Improvement of asthma therapy by a novel budesonide multidose dry powder inhaler

The objective of the present post-marketing surveillance (PMS) was the evaluation of efficacy, tolerability and acceptance of the novel budesonide (CAS 51333-22-3) multidose dry powder inhaler (MDPI) Novopulmon 200 Novolizer. A total of 3,057 patients suffering from allergic, non-allergic or mixed bronchial asthma were included in the PMS. The study medication was administered by inhalation at a median dosage of 2 x 200 micrograms budesonide/day. In order to evaluate the efficacy of the novel budesonide MDPI, pulmonary functions (peak expiratory flow rate (PEFR) and FEV1) were measured at the start of the treatment and after 4 weeks of treatment. Severity of the following symptoms was evaluated on a four-score scale: cough, wheezing, diurnal dyspnea, nocturnal dyspnea and dyspnea on physical effort. Furthermore, the patients' satisfaction in dealing with the control mechanisms (optical, acoustic, sensory, dose counter, overdose prevention) of this innovative MDPI was assessed. Patients who already had used another inhalation system assessed the control mechanisms of the novel budesonide MDPI in comparison with their previous inhalation system (e.g. fluticasone premetered dose MDPI, non-refillable budesonide MDPI). The patients' compliance and any improvement of compliance by the control mechanisms according to physicians' assessments were evaluated. The novel budesonide MDPI was shown to lead to a decrease in the severity of symptoms. The median total symptom score (0 = no symptoms, 15 = all symptoms severe) decreased from 8 before therapy to 2 after therapy. Pulmonary function measurements supported a relief of the patients' symptoms: The median PEFR increased from 5 l/s before therapy to 6.3 l/s at the end of therapy, with a median individual increase of 1 l/s. The median FEV1 increased from 2250 ml before therapy to 2700 ml at the end of therapy, with a median individual increase of 310 ml. The majority of patients were satisfied with the control mechanisms. 97% of the patients were satisfied with the optical control mechanism, 94% with the acoustic, 78% with the sensory mechanism, 92% with the dose counter and 81% with the overdose prevention. Compliance was assessed by the physicians to be good in 84% of the patients, to be satisfactory in 14% and to be not satisfactory in 2%. An improvement in compliance by the control mechanisms of the inhaler was observed in 80% of the patients. 97% of the patients were satisfied with the control mechanisms, the optical and acoustic mechanisms were confirmed as being the most important ones. The vast majority of patients assessed the control mechanisms of the novel MDPI to be better or much better than those of a previously used inhaler (e.g. 41.2% and 52.1%, respectively, of patients who had previously used a non-refillable budesonide MDPI; 38.7% and 44.7%, respectively, of patients who had previously used a fluticasone premetered dose MDPI). Overall, the novel budesonide MDPI was shown to be efficient in the relief of asthma symptoms and improvement of lung function. The MDPI's control mechanisms were shown to be well accepted by the patients and considered by the physicians as an important contributor to an improvement of patient compliance.     

Improvement of asthma therapy by a novel formoterol multidose dry powder inhaler

The objective of this post-marketing surveillance (PMS) was the evaluation of efficacy, tolerability, and acceptance of the advanced formoterol (CAS 73573-87-2) multidose dry powder inhaler (MDPI) Formatris 6 microg/12 microg Novolizer (FN) in asthmatic patients (n = 5219) in a real-life setting. A total of 2727 patients (52%) received concomitant anti-inflammatory treatment exclusively via a budesonide Novolizer (BN). Efficacy of the FN was assessed by measurement of peak expiratory flow (PEF) and forced expiratory volume in one second (FEV1) before and after 4 weeks of therapy. The severity of cough, wheezing, diurnal dyspnea, nocturnal dyspnea and dyspnea on physical effort were assessed on a four-point scale, and a severity sum score was calculated. The patients' satisfaction with the multiple feedback mechanisms, handling and safety of the FN was also assessed. The physicians judged the patient compliance and any improved inhalation reassurance due to FN control mechanisms in comparison with other inhalation systems. FN use (n = 2727) was associated with improved lung function. After 4 weeks, PEF increased by 26% (from 270 L/min to 340 L/min) and the median FEV1 increased by 24% (from 2.1 L to 2.6 L). The median severity sum score decreased from 8.0 before therapy to 3.0 after therapy. Most patients assessed the control mechanisms and safety functions of the FN as 'very good' or 'good'. 96% of patients were satisfied with the optical control mechanism, 92% with the acoustic mechanism, 70% with the taste feedback, 89% with the dose counter and 76% with the overdose prevention. The majority of patients (95%) confirmed that the multiple feedback mechanisms reassured correct drug intake, with 83% rating the FN as 'much better' or 'better' than previously used inhalers. The physicians confirmed that in contrast to previously used inhalers the FN ensured correct inhalation in 87% of all patients. The physicians were satisfied with the patients' compliance in 95% of cases. Finally, the majority of patients (98%) were highly satisfied with the correct inhalation feedback mechanism. 94% of patients intended to continue FN therapy beyond the study. Overall, FN reduced the patients' asthma symptoms and improved lung function, possibly due to improved compliance with therapy. The correct inhalation feedback mechanisms and safety functions of the device were assessed very positively by patients and were considered by the physicians to be important in improving inhalation reassurance and patient compliance.     

