The rejuvenated pressurised metered dose inhaler

The pressurised metered-dose inhaler (pMDI) has now been available for 50 years. Once regarded as an inefficient and difficult-to-use device, the technology has evolved significantly over the last few years, particularly since the introduction of novel formulations containing hydrofluoroalkane (HFA) propellants. Many modern HFA pMDIs deposit drug more efficiently in the lungs, impact less forcefully on the back of the throat and feel less cold than their chlorofluorocarbon pMDI counterparts. An improved understanding of technical factors makes it possible to design HFA pMDIs to have specific spray properties, particularly in terms of fine particle dose and spray velocity. Device technology has also progressed with the introduction of compact and convenient breath-actuated, breath-coordinated and velocity-modifying devices, which help patients to achieve a reliable lung dose. Although it faces competition from dry powder inhalers and possibly from novel soft-mist inhalers containing liquid formulations, the rejuvenated HFA pMDI is a device with a significant future for asthma, chronic obstructive pulmonary disease and wider treatment indications.     

Comparative lung delivery of salbutamol given via Turbuhaler and Diskus dry powder inhaler devices

Objective: The environmental concerns surrounding the use of chlorofluorocarbons (CFC) have led to a resurgence of interest in dry powder inhaler devices. The aim of our study was to compare two commonly used dry powder inhaler devices, namely the Turbuhaler and Diskus. Methods: Eight healthy volunteers with a mean (SEM) age of 21 years (0.8) were studied using a randomised single-investigator blind crossover design. Single doses of 1.2 mg salbutamol as Turbuhaler (12 × 100 μg) and Diskus (6 × 200 μg) were administered over 6 min. Mouth rinsing was performed after every inhalation. Lung delivery from each device was assessed by measuring the early plasma salbutamol profile at 5, 10, 15 and 20 min after inhalation. Results: Significant differences in lung delivery were found between the Diskus and the Turbuhaler for salbutamol C_max 3.21 vs 4.04 ng · ml⁻¹, respectively and C_av 2.65 vs 3.73 ng · ml⁻¹, respectively. This amounted to a 1.28-fold difference (95% CI 1.09 to 1.45) between these devices for C_max and a 1.42-fold difference (95% CI 1.57 to 1.66) for C_av. Conclusion: We have demonstrated that, in vivo, the Turbuhaler dry powder inhaler produces significantly greater lung delivery of salbutamol than the Diskus. This illustrates that dry powder inhaler devices may have different in vivo deposition characteristics. Received: 27 January 1997 / Accepted in revised form: 21 May 1997     

干粉吸入剂的有效性及质量评价

综述了影响干粉吸入剂有效性的因素,并对其体内外测定方法及质量控制进行了概述.     

Relative bioavailability of salbutamol to the lung following inhalation when administration is prolonged

AIMS: Urinary salbutamol post-inhalation has been shown to be an index of lung deposition. The possibility of using the urinary method for prolonged periods of inhalation (such as nebulized therapy) has been evaluated. METHODS: On separate study days volunteers received salbutamol 5 x 100 microg via either oral administration (ORAL), oral with 5 g oral charcoal (ORAL + C), inhaled from a metered dose inhaler (MDI) or MDI plus 5 g oral charcoal (MDI + C). Each dose was separated by 2 min, i.e. administration time of 8 min. Urine samples were provided at 0, 30, 40, 60 and 120 min postdose. Also seven subjects inhaled 5x100 microg doses from the MDI on five separate occasions and provided urine 0-30 min post dose. RESULTS: No salbutamol was detected in urine samples following ORAL + C. The mean (s.d.) amounts of salbutamol excreted in the urine in the first 30 min post ORAL, MDI and MDI + C were 0.42 (0.55), 11.01 (3.77) and 11.60 (3.68) microg, respectively. The ratio of urinary salbutamol following MDI and MDI + C to ORAL in the 0-30 min collection period was 26.2 and 27.8, and between 30 and 40 min postdose was 5.1 and 4.7, respectively. There was no difference between urinary salbutamol over the first 30 min following MDI and MDI + C with a mean ratio (90% confidence interval) of 95.6 (84.0, 107.2). The mean (s.d.) coefficient of variation for the 30 min urinary salbutamol elimination following inhalation of 5 x 100 microg doses from the MDI by seven subjects (on 5 separate study days) was 9.4 (2.3)%. CONCLUSIONS: The 30 min urinary salbutamol method can be used for an inhalation period of up to 8 min to identify the relative bioavailability to the lung. Samples taken after this time period are affected by excretion of the oral absorbed fraction. Most nebulisers deliver their dose within this administration time.     

