adding Foradil (formoterol fumarate) to existing medium-high doses of inhaled corticosteroids (ICS) with that of doubling the dose of ICS in patients with sub-optimally controlled asthma. After a run-in period, 203 patients with moderate-to-severe asthma who remained symptomatic despite treatment with 500 microg beclomethasone twice daily, were randomised to receive either 12 microg formoterol twice daily (Foradil Aerolizer), Novartis) in addition to beclomethasone 500 microg twice daily, or beclomethasone 1000 microg twice daily and placebo for 12 weeks. The primary efficacy variable was mean morning pre-medication peak expiratory flow (PEF) during the last seven days of treatment. The difference in PEF between treatments was 27.78 l/min in favour of the formoterol/beclomethasone combination (95% CI 13.42, 42.14 l/min, p=0.0002, intention-to-treat population). Significant differences in the urinary cortisol/creatinine ratio between treatment groups at 12 weeks (p=0.001) indicated suppression of the hypothalamic-pituitary-adrenal axis in the patients on beclomethasone 1000 microg twice daily. The addition of formoterol 12 microg twice daily to beclomethasone in patients with asthma who were poorly controlled with beclomethasone 500 microg twice daily was more effective than doubling the ICS dose and resulted in less suppression of the hypothalamic-pituitary-adrenal axis.

Pharmacology of airway inflammation in asthma and COPD

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

Combination therapy: appropriate for everyone?

The severity of asthma often varies throughout the course of the disease. At times the symptoms and underlying inflammation that are characteristic of asthma can worsen. Thus during an episode of viral-induced asthma or during a seasonal increase in asthma severity, a patient may be directed to increase his or her dosage of asthma controllers (i.e., inhaled corticosteroid) or add a long-acting bronchodilator (or other controller medications such as antileukotrienes) to manage symptoms, as recommended in guidelines published by the National Institutes of Health (NIH). Similarly, when symptoms are stable, decreasing dosages or discontinuing certain medications may be appropriate. The recent introduction of a combination product, of a long-acting bronchodilator formulated in the same dry powder device with an inhaled corticosteroid raises new challenges for the step care approach to asthma management recommended by the NIH in 1997. Although unquestionably more convenient for the patient, a combination formulation has the potential to decrease the flexibility required to successfully manage asthma over long periods. In addition, controversy exists regarding long-acting beta-agonists alone because their regular use may mask inflammation in the lung and decrease responsiveness to the bronchodilating effects of rescue medications (i.e., short-acting beta-agonists). The purpose of this article is to help physicians make informed therapeutic decisions for their patients with asthma. It focuses on the advantages and potential disadvantages of using combination products, which contain both an inhaled corticosteroid and a long-acting beta-agonist in the context of the NIH step care approach. Recent publications outlining the use of other add-on controller medications are also discussed.