The future of combining inhaled drugs for COPD

Formulation and evaluation of inhaled Sildenafil-loaded PLGA microparticles for treatment of pulmonary arterial hypertension (PAH): A novel high drug loaded formulation and scalable process via hot melt extrusion technology (Part Ⅰ)

In recent years, several techniques were employed to develop a local sustained pulmonary delivery of sildenafil citrate (SC) as an alternative for the intravenous and oral treatment of pulmonary arterial hypertension (PAH). Most of these methods, however, need to be improved due to limitations of scalability, low yield production, low drug loading, and stability issues. In this study, we report the use of hot-melt extrusion (HME) as a scalable process for making Poly (lactic-co-glycolic acid) (PLGA) microparticles with high SC load. The prepared particles were tested in vitro for local drug delivery to the lungs by inhalation. Sodium bicarbonate was included as a porogen in the formulation to make the particles more brittle and to impart favorable aerodynamic properties. Six formulations were prepared with different formulation compositions. Laser diffraction analysis was used to estimate the geometric particle size distribution of the microparticles. In-vitro aerodynamic performance was evaluated by the next-generation cascade impactor (NGI). It was reported in terms of an emitted dose (ED), an emitted fraction (EF%), a respirable fraction (RF%), a fine particle fraction (FPF%), a mass median aerodynamic diameter (MMAD), and geometric standard deviation (GSD). The formulations have also been characterized for surface morphology, entrapment efficiency, drug load, and in-vitro drug release. The results demonstrated that PLGA microparticles have a mean geometric particle size between 6 and 14 µm, entrapment efficiency of 77 to 89 %, and SC load between 17 and 33 % w/w. Fifteen percent of entrapped sildenafil was released over 24 h from the PLGA microparticles, and seventy percent over 7 days. The aerodynamic properties included fine particle fraction ranging between 19 and 33 % and an average mass median aerodynamic diameter of 6-13 µm.

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.

Adherence to COPD treatment: Myth and reality

COPD is a chronic disease in which effective management requires long-term adherence to pharmacotherapies but the level of adhesion to the prescribed medications is very low and this has a negative influence on outcomes. There are several approaches to detect non-adherence, such as pharmacy refill methods, electronic monitoring, and self-report measures, but they are all burdened with important limitations. Medication adherence in COPD is multifactorial and is affected by patients (health beliefs, cognitive abilities, self-efficacy, comorbidities, psychological profile, conscientiousness), physicians (method of administration, dosing regimen, polypharmacy, side effects), and society (patient-prescriber relationship, social support, access to medication, device training, follow-up). Patient-health care professional communication, especially that between patient and physician or pharmacist, is central to optimizing patient adherence. However, the most realistic approach is to keep in mind that non-adherence is always possible, indeed, probable.

Efficacy and safety of indacaterol/glycopyrronium fixed-dose combination in mild-to-moderate COPD patients symptomatic on tiotropium in Korea: study protocol for a randomized controlled trial

BACKGROUND

Long-acting bronchodilator monotherapy (long-acting β2-agonist [LABA] or long-acting muscarinic antagonist [LAMA]) is extensively used for treatment of patients with chronic obstructive pulmonary disease (COPD) with mild-to-moderate airflow limitation. However, a substantial number of patients remain symptomatic despite treatment with a single bronchodilator, necessitating a change in therapy.

METHODS

This 12-week, randomized, multicenter, open-label, phase IV study aims to show that the once-daily indacaterol/glycopyrronium (IND/GLY) 110/50 μg fixed-dose LABA/LAMA combination results in an improved lung function in symptomatic patients with mild-to-moderate COPD who switch from once-daily tiotropium 18 μg. The study aims to enroll a total of 404 symptomatic patients in Korea with mild-to-moderate COPD who received tiotropium for at least 12 weeks prior to the study initiation. The primary objective of this study is to demonstrate the superiority of IND/GLY over tiotropium in terms of trough forced expiratory volume in 1 second (FEV1) following 12 weeks of treatment. Secondary endpoints include the pre-dose trough FEV1 after 4 weeks of treatment, transition dyspnea index (TDI) total score, COPD assessment test (CAT) total score, and rescue medication use following the 12-week treatment, and safety assessment over the 12-week treatment.

DISCUSSION

This study intends to establish the use of LABA/LAMA combination therapy in symptomatic patients with mild-to-moderate COPD by demonstrating the superiority of IND/GLY over tiotropium monotherapy.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02566031 . Registered on 10 August 2015.

Patient perspectives on fluticasone-vilanterol versus other corticosteroid combination products for the treatment of asthma

OBJECTIVE

Fluticasone furoate (FF), an inhaled corticosteroid (ICS), and vilanterol (VI), a long-acting beta2 receptor agonist (LABA), is a new combination used in an Ellipta(®) device. This article compares FF-VI to other ICS-LABA combinations available, particularly emphasizing product selection from the patient perspective.

DATA SOURCES

A PubMED and EMBASE search completed in October 2015 identified trials using the MeSH terms "fluticasone", "vilanterol", and "asthma". Additional information was gathered from references cited in the identified publications, the manufacturer, package insert, and ClinicalTrials.gov registry.

