Inhaled corticosteroids for chronic obstructive pulmonary disease

Use of thiols and implications for the use of inhaled corticosteroids in the presence of oxidative stress in COPD

BACKGROUND

Oxidative stress and persistent airway inflammation are thought to be important contributors to the development of chronic obstructive pulmonary disease (COPD). This review summarizes the evidence for targeting oxidative stress and inflammation in patients with COPD with mucolytic/antioxidant thiols and inhaled corticosteroids (ICS), either alone or in combination.

MAIN BODY

Oxidative stress is increased in COPD, particularly during acute exacerbations. It can be triggered by oxidant air pollutants and cigarette smoke and/or by endogenous reactive oxygen species (ROS) released from mitochondria and activated inflammatory, immune and epithelial cells in the airways, together with a reduction in endogenous antioxidants such as glutathione (GSH). Oxidative stress also drives chronic inflammation and disease progression in the airways by activating intracellular signalling pathways and the release of further inflammatory mediators. ICS are anti-inflammatory agents currently recommended for use with long-acting bronchodilators to prevent exacerbations in patients with moderate-to-severe COPD, especially those with eosinophilic airway inflammation. However, corticosteroids can also increase oxidative stress, which may in turn reduce corticosteroid sensitivity in patients by several mechanisms. Thiol-based agents such as erdosteine, N-acetyl L-cysteine (NAC) and S-carboxymethylcysteine (S-CMC) are mucolytic agents that also act as antioxidants. These agents may reduce oxidative stress directly through the free sulfhydryl groups, serving as a source of reducing equivalents and indirectly though intracellular GSH replenishment. Few studies have compared the effects of corticosteroids and thiol agents on oxidative stress, but there is some evidence for greater antioxidant effects when they are administered together. The current Global Initiative for Chronic Obstructive Lung Disease (GOLD) report supports treatment with antioxidants (erdosteine, NAC, S-CMC) in addition to standard-of-care therapy as they have been demonstrated to reduce COPD exacerbations. However, such studies have demonstrated that NAC and S-CMC reduced the exacerbation risk only in patients not treated with ICS, whereas erdosteine reduced COPD exacerbations irrespective of concomitant ICS use suggesting that erdosteine has additional pharmacological actions to ICS.

CONCLUSIONS

Further clinical trials of antioxidant agents with and without ICS are needed to better understand the place of thiol-based drugs in the treatment of patients with COPD.

Advances in inhaled corticosteroids for the treatment of chronic obstructive pulmonary disease: what is their value today?

INTRODUCTION

As of today, there is still a need to determine which COPD patients may benefit from ICS therapy, whether ICSs are useful in COPD patients without chronic bronchitis, and whether long-acting bronchodilators can reduce the risk of exacerbations in frequent exacerbators even if ICSs are not used, and whether combination therapy including ICSs is helpful in infrequent exacerbators to optimise the use of ICSs in COPD. Nevertheless, in recent years, a fair amount of evidence has been produced that, at least in part, can help define the role of ICSs in COPD better.

AREAS COVERED

Herein, the authors provide an overview of current use of ICS in COPD and discuss their value to the current treatment armamentarium. The article includes discussion of which patients will benefit best from the use of ICSs, their potential uses and adverse effects.

EXPERT OPINION

There is growing agreement on why, in whom, and when ICS therapy can be used in COPD, although the consensus is still lacking because of the heterogeneity of COPD. The use of blood eosinophil counts (BECs) is only helpful in T2 inflammation, while there is a lack of biomarkers indicating the presence of T1 and T17 immunity, which is poorly responsive to ICS. Identifying ICS-sensitive endotypes using specific biomarkers that have yet to be identified and validated is likely to demonstrate that ICSs can influence the natural course of COPD in at least a subset of patients.