Airmax: a multi-dose dry powder inhaler

Airmax is a multi-dose dry powder inhaler. An internal pump measures out the drug dose using controlled air pressure. Inhalation transports the drug into a cyclone separator (where active drug is separated from the lactose carrier) and then into the patient airway. In vitro studies indicate that Airmax may be less dependent on airflow than Turbuhaler for drug delivery; greater dose consistency was seen with administration of budesonide via Airmax than via Turbuhaler. At a low flow rate, the lung deposition of budesonide administered via Airmax was greater than that of budesonide administered via Turbuhaler or a pressurised metered dose inhaler in patients with asthma. In cumulative-dose studies, the mean forced expiratory volume in 1 second (FEV(1)) achieved with salbutamol (albuterol) or formoterol administered via Airmax was equivalent to that achieved with twice the dose administered via dry powder inhalers. black triangle In randomised, double-blind studies, budesonide administration via Airmax was equivalent to administration via Turbuhaler with regards to FEV(1) and improvement in asthma symptoms in both adults and children with asthma. The concentration of adenosine monophosphate producing a 20% fall in FEV(1) increased from pretreatment levels by a greater extent with budesonide administered via Airmax, compared with Turbuhaler. Both adults and children preferred Airmax to Turbuhaler, and more found Airmax easier to use. In one study, the majority of children found learning how to use Airmax trade mark easier than learning how to use Turbuhaler.     

Air classifier technology (ACT) in dry powder inhalation Part 4. Performance of air classifier technology in the Novolizer multi-dose dry powder inhaler

In this study, the in vitro fine particle deposition from a multi dose dry powder inhaler (Novolizer) with air classifier technology has been investigated. It is shown that different target values for the fine particle fraction (fpf<5 microm) of the same drug can be achieved in a well-controlled way. This is particularly relevant to the application of generic formulations in the inhaler. The well-controlled and predictable fpf is achieved through dispersion of different types of formulations in exactly the same classifier concept. On the other hand, it is shown that air classifier-based inhalers are less sensitive to the carrier surface and bulk properties than competitive inhalers like the Diskus. For 10 randomly selected lactose carriers for inhalation from four different suppliers, the budesonide fpf (at 4 kPa) from the Novolizer varied between 30 and 46% (of the measured dose; R.S.D.=14.2%), whereas the extremes in fpf from the Diskus dpi were 7 and 44% (R.S.D.=56.2%) for the same formulations. The fpf from a classifier-based inhaler appears to be less dependent of the amount of lactose (carrier) fines (<15 microm) in the mixture too. Classifier-based inhalers perform best with coarse carriers that have relatively wide size distributions (e.g. 50-350 microm) and surface discontinuities inside which drug particles can find shelter from press-on forces during mixing. Coarse carrier fractions have good flow properties, which increases the dose measuring accuracy and reproducibility. The fpf from the Novolizer increases with increasing pressure drop across the device. On theoretical grounds, it can be argued that this yields a more reproducible therapy, because it compensates for a shift in deposition to larger airways when the flow rate is increased. Support for this reasoning based on lung deposition modelling studies has been found in a scintigraphic study with the Novolizer. Finally, it is shown that this inhaler produces a finer aerosol than competitor devices, within the fpf<5 microm, subfractions of particles (e.g. <1, 1-2, 2-3, 3-4 and 4-5 microm) are higher.     

The development of a novel dry powder inhaler

A novel active and multi-dose dry powder inhaler (DPI) was developed and evaluated to deliver a small quantity (100-500 μg) of pure drug without any excipient. This dry powder inhaler utilized two compressed air flows to dispense and deliver drug powder: the primary flow aerosolizes the drug powder from its pocket and the secondary flow further disperses the aerosol. In vitro tests by Anderson Cascade Impactor (ACI) indicated that the fine particle fraction (FPF) (<4.7 μm) of drug delivery could reach over a range of 50-70% (w/w). Emitted dose tests showed that delivery efficiency was above 85% and its relative standard deviation (RSD) was under 10%. Confocal microscopy was used to confirm the deposition of fluorescently labeled spray-dried powder in rabbit lungs. Also, a chromatographic method was used to quantify drug deposition. The results of animal tests showed that 57% of aerosol deposited in the rabbit lung and 24% deposited in its trachea. All the results implied that this novel active dry powder inhaler could efficiently deliver a small quantity of fine drug particles into the lung with quite high fine particle fraction.     

Novel dry powder inhaler particle-dispersion systems

Dry powder inhalers are a diverse family of devices that have emerged as a rapidly growing segment of the respiratory therapeutics area. The forces that these devices must impart into dry powder formulations for effective dispersion performance and reproducibility of delivery are relatively large, and multiple mechanisms have been developed in attempts to improve the efficiency of these systems. In this review, we address the reasons for the proliferation of dry powder inhalers, beginning with an abbreviated introduction on the basic inter-particulate forces that need to be disrupted to achieve successful powder dispersion and effective lung delivery. From this background, we survey the diversity of inhaler designs, starting from marketed devices, before introducing some of the novel device designs under development, both patient driven (passive) and device driven (active), as we attempt to link the themes of the device design features to the present understanding of the dynamics governing powder dispersion. Finally, we conclude by providing some assessment on the future of the wide range of device designs and mechanisms that have evolved by considering technical, regulatory and market forces.     