Relative lung and total systemic bioavailability following inhalation from a metered dose inhaler compared with a metered dose inhaler attached to a large volume plastic spacer and a jet nebuliser

OBJECTIVE: To compare the lung and systemic delivery of salbutamol following inhalation from a metered dose inhaler (MDI), a MDI attached to a spacer (MDI+SP) and a nebuliser (NEB) using a urinary pharmacokinetic method. METHOD: Twelve healthy subjects each provided urine samples at 0, 30 min and pooled up to 24 h after the start of 5 x 100 microg salbutamol inhaled from MDI and MDI + SP and after 2.5 mg was delivered by NEB. Following nebulisation, the amount of salbutamol trapped on an exhalation filter together with that remaining in the apparatus was determined. The amount left in the spacer and that leaving the MDI mouthpiece was also determined. Thus, for all the methods, the amount available for inhalation from each study dose was determined. RESULTS: The mean (+/- SD) 30-min urinary excretion amounts of salbutamol for MDI, MDI+SP and NEB were 12.6+/-3.5, 27.1+/-6.0 and 16.1+/-4.6 microg, respectively. The mean ratios (90% confidence intervals) for MDI+SP compared with MDI and NEB were 230.2 (186.7, 273.8) and 183.0 (146.4, 219.7) (both P values<0.001), respectively, while that between MDI and NEB was 134 (110.4, 159.1) (P < 0.05). The mean (+/-SD) 24-h urinary excretion values for salbutamol and its metabolite were 287.0+/-46.5, 198.1+/-34.7 and 253.4+/-138.3 microg, respectively. Following inhalation a mean of 202.9+/-51.5 microg was left in the spacer. Similarly, after nebulisation 1387.7+/-88.9 microg was left in the nebuliser chamber, 26.3+/-8.0 microg in the mouthpiece and 553.8+/-68.5 microg exhaled. The mean emitted dose from the MDI was 88.4+/-6.1 microg per actuation. When normalised for the amounts available for inhalation, the mean amounts of salbutamol excreted in the urine during the first 30 min were 2.86+/-0.78, 9.15+/-1.69 and 3.06+/-0.70% following MDI, MDI + SP and NEB, respectively. CONCLUSION: Five 100-microg doses inhaled from a metered dose inhaler attached to a spacer delivered more to the lungs and less to the systemic circulation than either the same doses from a metered dose inhaler used alone or five times the dose given via a jet nebuliser. Spacers should be routinely used instead of nebulisers to manage patients unless they are short of breath.     

干粉吸入剂的粉末定量分装设备浅析

干粉吸入剂是一种新兴呼吸道给药剂型,其吸入粉末的分装装置不同于常见的口服固体粉末分装装置。本文综述国际上常用的干粉吸入剂的粉末定量分装装置,包括标准定量器装置装置、真空滚筒分装装置、Xcelodose精确粉末微定量装置等,同时介绍几种较新的、处于研发阶段的粉末分装装置。     

新型环索奈德胶囊型干粉吸入剂的研制及其质量研究

目的:研制用于治疗哮喘的环索奈德胶囊型干粉吸入剂,建立其含量测定方法,并对其稳定性进行初步考察。方法:用高效液相色谱-紫外法检测环索奈德干粉吸入剂中主药环索奈德及其有关物质的含量。将主药与辅料混合后,以含量均匀度和肺部沉积率为指标进行处方筛选,考察制剂的有关物质和影响因素,并进行了加速稳定性和长期留样稳定性试验。结果:建立的高效液相色谱法,色谱条件如下:色谱柱为Alltima C18(250 mm×4.6mm,5μm);流动相为乙醇-水(65∶35);流速为1.2 mL.min-1;检测波长为243 nm。最后选择乳糖作为辅料,确定了最佳处方和工艺,获得了较好的含量均匀度和肺部沉积率(约19%)。稳定性结果显示,本制剂应置于阴凉、干燥处保存,在室温下保存至少在1年内稳定,长期放置稳定性在继续考察。结论:建立的高效液相色谱法适合于环索奈德胶囊型干粉吸入剂的日常质量控制,研制的制剂处方稳定。     