Comparative studies of dual bronchodilation in COPD

Dual bronchodilation therapy is becoming the cornerstone for the treatment of COPD because the clinical benefits of LABA/LAMA fixed-dose combinations (FDCs) are now extensively established. Therefore, it not surprising that a number of LAMA/LABA combinations in a single inhaler have now been approved for clinical use as treatments for patients with COPD. Regrettably, very few head-to-head studies between all of the available LABA/LAMA FDCs have been carried out. This makes choosing the most appropriate FDC difficult. Comparative effectiveness research that also uses conventional meta-analyses to compare different care strategies can help generate useful information. A bidimensional comparative analysis across LAMA/LABA FDCs has suggested constant superiority for tiotropium/olodaterol. However, considering that there is not an equivalent amount of evidence on efficacy outcomes for all LAMA/LABA FDCs, a proper comparison between the different LAMA/LABA FDCs cannot be made yet, and the information available is still rather inconsistent.

Pharmacology and Therapeutics of Bronchodilators Revisited

Bronchodilators remain the cornerstone of the treatment of airway disorders such as asthma and chronic obstructive pulmonary disease (COPD). There is therefore considerable interest in understanding how to optimize the use of our existing classes of bronchodilator and in identifying novel classes of bronchodilator drugs. However, new classes of bronchodilator have proved challenging to develop because many of these have no better efficacy than existing classes of bronchodilator and often have unacceptable safety profiles. Recent research has shown that optimization of bronchodilation occurs when both arms of the autonomic nervous system are affected through antagonism of muscarinic receptors to reduce the influence of parasympathetic innervation of the lung and through stimulation of β ₂-adrenoceptors (β ₂-ARs) on airway smooth muscle with β ₂-AR-selective agonists to mimic the sympathetic influence on the lung. This is currently achieved by use of fixed-dose combinations of inhaled long-acting β ₂-adrenoceptor agonists (LABAs) and long-acting muscarinic acetylcholine receptor antagonists (LAMAs). Due to the distinct mechanisms of action of LAMAs and LABAs, the additive/synergistic effects of using these drug classes together has been extensively investigated. More recently, so-called "triple inhalers" containing fixed-dose combinations of both classes of bronchodilator (dual bronchodilation) and an inhaled corticosteroid in the same inhaler have been developed. Furthermore, a number of so-called "bifunctional drugs" having two different primary pharmacological actions in the same molecule are under development. This review discusses recent advancements in knowledge on bronchodilators and bifunctional drugs for the treatment of asthma and COPD. SIGNIFICANCE STATEMENT: Since our last review in 2012, there has been considerable research to identify novel classes of bronchodilator drugs, to further understand how to optimize the use of the existing classes of bronchodilator, and to better understand the role of bifunctional drugs in the treatment of asthma and chronic obstructive pulmonary disease.

Incorporating New Evidence on Inhaled Medications in COPD. The Latin American Chest Association (ALAT) 2019

This document on COPD from the Latin American Chest Association (ALAT-2019) uses PICO methodology to analyze new evidence on inhaled medication and answer clinical questions. The following key points emerged from this analysis: 1) evidence is lacking on the comparison of short-acting vs. long-acting bronchodilators in patients with mild COPD; patients with moderate-to-severe COPD obtain greater benefit from long-acting bronchodilators; 2) the benefits of monotherapy with long-acting antimuscarinic agents (LAMA) and combined therapy with long-acting β₂-agonists and inhaled corticosteroids (LABA/ICS) are similar, although the latter is associated with a greater risk of pneumonia; 3) LABA/LAMA offer greater benefits in terms of lung function and risk of exacerbation than LABA/ICS (the latter involve an increased risk of pneumonia), 4) LAMA/LABA/ICS have greater therapeutic benefits than LABA/LAMA on the risk of moderate-severe exacerbations. With regard to the role of eosinophils in guiding the use of ICS, ICS withdrawal must be considered when the initial indication was wrong or no response is elicited, in patients with side effects such as pneumonia, and in patients with a low risk of exacerbation and an eosinophil blood count of <300 cells/μl. All this evidence, categorized according to the severity of the obstruction, symptoms, and risk of exacerbations, has been used to generate an algorithm for the use of inhaled medication in COPD.

