Inhaled salmeterol: a review of its efficacy in chronic obstructive pulmonary disease

Thyme extract increases mucociliary-beating frequency in primary cell lines from chronic obstructive pulmonary disease patients

Chronic obstructive pulmonary disease (COPD) is a respiratory disorder characterized by a progressive and irreversible airflow limitation. COPD is associated to a chronic inflammatory response with infiltration of inflammatory cells in the surface epithelium of large airways and abnormalities in structure and functions of cilia. Thyme (Thymus vulgaris L.) is a traditional medicinal plant of the Mediterranean area used to treat respiratory disorders. We previously evidenced that thyme extract reduce IL-1beta and IL-8, by downregulating the activated NF-κB levels, suggesting its potential therapeutically use in COPD. Cilia beating frequency (CBF) is dramatically impaired in COPD and different pharmacological agents can modulate cilia function. Herein we evaluated the effect of a commercial thyme extract in modulating CBF by measuring its activity in stimulating cAMP, Ca²⁺ levels and CBF in a MucilAir 3D human COPD airway epithelia reconstituted in vitro system using salmeterol, YM976, isoproterenol and GSK1016790 A as positive controls. Results showed that thyme extract increased cAMP levels starting from 12 h post-treatment, decreased extracellular Ca²⁺ levels and increased the CBF in airway epithelia from COPD donors. Overall, this work demonstrated that thyme extract is effective in stimulating CBF by inducing an increase of cAMP and Ca²⁺ levels, thus supporting its therapeutical use in the treatment of COPD.

In Vitro, Pharmacokinetic, Pharmacodynamic, and Safety Comparisons of Single and Combined Administration of Tiotropium and Salmeterol in COPD Patients Using Different Dry Powder Inhalers

In vitro Andersen cascade impactor-sized mass (ISM) and aerodynamic fine particle mass (FPM) <5 μm for tiotropium and salmeterol combined in a novel inhalation powder formulation containing 7.5 μg tiotropium/25 μg salmeterol (TSHH) were similar (within ±15%) to reference products containing 18 μg of tiotropium (Spiriva® HandiHaler®) (TioHH) and 50 μg of salmeterol (Serevent® Diskus®) (SalD). The pharmacokinetics (PK), pharmacodynamics, safety, and tolerability of the novel fixed-dose TSHH formulation administered once daily was compared with the single-agent therapies TioHH (once daily [qd]) and SalD (twice daily [bid]) and with the jointly administered combination of TioHH (qd) plus SalD (bid) in a randomized, 22-week, open-label, four-way crossover study in 50 patients with chronic obstructive pulmonary disease (COPD). For tiotropium, TSHH and TioHH were bioequivalent based on mean steady-state plasma area under the plasma concentration-time curves (AUC), while the urinary excretion amount was higher for TSHH and not bioequivalent to TioHH. Tiotropium peak plasma concentrations at steady state (C max,ss) were 40% higher with TSHH. For salmeterol, substantial differences were observed in plasma AUCs and Cmax,ss. No significant differences in 8-h forced expiratory volume in 1 s or forced vital capacity were detected for the TSHH (qd) against the combination of TioHH (qd) with SalD (bid). Maintenance therapy with tiotropium plus salmeterol as TSHH or as the jointly administered reference products is superior to either agent alone, safe, and well tolerated in COPD patients. In vitro results were not predictive of clinical PK findings for both tiotropium and salmeterol for the TSHH dry powder inhaler product.

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.