Improved lung delivery from a passive dry powder inhaler using an Engineered PulmoSphere powder

Purpose. To assess the pulmonary deposition and pharmacokinetics of an engineered PulmoSphere® powder relative to standard micronized drug when delivered from passive dry powder inhalers (DPIs). Methods. Budesonide PulmoSphere (PS_bud) powder was manufactured using an emulsion-based spray-drying process. Eight healthy subjects completed 3 treatments in crossover fashion: 370 g budesonide PulmoSphere inhaled from Eclipse® DPI at target PIF of 25 L·min^-1 (PS_bud25), and 50 L·min^-1 (PS_bud50), and 800 g of pelletized budesonide from Pulmicort® Turbuhaler® at 60 L·min^-1(TH_bud60). PS_bud powder was radiolabeled with ^99mTc and lung deposition determined scintigraphically. Plasma budesonide concentrations were measured for 12 h after inhalation. Results. Pulmonary deposition (mean ± sd) of PS_bud was 57 ± 7% and 58 ± 8% of the nominal dose at 25 and 50 L·min^-1, respectively. Mean peak plasma budesonide levels were 4.7 (PS_bud25), 4.0 (PS_bud50), and 2.2 ng·ml^-1 (TH_bud60). Median t_max was 5 min after both PS_bud inhalations compared to 20 min for Turbuhaler (P < 0.05). Mean AUCs were comparable after all inhalations, 5.1 (PS_bud25), 5.9 (PS_bud50), and 6.0 (TH_bud60) ng·h·ml^-1. The engineered PS_bud powder delivered at both flow rates from the Eclipse® DPI was twice as efficiently deposited as pelletized budesonide delivered at 60 L·min^-1 from the Turbuhaler. Intersubject variability was also dramatically decreased for PS_bud relative to TH_bud. Conclusion. Delivery of an engineered PulmoSphere formulation is more efficient and reproducible than delivery of micronized drug from passive DPIs.     

Rational design of a dry powder inhaler: device design and optimisation

Objectives As part of the development of a dry powder inhalation system for the treatment of asthma and chronic obstructive pulmonary disease, this work specifically aimed at the systematic, however, cost-effective and efficient development of an inhalation device. Methods Based on theoretical design considerations and an initial inhaler prototype, the concept of a modular inhaler was developed. The modular inhaler was used for the systematic evaluation of the influence of the inhaler's inner dimensions on the resistance to the air flow and the in-vitro deposition characteristics of the inhalation system by using statistical design of experiments and cascade impaction analysis. Key findings A reliable statistical model enabled the accurate prediction of the device resistance of any combination of inner dimensions of the inhaler. In conjunction with results from in-vitro deposition studies, this allowed for the definition of optimised inner dimensions of the inhaler to maximise the fine particle fraction and minimise oropharyngeal deposition within the desired range of the inhaler's resistance to air flow. Conclusions The concept of the modular inhaler and statistical design and evaluation of experiments proved to be important tools for an efficient and successful product development. Eventually, the approaches described and the knowledge obtained enabled the cost-effective development and design of a technically feasible and competitive dry powder inhaler.     