Salmeterol Xinafoate (SX) loaded into mucoadhesive solid lipid microparticles for COPD treatment

Chronic obstructive pulmonary disease (COPD) is one of the main health problems worldwide. It is characterised by chronic inflammation in the lungs that leads to progressive, chronic, largely irreversible airflow obstruction. The use of long-acting β agonists remain today the frontline treatment for COPD with the aim of minimizing side effects and enhancing therapeutic usefulness. To this purpose, in this paper, mucoadhesive solid lipid microparticles (SLMs) containing a long-acting β-2 agonist, Salmeterol Xinafoate (SX) were prepared, characterised (size, z-potential, aerodynamic diameter, turbidimetric evaluations, drug loading and entrapping efficiency) and tested in a model of bronchial epithelial cells. It was demonstrated that the incorporation of SX into SLMs led to the production of particles suitable for inhalation and more efficient than the free molecule at increasing the cAMP expression in bronchial epithelial cells. In conclusion, the prepared systems, due to their aerodynamic behaviour and mucoadhesive properties, could improve the retention time of SX in the lung epithelium and its therapeutic effect, thus representing a good strategy for the treatment of COPD patients.

The Challenges of Precision Medicine in COPD

Pheno-/endotyping chronic obstructive pulmonary disease (COPD) is really important because it provides patients with precise and personalized medicine. The central concept of precision medicine is to take individual variability into account when making management decisions. Precision medicine should ensure that patients get the right treatment at the right dose at the right time, with minimum harmful consequences and maximum efficacy. Ideally, we should search for genetic and molecular biomarker-based profiles. Given the clinical complexity of COPD, it seems likely that a panel of several biomarkers will be required to characterize pathogenetic factors and their course over time. The need for biomarkers to guide the clinical care of individuals with COPD and to enhance the possibilities of success in drug development is clear and urgent, but biomarker development is tremendously challenging and expensive, and translation of research efforts to date has been largely ineffective. Furthermore, the development of personalized treatments will require a much more detailed understanding of the clinical and biological heterogeneity of COPD. Therefore, we are still far from being able to apply precision medicine in COPD and the treatable traits and FEV₁-free approaches are attempts to precision medicine in COPD that must be considered still quite unsophisticated.

Mucoadhesive solid lipid microparticles for controlled release of a corticosteroid in the chronic obstructive pulmonary disease treatment

Aim: Therapeutic efficacy of pulmonary diseases is often limited and drug delivery systems offer new solutions to clinical problems. Solid lipid microparticles (SLMs) are suggested as systems for the delivery of therapeutics to the lung as, because of their size, they are able to deposit into secondary bronchi. Materials & methods: Here, we describe two novel different SLMs using chitosan and alginate such as mucoadhesive polymers and we also studied their biocompatibility and their effectiveness compared with the free drug in controlling senescence and inflammatory processes in cigarette smoke extracts. Results: Data reported show that fluticasone propionate (FP)-loaded SLMs are more effective than FP alone in controlling oxidative stress. Conclusion: The therapeutic approach using FP-loaded microparticles could be a promising strategy for the treatment of the chronic inflammatory pulmonary diseases.