Formoterol

Inhaled formoterol is a long-acting selective beta2-adrenoceptor agonist, with an onset of action of 5 minutes postdose and a bronchodilator effect that lasts for at least 12 hours. Statistically significant and clinically relevant (>120 ml) improvements in lung function [assessed using standardized/normalized area under the forced expiratory volume in 1 second (FEV1) versus time curve (AUC FEV1)] were observed with inhaled formoterol 12 microg twice daily (the approved dosage in the US) compared with placebo in 12-week and 12-month, randomized, double-blind trials in patients with chronic obstructive pulmonary disease (COPD). The bronchodilator efficacy of formoterol 12 microg twice daily was greater than that of oral slow-release theophylline (individualized dosages) in a 12-month trial or inhaled ipratropium bromide 40 microg four times daily in a 12-week trial. Improvement in AUC FEV1 with formoterol, but not theophylline, compared with placebo was observed in patients with irreversible or poorly-reversible airflow obstruction. Formoterol also significantly improved health-related quality of life compared with ipratropium bromide or placebo and significantly reduced symptoms compared with placebo. Combination therapy with formoterol 12 microg twice daily plus ipratropium bromide 40 microg four times daily was significantly more effective than albuterol (salbutamol) 200 microg four times daily plus the same dosage of ipratropium bromide in a 3-week, randomized, double-blind, double-dummy, crossover trial. Inhaled formoterol was well tolerated in clinical trials. The incidence of investigator-determined drug-related adverse events with inhaled formoterol 12 microg twice daily was similar to that with placebo and inhaled ipratropium bromide 40 microg four times daily but lower than that with oral slow-release theophylline (individualized dosages). Importantly, there were no significant differences between formoterol and placebo or comparator drugs in cardiovascular adverse events in patients with COPD and corrected QT interval values within the normal range. In conclusion, inhaled formoterol improved lung function and health-related quality of life and reduced symptoms relative to placebo in clinical trials in patients with COPD. The drug had greater bronchodilator efficacy than oral slow-release theophylline or inhaled ipratropium bromide and showed efficacy in combination with ipratropium bromide. The adverse events profile (including cardiovascular adverse events) with formoterol was similar to that with placebo. Thus, inhaled formoterol may be considered as a first-line option for the management of bronchoconstriction in patients with COPD who require regular bronchodilator therapy for the management of symptoms.

Combining tiotropium and salmeterol in COPD: Effects on airflow obstruction and symptoms

BACKGROUND

Clinical information on 24-h spirometric efficacy of combining tiotropium and salmeterol compared to single-agent therapy is lacking in patients with COPD.

METHODS

A randomized, double-blind, four-way crossover study of 6-week treatment periods comparing combination therapy of tiotropium 18 microg plus qd or bid salmeterol 50 microg versus single-agent therapy. Serial 24-h spirometry (FEV(1), FVC), effects on dyspnea (TDI focal score) and rescue salbutamol use were evaluated in 95 patients.

RESULTS

Tiotropium plus qd salmeterol was superior to tiotropium or salmeterol alone in average FEV(1) (0-24h) by 72 mL and 97 mL (p<0.0001), respectively. Compared to this qd regimen, combination therapy including bid salmeterol provided comparable daytime (0-12h: 12 mL, p=0.38) bronchodilator effects, but significantly more bronchodilation during the night-time (12-24h: 73 mL, p<0.0001). Clinically relevant improvements in TDI focal score were achieved with bronchodilator combinations including salmeterol qd or bid (2.56 and 2.71; p<0.005 versus components). Symptom benefit of combination therapies was also reflected in less need for reliever medication. All treatments were well tolerated.

CONCLUSION

Compared to single-agent therapy, combination therapy of tiotropium plus salmeterol in COPD provided clinically meaningful improvements in airflow obstruction and dyspnea as well as a reduction in reliever medication.

Salmeterol/fluticasone combination in the treatment of COPD

Clinical trials of a combination therapy of an inhaled corticosteroid, fluticasone propionate (FP), with a long-acting β₂-agonist, salmeterol (Sal), have demonstrated a greater improvement in lung function and in quality of life measures after the combination compared with either component of alone. In a subanalysis of the data of the TRISTAN study, Sal/FP reduced exacerbation rates in COPD patients with a baseline FEV₁<50% of predicted. A combination therapy of budesonide and formoterol improved quality of life and FEV₁, and reduced exacerbations better than either component alone. In studies of FP or of Sal/FP in COPD, there was a reduction in all-cause mortality by 25% relative to placebo. Sal/FP has anti-inflammatory effects in COPD airways. FP inhibits markers of systemic inflammation, and it is not known whether Sal/FP has an advantage over FP alone. While long-acting β₂-agonists such as Sal can be recommended for treatment of moderate COPD, addition of inhaled steroid therapy such as FP should be considered in more severe disease.