驱动器的规格与吸入辅助装置对气雾剂体外沉积性质的影响

目的 考察驱动器的规格——孔径、孔长以及吸入辅助装置的使用对气雾剂体外沉积性质的影响.方法 以自制丙酸氟替卡松混悬型气雾剂为模型药物,装配不同规格的驱动器,使用Andersen多级撞击器(Andersen cascade impactor,ACI)测定体外沉积率;将丙酸氟替卡松气雾剂装配筛选好的特定规格的驱动器,分别在不使用吸入辅助装置与使用吸入辅助装置的情况下,对体外沉积性质进行对比研究.结果 在孔径固定的情况下,随着孔长的延长,驱动器的残留量降低,Andersen多级撞击器装置的L型连接管沉积量增加,微细粒子剂量降低.在孔长固定的情况下,随着孔径的增加,驱动器的残留量降低,Andersen多级撞击器装置的L型连接管沉积量增加,微细粒子剂量降低.根据试验结果、混悬型气雾剂本身的剂型特点以及驱动器的实际使用情况,最终,将0.42 mm孔径、0.70 mm孔长的驱动器作为优选驱动器;在使用吸入辅助装置的情况下,Andersen多级撞击器装置L型连接管的沉积量极大地降低,微细粒子剂量增加,原来沉积在L型连接管的大粒子很大一部分被截留在吸入辅助装置当中.结论 驱动器的规格会对吸入气雾剂的体外沉积产生一定的影响,在药品研发的过程中,可根据气雾剂产品的具体特点(溶液型或混悬型,原料药的粒径大小等)进行驱动器的筛选;吸入辅助装置的使用可以提高气雾剂的药物利用率,推荐患者用药时使用.     

新型肺部给药系统-吸入粉雾剂

吸入粉雾剂 (又名粉雾吸入剂、干粉吸入剂、粉雾剂) 是一种新型的肺部给药系统, 具有稳定性好, 不含抛射剂氟里昂等优点, 近年来受到人们的广泛关注。粉雾剂由粉末吸入装置和供吸入用的干粉组成。本文就近年来粉雾剂的研究进展, 包括吸收机制, 粉雾剂品种, 吸入装置, 制备技术和评价特征参数等进行了综述。     

Characteristics of a capsule based dry powder inhaler for the delivery of indacaterol

Abstract

Objective:

To report performance characteristics and robustness of the Breezhaler device, a new capsule based dry powder inhaler (DPI) with low resistance (0.07?cm?H₂O^½/L/min) facilitating high inspiratory flow rates. This device was developed to deliver the novel, inhaled once-daily ultra long-acting β₂-agonist indacaterol, formulated as an inhalation powder in a capsule, and other investigational drugs including NVA237 and QVA149.     

可溶性载体对左旋硫酸沙丁胺醇胶囊型粉雾剂的体外影响

目的：通过对左旋硫酸沙丁胺醇胶囊型粉雾剂可溶性载体的考察,筛选出最佳的载体材料及制备工艺。方法：对于可溶性载体辅料,采用纳米磨与喷雾干燥仪分别制备药物、辅料的颗粒物,测定颗粒的理化性质及肺部有效沉积率。结果：喷雾干燥仪制备后,载体粒径在25.35~52.94 μm之间,其中乳糖外观圆整,粒径为25.35 μm,乳糖的休止角为33.20°,乳糖的含水量最低为0.99%,压缩度为17.68%,有效沉积率为14.21%,符合药典对粉雾剂的要求。结论：喷雾制备的乳糖,其粉体性能良好,是适合左旋沙丁胺醇粉雾剂的载体材料。     

Identical efficacy of terbutaline multidose dry powder inhaler prior to and after 4 weeks of use by asthmatic patients

We investigated whether the terbutaline multidose dry powder inhaler (Turbuhaler) has the same efficacy after routine daily use as it has when new. Thirty-three adult asthmatic patients were tested on two occasions. The bronchodilatory effect of inhalations of 0.5, 0.5 and 1.0 mg terbutaline at 40-min intervals from the same device was determined prior to and after using the device at least three times a day for 4 weeks. When tested for the second time, 116–186 doses had been inhaled.Although baseline forced expiratory volume in 1 s (FEV₁) was slightly higher after the 4-week treatment period, the bronchodilatory effect of the inhaled terbutaline doses was identical.We conclude that the multidose dry powder inhaler is as effective in delivering terbutaline after a period of routine daily use as it is when new.     