Fixed-Dose Combination Inhalers

In asthma and chronic obstructive pulmonary disease (COPD), an important step in simplifying management and improving adherence with prescribed therapy is to reduce the dose frequency to the minimum necessary to maintain disease control. Fixed-dose combination (FDC) therapy might enhance compliance by decreasing the number of medications and/or the number of daily doses. Furthermore, they have the potential for enhancing, sensitizing, and prolonging the effects of monocomponents. Combination therapy with an inhaled corticosteroid (ICS) and a long-acting β-agonist (LABA) is considered an important approach for treating patients with asthma and patients with severe COPD who have frequent exacerbations. Several ICS/LABA FDCs are now commercially available or will become available within the next few years for the treatment of COPD and/or asthma. Several studies demonstrate that there are a number of added benefits in using combinations of β₂-agonists and antimuscarinic agents. In particular, LABA/long-acting antimuscarinic agent (LAMA) combination seems to play an important role in optimizing bronchodilation. Several once-daily and twice-daily LABA/LAMA FDCs have been developed or are in clinical development. LAMA/ICS FDCs seem to be useful in COPD and mainly in asthma, in patients with severe asthma and persistent airflow limitation. The rationale behind the ICS/LABA/LAMA FDCs seems logical because all three agents work via different mechanisms on different targets, potentially allowing for lower doses of the individual agents to be used, accompanied by improved side effect profiles. In effect, in clinical practice, concomitant use of all three compounds is common, especially in more severe COPD but also in the treatment of adults with poorly controlled asthma despite maintenance treatment with high-dose ICS and a LABA.

Withdrawal of inhaled corticosteroids in COPD: A meta-analysis

BACKGROUND

Conflicting findings exist on the benefit of withdrawal of inhaled corticosteroid (ICS) in chronic obstructive pulmonary disease (COPD). We performed a quantitative synthesis in order to assess real impact of ICS discontinuation in COPD patients.

METHODS

We carried out a meta-analysis via random-effects model on the available clinical evidence to evaluate the effect of ICS discontinuation in COPD. Randomized clinical trials and observational real-life studies investigating the effects of ICS withdrawal on the risk of COPD exacerbation, lung function (forced expiratory volume in 1 s [FEV₁]) and quality of life (St. George's Respiratory Questionnaire [SGRQ]) were identified by searching from published studies and repository databases.

RESULTS

ICS withdrawal did not significantly (P > 0.05) increase the overall rate of COPD exacerbation, although a clinically important increased risk of severe exacerbation was detected (Relative Risk >1.2). ICS withdrawal significantly (P < 0.001) impaired both lung function (-30 ml FEV₁) and quality of life (+1.24 SGRQ units), although in a non-clinically important manner. The time to the first exacerbation was significantly (P < 0.05) shorter in the patients who discontinued ICS.

CONCLUSIONS

The discrepancy between statistical analysis and clinical interpretation of this meta-analytic evaluation demonstrates the strong clinical need in understanding what is the real impact of ICS withdrawal in COPD. ICS discontinuation is a complex procedure that requires a well planned and tailored strategy. Further well designed studies on withdrawal of ICS should be performed by clustering COPD patients with regard to the phenotype characteristics, rate of exacerbations/year, decline of lung function, and quality of life.

Abediterol, a novel long-acting β2-agonist: bronchodilation, safety, tolerability and pharmacokinetic results from a single-dose, dose-ranging, active-comparator study in patients with COPD

BACKGROUND

Abediterol is a novel, once-daily long-acting β2-agonist in development for the treatment of chronic obstructive pulmonary disease (COPD) and asthma in combination with an anti-inflammatory agent. This Phase IIa, randomised, double-blind, crossover study investigated the bronchodilation, safety, tolerability and pharmacokinetics of abediterol in patients with moderate to severe COPD.

METHODS

Seventy patients (aged ≥40 years, Global initiative for chronic Obstructive Lung Disease Stage II/III) were randomised (1:1:1:1:1:1) to single doses of abediterol 0.625, 2.5, 5 or 10 μg, indacaterol 150 μg or placebo. Spirometry was performed up to 36 h post-dose. Pharmacokinetics were assessed in a subset of patients (N = 20). Safety and tolerability were evaluated throughout the study.

RESULTS

Abediterol (all doses) significantly improved change from baseline in trough forced expiratory volume in 1 s (FEV1) compared with placebo (0.102, 0.203, 0.233 and 0.259 L for abediterol 0.625, 2.5, 5 and 10 μg, respectively; all p < 0.0001; primary endpoint). Abediterol 2.5, 5 and 10 μg significantly improved trough FEV1 compared with indacaterol 150 μg (0.092, 0.122 and 0.148 L, respectively; all p < 0.0001). Improvements in bronchodilation were maintained at all time points post-dose versus placebo (all abediterol doses) and from 15 or 30 min post-dose versus indacaterol 150 μg with abediterol 2.5, 5 and 10 μg (all p < 0.05). Abediterol had low systemic exposure; incidence of treatment-emergent adverse events was similar between treatment groups.