Chronic obstructive pulmonary disease: role of matrix metalloproteases and future challenges of drug therapy

COPD is a chronic disease of the lung that is characterised by decreased air flow and associated abnormal inflammatory responses of the lungs. A total of 80% of COPD incidences are observed in patients with history of smoking tobacco. The chronic condition of COPD is characterised by airway remodelling, which leads to emphysema and chronic bronchitis. Inflammatory cells of the immune system play a major role in pathophysiology of COPD. High levels of neutrophils, macrophages and CD8(+) T cells have been found in bronchoalveolar lavage samples of COPD patients. Matrix metalloproteases (MMPs), which are secreted by these inflammatory cells, have the enzymatic capacity to cause morphological changes in the lungs and contribute significantly to the COPD state. Increased concentrations of MMP-1, -2, -9, -12 and so on have been found in bronchoalveolar lavage samples of COPD patients compared with non-COPD individuals. COPD is rated as among the top five diseases with high mortality rates and it is estimated that in the next 20 years, the healthcare cost alone for COPD will be US $800 million worldwide. The present drug therapies are neither very efficacious nor cost effective; hence, there is unmet medical need to discover small-molecule drugs for COPD. In this regard, synthetic MMP inhibitors show a great promise for COPD treatment.

A comparison between inhaled salmeterol and theophylline in the short-term treatment of stable chronic obstructive pulmonary disease

BACKGROUND

International guidelines indicate that the long-acting bronchodilators play a key role in the treatment of patients with chronic obstructive pulmonary disease (COPD). The aim of this study was to assess the short term efficacy and safety of 50 and 100 microg bid inhaled salmeterol, compared with placebo and orally dose titrated slow-release theophylline in patients with stable COPD.

METHODS

Thirteen patients (67+/-7 years, three females) with moderate-to-severe COPD (FEV1<70% predicted and >30% predicted) and with poor reversibility (post-bronchodilator FEV1<12% and <200 ml from pre-bronchodilator values) completed this single centre randomised, double-blind, double-dummy, four-phase cross-over clinical trial. Patients were randomised to treatment after a 2-week oral corticosteroid trial and a theophylline titration phase. Each treatment lasted 2 week with a 2-week washout period. Values at the end of treatments were compared.

RESULTS

Inhaled salmeterol at both tested doses was better than placebo in improving lung function (FEV1, FVC, and morning PEF) of stable patients with moderate COPD over a period of 2 weeks. Although slight (about 170 ml, 150 ml, and 120 ml/min on average, for FEV1, FVC, and PEF, respectively) the improvement was significant. The effects seem to improve only slightly with the higher dose. Salmeterol appeared to be more effective than theophylline treatment when compared to placebo, as theophylline improved significantly, but less, the FEV1 (about 80 ml, on average) without affecting any of the other lung function variables. Salmeterol 100 microg was significantly better than theophylline in improving morning PEF. Four patients reported five adverse events while receiving placebo and 2 and 3 patients reported 2 and 3 adverse events, respectively, during salmeterol 50 microg and salmeterol 100 microg phases. None was considered drug related. Five patients experienced 13 adverse events with theophylline treatment, four of which were considered drug related.

CONCLUSION

Inhaled salmeterol improves lung function in stable patients with moderate-to-severe and poorly reversible COPD. The magnitude of improvement in FEV1 observed in this study is similar to that found in longer and larger studies on similar populations of patients. In those studies, that improvement was associated with a better quality of life and less symptoms. Theophylline determined a smaller improvement in FEV1 with more unpleasant side effects that both doses of inhaled salmeterol, though there was no significant difference. It is concluded that salmeterol is an effective and well tolerated therapy, potentially preferable to theophylline, at least in the short-term management of stable COPD.