沙美特罗替卡松干粉吸入剂治疗咳嗽变异性哮喘的疗效观察

目的观察沙美特罗替卡松干粉（舒利迭）吸入剂治疗咳嗽变异性哮喘（cough variant asthma,CVA）患者的临床疗效。方法 32例CVA给予舒利迭（沙美特罗/替卡松50μg/250μg）吸入治疗8周后的咳嗽变化情况及肺功能改善情况。结果患者咳嗽严重程度持续下降,症状改善迅速,昼夜呼气峰值流速变异率≤20%,差异有统计学意义（P〈0.05）。结论舒利迭吸入剂可快速有效改善CVA患者症状,应用方便安全。     

Use of mometasone furoate administered via a dry powder inhaler in the treatment of asthma

Abstract

Background:

Inhaled corticosteroids (ICSs) are effective controller medications that treat the chronic inflammation of asthma. The goal of asthma treatment is to improve lung function, symptoms, and the ability to perform daily activities, while decreasing the risk of exacerbations. Mometasone furoate delivered via a dry powder inhaler (MF-DPI) is indicated for once-daily maintenance treatment of asthma in patients as young as 4 years old.     

Terbutaline aerosol from a metered dose inhaler via a 750 ml spacer

Summary The effect on large and small airways of a pressurized terbutaline aerosol delivered via a 750 ml spacer, or via an ordinary actuator, was investigated in a double-blind study of 15 patients with reversible obstructive airflow disease. There was significant bronchodilatation with both devices as measured byRaw, FEV_1.0, PEFR, MEF₇₅, MEF₅₀, and MEF₂₅.Raw showed, a significant difference in favour of the 750 ml spacer. Measurement of Closing Volume (CV) revealed a significant decrease with the spacer, but with the ordinary actuator there was a slight increase in CV; the difference between the devices was significant. The quotient Closing Volume/Vital Capacity (CV/VC%) was significantly decreased with the 750 ml spacer but not with the ordinary actuator. The decrease in volume of isoflow (Viso ) was more pronounced with the spacer but not significantly so. The results suggest that use of a 750 ml spacer may promote more extensive peripheral deposition of the drug in the bronchial tract.     

Dose-response to salbutamol via a novel palm sized nebuliser (Aerodose Inhaler), conventional nebuliser (Pari LC Plus) and metered dose inhaler (Ventolin Evohaler) in moderate to severe asthmatics

AIMS: The Aerodose inhaler is a novel, palm-sized, breath actuated device which requires little patient coordination. This study compared the dose-response of salbutamol delivered by the Aerodose Inhaler (Aerogen Inc., Mountain View, USA) vs Pari LC Plus jet nebulizer (Pari LC Plus; Pari GmbH, Starnberg, Germany) and Ventolin Evohaler HFA pMDI (Evohaler; Allen & Hanburys [GlaxoSmithkline], Uxbridge, UK). METHODS: Twenty-two moderate to severe asthmatic patients, mean (s.d.) age: 44.7 (9.4), FEV(1): 58.1 (12.0), received 4 cumulative doubling doses of salbutamol in a randomised, investigator blind, balanced crossover design. Spirometry and systemic safety variables (heart rate, blood pressure, T wave amplitude, QTc interval and potassium) were measured at baseline and after each dose. RESULTS: Parallel regression analysis revealed that microgram relative potency ratios for the Aerodose Inhaler to be five times more efficient for FEV(1) than either the Pari LC Plus (0.202, 90% CI: 0.189-0.216) or the Evohaler (0.202, 90% CI: 0.189-0.216), while there was no difference between Pari LC Plus vs Evohaler. Similarly, Aerodose Inhaler vs. Pari LC Plus showed approximately five-fold greater potency for all systemic parameters, except blood pressure. As compared to the Evohaler, Aerodose Inhaler had equivalent potency for plasma potassium and T wave amplitude, but demonstrated greater potency for heart rate and QT(c) interval. CONCLUSIONS: This study has indicated therefore, that Aerodose Inhaler is approximately five times as efficient as the Pari LC Plus and Evohaler in relative lung delivery of salbutamol in moderate to severe asthmatics.     