CONCLUSIONS

All doses of abediterol (0.625-10 μg) provided clinically and statistically significant, dose-dependent improvements in bronchodilation versus placebo, and abediterol 2.5, 5 and 10 μg gave significant improvements versus indacaterol. All doses of abediterol were safe and well tolerated in patients with COPD.

TRIAL REGISTRATION

Clinicaltrials.gov NCT01425814 . Registered 29 August 2011.

Generation of tailored aerosols for inhalative drug delivery employing recent vibrating-mesh nebulizer systems

Direct drug delivery to the lungs is considered the gold standard for the treatment of a variety of respiratory diseases, owing to the increased therapeutic selectivity of the inhalative approach. Airborne formulations with defined size characteristics are required to improve the deposition pattern within the airways. In this respect, different nebulizer systems have been conceived, which has enabled the generation of respirable medicament mists. Here, vibrating-mesh technology revealed significant potential to overcome the main shortcomings associated with ‘traditional’ devices. Tailored orifice dimensions and defined formulation characteristics are of special interest for the generation of suitable aerosol droplets for inhalative purposes. Ongoing developments in device and formulation design will optimize the clinical outcome of inhalative drug delivery under application of vibrating-mesh technology.

Safety of inhaled corticosteroids for treating chronic obstructive pulmonary disease

INTRODUCTION

The frequent use of inhaled corticosteroids (ICSs), especially at higher doses, has been accompanied by concern about both systemic and local side effects. Patients suffering from chronic obstructive pulmonary disease (COPD) are more at risk from side effects, likely because of the use of higher doses of ICS in COPD to overcome corticosteroid unresponsiveness.

AREAS COVERED

There is considerable concern about increased incidence of pneumonia, osteoporosis and hyperglycemia in diabetic patients and cataracts. The local side effects of ICSs, such as hoarseness and pharyngeal discomfort, oral and oropharyngeal candidiasis, cough during inhalation, and a sensation of thirst, are not usually serious but are of clinical importance because they may lead to patients discontinuing therapy.

EXPERT OPINION

The possibility that ICSs induce adverse side effects should not lead us to avoid their use in patients in whom clinical evidence suggests that they may be helpful. However, clinicians should balance the potential benefits of ICSs in COPD against their potential side effects and always consider using the lowest possible dose to achieve the best possible management.

Fluticasone furoate and vilanterol inhalation powder for the treatment of chronic obstructive pulmonary disease

Fluticasone furoate/vilanterol (FF/VI) is a novel inhaled corticosteroid/long-acting β₂-agonist (ICS/LABA) fixed dose combination that, by simplifying the dosing schedule, allows, for the first time in a member of the ICS/LABA class, a shift from twice-daily to once-daily treatment. FF/VI is delivered via a novel, single-step activation, multi-dose dry powder inhaler for oral inhalation, Ellipta. Regrettably, there are no head-to-head trials that have shown superiority in the safety or efficacy of FF versus other ICSs, but evidence shows that VI has a quicker onset of effect versus salmeterol. However, the clinical utility of this effect in a maintenance medication is still questionable. Furthermore, benefits of FF/VI over twice-daily ICS/LABA comparator have not been shown yet and, in addition, its adverse event profile is generally consistent with the known class effects of an ICS/LABA fixed dose combination. In particular, there is an increase in the risk of pneumonia among patients treated with FF/VI relative to VI, mainly among those who benefit most from FF/VI. Nevertheless, the interesting pharmacological profiles of both FF and VI, the possibility that FF/VI can be administered once-daily, and the attractive characteristics of Ellipta are important features that could help FF/VI to be a successful combination in the treatment of chronic obstructive pulmonary disease.