Tiotropium bromide. A review of its use as maintenance therapy in patients with COPD

Tiotropium bromide (Spiriva) is a long-acting anticholinergic bronchodilator that maintains bronchodilation for at least 24 hours, allowing once-daily administration. The active moiety is the tiotropium cation (tiotropium); tiotropium bromide 22.5 micrograms is equivalent to 18 micrograms of tiotropium cation. Greater improvements in lung function from baseline (primary endpoint mean trough FEV(1)) were observed with inhaled tiotropium 18 micrograms once daily than with placebo in 6-month and 1-year randomized, double-blind trials in patients with COPD. Tiotropium improved lung function (trough FEV(1) response) more effectively than ipratropium bromide (ipratropium) 40 micrograms four times daily in 1-year clinical trials, and was at least as effective as salmeterol 50 micrograms 12-hourly in 6-month trials. Preliminary data suggest that tiotropium alone or in combination with once-daily formoterol has a greater bronchodilator effect than twice-daily formoterol in patients with COPD. Improvements in patients' perception of health-related quality of life (HR-QOL) or dyspnea were greater with tiotropium than with placebo or ipratropium, and were similar to those with salmeterol. Reductions in the frequency and severity of acute exacerbations and in the use of rescue medication were also greater with tiotropium than with ipratropium or placebo. There was no evidence of tachyphylaxis with tiotropium during 1-year clinical trials. Inhaled tiotropium was generally well tolerated in clinical trials. Apart from dry mouth, the type and incidence of adverse events with tiotropium were similar to those with ipratropium, salmeterol or placebo in patients with COPD. In conclusion, inhaled tiotropium 18 micrograms once daily improved lung function, dyspnea, and HR-QOL, and decreased the incidence of acute COPD exacerbations and the use of rescue medication relative to placebo or ipratropium in clinical trials in patients with COPD. Tiotropium was at least as effective as salmeterol in terms of bronchodilator efficacy and improvements in dyspnea or HR-QOL. With the exception of dry mouth, the tolerability profile of tiotropium was similar to that with placebo, ipratropium, or salmeterol. Consequently, inhaled tiotropium is likely to be a valuable option for first-line, long-term maintenance therapy in the management of bronchoconstriction in patients with symptomatic COPD. Tiotropium bromide has a quaternary ammonium structure and acts as an anticholinergic bronchodilator; the active moiety is the tiotropium cation (tiotropium). A 22.5 micrograms dose of tiotropium bromide provides 18 micrograms of tiotropium. Orally inhaled tiotropium bromide antagonizes the muscarinic M(1), M(2), and M(3) receptors located in airway smooth muscle, reversing vagally mediated bronchoconstriction. Receptor binding assays and in vitro tests indicate that tiotropium bromide is kinetically selective for M(1) and M(3) receptors over the M(2) receptor, unlike ipratropium bromide, which is nonselective. Animal and in vitro studies showed that tiotropium bromide was more potent ( approximate, equals 20-fold) than ipratropium bromide in displacing [(3)H]N-methylscopolamine (NMS) from muscarinic receptors, and had a more sustained protective effect (>70% inhibition) against NMS binding. Tiotropium bromide was a more potent inhibitor of bronchial contraction than atropine ( approximate, equals 23-fold), and had a slower onset and markedly longer duration of action than atropine or an equipotent dose of ipratropium bromide. Aerosol particle penetration is improved with tiotropium, without delaying mucus clearance from the lungs. Tiotropium 4.5-36 micrograms once daily for 4 weeks increased mean trough and average FEV(1) and FVC and mean PEFR values from baseline compared with placebo, with no evidence of tachyphylaxis. Improvements in trough FEV(1) from baseline with tiotropium 4.5-36 micrograms were not dose dependent. Based on a lack of dose response, the optimal once-daily tiotropium dosage is 18 micrograms. Steady-state trough FEV(1) values are achieved within 48 hours of commencing tiotrochodilation (for >/=24 hours) and an attenuation of the nocturnal decline in FEV(1) that were unaffected by timing of the daily tiotropium dose were seen in randomized, double-blind, placebo-controlled studies in patients with stable COPD. The drug improved static and dynamic lung hyperinflation (evidenced by reduced trapped air volume and increased tidal volume and end-of-exercise inspiratory capacity), and improved exertional dyspnea (during activities of daily living and exertion) and exercise tolerance compared with placebo in randomized, double-blind studies. In patients with stable COPD, improved sleep-related oxygen desaturation that was unaffected by the timing of the daily dose was seen with tiotropium but not with placebo. Clinically significant treatment-related disorders of conduction or rhythm, or