STUDY SELECTION/DATA EXTRACTION

Preference was given to randomized controlled clinical trials. Animal trials, trials for COPD, and non-English sources were excluded.

DATA SYNTHESIS

Seven efficacy trials of FF-VI in asthma were identified. Only one (24 weeks) trial compared FF-VI to another ICS-LABA combination (fluticasone propionate-salmeterol). Primary outcomes (usually lung function) and secondary outcomes (eg, quality of life and symptom scores) were comparable. In three FF-VI safety trials, the type and frequency of common adverse reactions (ie, thrush and dysphonia) were similar to those in clinical trials. Over 90% of subjects rated the Ellipta(®) device as "easy to use" and demonstrated correct device technique initially and at 4 weeks.

CONCLUSION

Individuals may have drug- and device-specific preferences that should be incorporated into therapeutic decision making. Limited data indicate that clinical and patient-oriented efficacy/safety outcomes of FF-VI are likely comparable to other available combinations for adults with asthma. Patient-friendly features include once-daily dosing, flexibility of dose timing, and design/ease of the use of the device. Additional larger and long-term comparative studies are needed to determine whether these features translate into greater efficacy, safety, patient preference, or adherence versus other ICS-LABA combinations. In the next few years, the availability of less expensive generic ICS-LABA products may strongly influence patient preference.

Can the anti-inflammatory activities of β2-agonists be harnessed in the clinical setting?

Beta2-adrenoreceptor agonists (β2-agonists) are primarily bronchodilators, targeting airway smooth muscle and providing critical symptomatic relief in conditions such as bronchial asthma and chronic obstructive pulmonary disease. These agents also possess broad-spectrum, secondary, anti-inflammatory properties. These are mediated largely, though not exclusively, via interactions with adenylyl cyclase-coupled β2-adrenoreceptors on a range of immune and inflammatory cells involved in the immunopathogenesis of acute and chronic inflammatory disorders of the airways. The clinical relevance of the anti-inflammatory actions of β2-agonists, although often effective in the experimental setting, remains contentious. The primary objectives of the current review are: firstly, to assess the mechanisms, both molecular and cell-associated, that may limit the anti-inflammatory efficacy of β2-agonists; secondly, to evaluate pharmacological strategies, several of which are recent and innovative, that may overcome these limitations. These are preceded by a consideration of the various types of β2-agonists, their clinical applications, and spectrum of anti-inflammatory activities, particularly those involving adenosine 3',5'-cyclic adenosine monophosphate-activated protein kinase-mediated clearance of cytosolic calcium, and altered gene expression in immune and inflammatory cells.

Combination of fluticasone furoate and vilanterol for the treatment of chronic obstructive pulmonary disease

OBJECTIVE

To evaluate the efficacy and safety of the combination of fluticasone furoate/vilanterol (FF/VI) and compare it with other inhaled combination corticosteroid/long-acting β₂-receptor agonists for maintenance treatment of chronic obstructive pulmonary disease (COPD).

DATA SOURCES

A PubMed and EMBASE search in June 2013 using the MeSH terms fluticasone and vilanterol identified trials using this combination for COPD. Additional information was gathered from references cited in the identified publications, the manufacturer, and package insert as well as the ClinicalTrials.gov registry.

STUDY SELECTION/DATA EXTRACTION

Preference was given to randomized controlled clinical trials. Data from animal trials, clinical trials for asthma, and non-English sources were excluded.

DATA SYNTHESIS

Given once daily, FF/VI improves trough forced expiratory volume at 1 s by about 230 mL in a 28-day trial versus placebo. However, a more modest increase (100-130 mL) was seen in 2 longer 28-week trials. In the longest trial of 1 year, a slight but significant decrease in the yearly rate of moderate plus severe exacerbations, the time to first moderate or severe exacerbation, and the frequency of exacerbations requiring systemic corticosteroids was seen. There was no difference in the rate of exacerbations requiring hospitalization. The product appears to have the adverse effect profile typical of its class.

CONCLUSIONS

Of the inhaled corticosteroid/long-acting β₂ receptor agonist combinations, VI/FF is the first allowing once-daily dosing. Similar to the other combination products, it may slightly decrease the incidence of COPD exacerbations in the patient subset with Global Initiative for Chronic Obstructive Lung Disease risk category C or D. There are no direct safety or efficacy data comparing this with other available inhaled combination products. The once-daily dosing might improve adherence in select patients. The Ellipta delivery device may assist some who are unable to use other devices correctly.

Sports doping: emerging designer and therapeutic β2-agonists

Beta2-adrenergic agonists, or β2-agonists, are considered essential bronchodilator drugs in the treatment of bronchial asthma, both as symptom-relievers and, in combination with inhaled corticosteroids, as disease-controllers. The use of β2-agonists is prohibited in sports by the World Anti-Doping Agency (WADA) due to claimed anabolic effects, and also, is prohibited as growth promoters in cattle fattening in the European Union. This paper reviews the last seven-year (2006-2012) literature concerning the development of novel β2-agonists molecules either by modifying the molecule of known β2-agonists or by introducing moieties producing indole-, adamantyl- or phenyl urea derivatives. New emerging β2-agonists molecules for future therapeutic use are also presented, intending to emphasize their potential use for doping purposes or as growth promoters in the near future.