A comparison of the bronchodilatory effect of 50 and 100 μg salbutamol via Turbuhaler® and 100 μg salbutamol via pressurized metered dose inhaler in children with stable asthma

Aim: The aim of the study was to compare the efficacy of single doses of salbutamol Turbuhaler® (50 and 100 μg), salbutamol pressurized metered dose inhaler (pMDI) (100 μg) and placebo in children with stable chronic reversible airway obstruction. Primary efficacy variable (FEV₁-av) was calculated as the area under the curve of forced expiratory volume in one second (FEV₁) (AUC, 0–4 h) and divided by the observed time. Design: The study was of a randomized, single-dose, crossover and double-blind design. Seven centres participated. FEV₁ was measured pre-dose and at 15 min, 0.5, 1, 1.5, 2, 3 and 4 h post study dose. Patients: Forty asthmatic children (9 girls) with a mean age of 9 years (range: 6–12), mean FEV₁ of 1.6 l (range: 0.9–2.4) and a mean FEV₁ in percentage of predicted normal value of 80% (range: 61–109) were randomized into the study. The mean reversibility 30 min after inhaling 2×100 μg salbutamol from pMDI was 20% (range: 9–45) or 15% (range: 8–27) in percentage of predicted normal value. Results: The mean FEV₁-av was 1.63 l for placebo, 1.71 l for 50 μg salbutamol Turbuhaler, 1.76 l for 100 μg salbutamol Turbuhaler and 1.76 for 100 μg salbutamol pMDI. Corresponding values for maximum FEV₁ were 1.76, 1.85, 1.87 and 1.87 l, respectively. There were no statistically significant differences between the active treatments in FEV₁-av or maximum FEV₁. All active treatments were significantly better than placebo. Conclusion: No significant differences in bronchodilating effect between 50, 100 μg salbutamol Turbuhaler and 100 μg salbutamol pMDI in children, aged 6–12 years, with stable asthma could be demonstrated. All active treatments were significantly better than placebo.     

Equivalent lung deposition of budesonide in vivo: a comparison of dry powder inhalers using a pharmacokinetic method

AIMS: The aim of this study was to compare lung deposition of budesonide administered from two dry powder inhalers, Giona Easyhaler 200 microg/dose and Pulmicort Turbuhaler 200 microg/dose by utilizing a pharmacokinetic method. METHODS: This was an open, randomized, crossover study in 33 healthy subjects. The study consisted of four treatment periods separated by at least 4 wash-out days. Equivalence in lung deposition was assessed after a single inhaled 1000 microg (5 x 200 microg) dose of budesonide from Giona Easyhaler and from Pulmicort Turbuhaler. Concomitant oral charcoal administration (40 g) was used to prevent gastrointestinal (GI) absorption of budesonide. The efficacy of the charcoal was studied after oral administration of a budesonide 2 mg capsule. The subjects were trained to inhale the study drugs with controlled flow rates, which resulted in an equal pressure drop (4 kPa) across both inhalers. Venous blood samples for the determination of budesonide concentrations in plasma were drawn before and at predetermined time points up to 8 h after drug administration. Budesonide concentrations in plasma were determined using liquid chromatography-tandem mass spectrometry. Several pharmacokinetic parameters were estimated, the area under the budesonide concentration in plasma vs time curve from dosing to infinity (AUC(0, infinity)) being the primary response variable. Equivalence in lung deposition was concluded if the 90% confidence interval (CI) for the Easyhaler : Turbuhaler ratio of AUC(0, infinity) fell within the limits of 0.8-1.25. RESULTS: The mean AUC(0,infinity) value after Easyhaler treatment was 3.48 (standard deviation (SD) 0.93) ng ml(-1) h and after Turbuhaler treatment 3.46 (1.13) ng ml(-1) h. The Easyhaler : Turbuhaler AUC(0, infinity) ratio was 1.02 and the 90% CI was from 0.96 to 1.09. The mean C(max) values (SD) for budesonide in plasma after Easyhaler and Turbuhaler treatments were 1.22 (0.41) ng ml(-1) and 1.29 (0.44) ng ml(-1), respectively. There was no statistically significant difference (P = 0.39) between the median t(max) for Easyhaler (30 min) and Turbuhaler treatment (23 min). Charcoal impaired the GI absorption of budesonide by 96%. The occurrence of adverse events was similar during both treatments. CONCLUSIONS: The results show that the lung deposition of budesonide from Giona Easyhaler 200 microg/dose and Pulmicort Turbuhaler 200 microg/dose dry powder inhalers is equivalent. The charcoal block used to prevent GI absorption of swallowed budesonide was found to be effective.