changes in heart rate were not observed with tiotropium in this patient group. Mean maximal plasma concentrations (C(max)) were observed within 5 minutes of inhalation of a single dose of tiotropium 18 micrograms in patients with COPD. Plasma drug levels declined to minimum concentrations (C(min)) within 1 hour of treatment in healthy volunteers. Mean steady-state C(max) concentrations (16 ng/L) were achieved after 2-3 weeks of once-daily inhaled tiotropium 18 micrograms in elderly patients with COPD; tiotropium does not appear to accumulate once steady-state has been achieved.The estimated absolute bioavailability of tiotropium at steady state in healthy volunteers was approximately 20-25%, and approximately 72% of the drug is bound to plasma proteins. Excretion of tiotropium is predominantly renal (through active secretion by the kidneys), although in vitro studies suggest that cytochrome P450 (CYP) oxidation (possibly involving CYP2D6 and CYP3A4 enzymes) may have a minor role. In patients with COPD, renal excretion of the unchanged drug at 24 hours (Ae(24)) was approximately 7%. The mean plasma elimination half-life after single or multiple doses in healthy volunteers and elderly patients with COPD was approximately 5-6 days. The renal clearance and urinary excretion of tiotropium decrease with increasing age; however, these changes are not considered to be clinically significant. Because of altered steady-state C(max), C(min), area under the concentration-time curve, and Ae(24) values, caution is required with tiotropium administration in patients with moderate-to-severe renal impairment. The pharmacokinetics of tiotropium in patients with severe renal or hepatic impairment have not been studied. Tiotropium does not interact with drugs such as cimetidine or ranitidine, which are also eliminated by active renal secretion. Orally inhaled tiotropium bromide has been evaluated as a bronchodilator for the management of patients with COPD in randomized, double-blind 6-month and 1-year trials, and in several shorter studies. In clinical trials, COPD was diagnosed according to the American Thoracic Society guidelines. The bronchodilator effect was expressed as the trough FEV(1) response (the mean change in FEV(1) from baseline measured 1 hour prior to and immediately before a scheduled dose), and was the primary endpoint in all but two clinical trials. The bronchodilator effect with tiotropium 18 micrograms once daily was superior to that with placebo in several well designed trials in patients with COPD. Moreover, greater improvements in mean peak and average FEV(1) responses occurred with tiotropium but not with placebo. Mean trough, peak, and average FVC responses, and weekly mean morning and evening PEFR values were also improved to a greater extent with tiotropium than with placebo. Tiotropium demonstrated a greater bronchodilator effect than ipratropium bromide (hereafter referred to as ipratropium when used at approved dosages) 40 micrograms four times daily in two 1-year trials in patients with COPD. Mean peak and average FEV(1), mean trough FVC responses, and weekly mean morning and evening PEFR values were also increased to a greater extent with tiotropium than with ipratropium. In one of the two 6-month trials that compared the efficacy of tiotropium with that of inhaled salmeterol 50 micrograms twice daily, greater improvements from baseline in mean trough, peak, and average FEV(1) and FVC responses were seen with tiotropium than with salmeterol. Increases in weekly mean evening, but not morning, PEFR values were generally greater with tiotropium than salmeterol. In the second trial, improvement in the primary endpoint (mean trough FEV(1) response from baseline) with tiotropium or salmeterol was similar, although peak and average responses were superior with tiotropium. Preliminary results from a 6-week crossover study in patients with COPD suggested that tiotropium alone or in combination with once-daily formoterol improved mean trough and average FEV(1) and trough FVC values from baseline to a greater extent than twice-daily formoterol. More patients achieved a clinically important improvement (increase of >/=1 unit) in the transitional dyspnea index focal score (a measure of dyspnea-related impairment) with tiotropium than with placebo in the 1-year trials. Tiotropium was superior to ipratropium in 1-year trials, and was at least as effective as salmeterol in 6-month trials, in achieving a clinically important improvement in focal scores. Tiotropium recipients experienced fewer COPD exacerbations than placebo or ipratropium recipients and had fewer and shorter COPD-related hospitalizations compared with placebo recipients. Unlike salmeterol, tiotropium lengthened the time to onset of the first exacerbation and decreased the number of exacerbations compared with placebo in two 6-month trials. Similar proportions of tiotropium, salmeterol, and placebo recipients required COPD-related hospitalizations. (ABSTRACT TRUNCATED)

Managing patients with recurrent acute exacerbations of chronic bronchitis: a common clinical problem

Chronic obstructive pulmonary disease (COPD) affects 15 million people and is the fourth leading cause of death in the United States. It places a considerable burden on the healthcare system, with exacerbations contributing to a significant proportion of this burden. Patients with recurrent exacerbation, who experience more than 2 exacerbations per year, are especially difficult to manage. Several potential host, pathogen, and treatment factors can be identified that contribute to recurrent exacerbation. Patients with recurrent exacerbations are often exposed to frequent courses of antimicrobials. Therefore, antimicrobial resistance among common bacterial pathogens is likely to be prevalent in this group of patients, and further complicates therapy in this already difficult-to-treat patient population. In the management of patients with recurrent exacerbation, one goal should be to decrease the frequency of exacerbations, for which several strategies are suggested. In this article, we will review available literature identified through an extensive search of Medline and PubMed on the characteristics and approach to management of these difficult-to-treat patients. There is a substantial need for more research to understand the etiology and identify efficacious interventions to reduce the frequency of exacerbations of COPD.

Treatment of stable chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a readily diagnosable disorder that responds to treatment. Smoking cessation can reduce symptoms and prevent progression of disease. Bronchodilator therapy is key in improvement of lung function. Three classes of bronchodilators-beta agonists, anticholinergics, and theophylline-are available and can be used individually or in combination. Inhaled glucocorticoids can also improve airflow and can be combined with bronchodilators. Inhaled glucocorticoids, in addition, might reduce exacerbation frequency and severity as might some bronchodilators. Effective use of pharmacotherapy in COPD needs integration with a rehabilitation programme and successful treatment of co-morbidities, including depression and anxiety. Treatment for stable COPD can improve the function and quality of life of many patients, could reduce admissions to hospital, and has been suggested to improve survival.

Therapy for chronic obstructive pulmonary disease in the 21st century

Chronic obstructive pulmonary disease (COPD) is a common, smoking-related, severe respiratory condition characterised by progressive, irreversible airflow limitation. Current treatment of COPD is symptomatic, with no drugs capable of halting the relentless progression of airflow obstruction. Better understanding of the airway inflammation, oxidative stress and alveolar destruction that characterise COPD has delineated new disease targets, with consequent identification of novel compounds with therapeutic potential. These new drugs include aids to smoking cessation (e.g. bupropion) and improvements to existing therapies, for example long-acting rather than short-acting bronchodilators, as well as combination therapy. New antiproteases include acyl-enzyme and transition state inhibitors of neutrophil elastase (e.g. sivelestat and ONO-6818), matrix metalloprotease inhibitors (e.g. batimastat), cathepsin inhibitors and peptide protease inhibitors (e.g. DX-890 [EPI-HNE-4] and trappin-2). New antioxidants include superoxide dismutase mimetics (e.g. AEOL-10113) and spin trap compounds (e.g. N-tert-butyl-alpha-phenylnitrone). New anti-inflammatory interventions include phosphodiesterase-4 inhibitors (e.g. cilomilast), inhibitors of tumour necrosis factor-alpha (e.g. humanised monoclonal antibodies), adenosine A(2a) receptor agonists (e.g. CGS-21680), adhesion molecule inhibitors (e.g. bimosiamose [TBC1269]), inhibitors of nuclear factor-kappaB (e.g. the naturally occurring compounds hypoestoxide and (-)-epigallocatechin-3-gallate) and activators of histone deacetylase (e.g. theophylline). There are also selective inhibitors of specific extracellular mediators such as chemokines (e.g. CXCR2 and CCR2 antagonists) and leukotriene B(4) (e.g. SB201146), and of intracellular signal transduction molecules such as p38 mitogen activated protein kinase (e.g. RWJ67657) and phosphoinositide 3-kinase. Retinoids may be one of the few potential treatments capable of reversing alveolar destruction in COPD, and a number of compounds are in clinical trial (e.g. all-trans-retinoic acid). Talniflumate (MSI-1995), an inhibitor of human calcium-activated chloride channels, has been developed to treat mucous hypersecretion. In addition, the purinoceptor P2Y(2) receptor agonist diquafosol (INS365) is undergoing clinical trials to increase mucus clearance. The challenge to transferral of these new compounds from preclinical research to disease management is the design of effective clinical trials. The current scarcity of well characterised surrogate markers predicts that long-term studies in large numbers of patients will be needed to monitor changes in disease progression.

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.

Addition of an extra dose of salmeterol Diskus to conventional dose of salmeterol Diskus in patients with COPD

Patients experiencing dyspnoea can request an additional dose of salmeterol during the dose interval for the control of their symptoms, although under treatment with salmeterol. In this study we have explored the effects on respiratory function of an additive dose of salmeterol Diskus in 15 chronic obstructive pulmonary disease (COPD) patients in regular treatment with a conventional dose of 50 microg salmeterol. On two different days, patients inhaled 50 microg Diskus. After 240 min, they inhaled additional 50 microg salmeterol Diskus (salmeterol arm) or placebo Diskus (placebo arm). Lung function was controlled before first drug administration and 0.5, 1, 2, 3, 4, 4.5, 6, 8, 10, and 12 h thereafter. The mean (95% CI) peak increase in FEV1 from baseline was reached after 4 h in the salmeterol arm (0.174 L; 0.144-0204) and after 5 h (0.141 L; 0.115-0.168) inthe placebo arm; after 12 h, the mean (95% Cl) increase in FEV1 from basal values was still 0.149 L (0.119-0.179) in salmeterol arm, but only 0.041 L (0.017-0.064) in placebo arm. The mean (95% CI) FEV1 AUC0-12h for all patients were 2.01 (1.72-2.30) L when salmeterol was added and 1.30 (1.03-1.58) L when placebo was inhaled. The difference (mean; 95% CI) between the FEV1 AUC0-12h of the two arms (0.71 L; 0.47-0.95) was statistically significant (P<0.0001), although the difference (mean; 95% CI) between the FEV1 AUC0-4h of the two treatments (0.08 L; -0.02-0.18) was notstatistically significant (P=0.126). The addition of an extra dose of salmeterol did not significantly increase the heart rate or decrease the SpO2. This study suggests that the addition of an extra dose of salmeterol does not give room for further increase in peak FEV1, but the effect of adding salmeterol to salmeterol is largely additive when considering the duration of action and safe.