Air classifier technology (ACT) in dry powder inhalation Part 3. Design and development of an air classifier family for the Novolizer multi-dose dry powder inhaler

In this study, the design of a multifarious classifier family for different applications is described. The main design and development steps are presented as well as some special techniques that have been applied to achieve preset objectives. It is shown by increasing the number of air supply channels to the classifier chamber (from 2 to 8), that the fine particle losses from adhesion onto the classifier walls can be reduced from 75% to less than 5% of the real dose for soft (spherical) agglomerates. By applying a bypass flow that is arranged as a co-axial sheath of clean air around the aerosol cloud from the classifier, the airflow resistance of the classifier can be controlled over a relatively wide range of values (0.023-0.041 kPa(0.5) min l(-1)). This, without affecting the fine particle dose or increasing the fine particle losses in the inhaler. Moreover, the sheath flow can be modelled to reduce the depositions in the induction port to the cascade impactor or in the patient's mouth, which are the result of back flows in these regions. The principle of powder induced pressure drop reduction across a classifier enables assessment of the amount of powder in the classifier at any moment during inhalation, from which classifier loading (from the dose system) and discharge rates can be derived. This principle has been applied to study the residence time of a dose in the classifier as function of the carrier size fraction and the flow rate. It has been found that this residence time can be controlled in order to obtain an optimal balance between the generated fine particle fraction and the inhalation manoeuvre of the patient. A residence time between 0.5 and 2 s at 60 l/min is considered favourable, as this yields a high fine particle dose (depending on the type of formulation used) and leaves sufficient inhaled volume for particle transport into the deep lung.     

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.     

Peak inspiratory flow rates generated through the Novolizer and the Turbuhaler dry powder inhaler devices by children with stable asthma.

We compared the peak inspiratory flows (PIF) generated through a novel dry powder inhaler device, the Novolizer (PIF-N), and the Turbuhaler (PIF-T). Forty-six pediatric patients with stable bronchial asthma were randomized in an open-label, multicenter, crossover trial. No drug was administered during the inhalation maneuvers that were spaced by 10 min. There was neither a carryover nor a sequence effect. The patients were characterized by mean age of 8.5 years, mean FEV(1) of 1.79 L, and mean PIF without any device (baseline, PIF-B) of 185 L/min. Through the devices mean PIF-N of 94 L/min and mean PIF-T of 69 L/min were achieved, calculated from the maxima of three inhalations. This resulted in p < 0.0001 for the difference. The median PIFN/PIF-T ratio was estimated as 1.39. Each child achieved a higher PIF-N than PIF-T and was able to release the feedback mechanisms of the Novolizer indicating sufficient inhalation performance. We conclude that the PIF through the Novolizer is higher than the PIF through the Turbuhaler in stable asthmatic children. The flow rates achieved through the Novolizer allow for sufficient lung deposition even in children as young as 6 years.     

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.     

Experimental observations of dry powder inhaler dose fluidisation

Dry powder inhalers (DPIs) are widely used to deliver respiratory medication as a fine powder. This study investigates the physical mechanism of DPI operation, assessing the effects of geometry, inhalation and powder type on dose fluidisation. Patient inhalation through an idealised DPI was simulated as a linearly increasing pressure drop across three powder dose reservoir geometries permitting an analysis of shear and normal forces on dose evacuation. Pressure drop gradients of 3.3, 10 and 30 kPa s(-1)were applied to four powder types (glass, aluminium, and lactose 6 and 16% fines) and high speed video of each powder dose fluidisation was recorded and quantitatively analysed. Two distinct mechanisms are identified, labelled 'fracture' and 'erosion'. 'Fracture' mode occurs when the initial evacuation occurs in several large agglomerates whilst 'erosion' mode occurs gradually, with successive layers being evacuated by the high speed gas flow at the bed/gas interface. The mechanism depends on the powder type, and is independent of the reservoir geometries or pressure drop gradients tested. Both lactose powders exhibit fracture characteristics, while aluminium and glass powders fluidise as an erosion. Further analysis of the four powder types by an annular shear cell showed that the fluidisation mechanism cannot be predicted using bulk powder properties.     

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.     

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.     

A dry powder inhaler with reduced mouth-throat deposition.

A novel, compact, and highly efficient dry powder inhaler (DPI) with low mouth-throat deposition is described. The performance of this DPI was evaluated by measuring both (1) the total aerosol deposition in and distal to an idealized mouth-throat cast and (2) the fine particle fraction (FPF) using a standard Mark II Anderson impactor. Ultraviolet (UV) spectroscopy techniques were used in the aerosol deposition measurements. Two inhalation aerosol powders, namely budesonide (extracted from a Pulmicort/Turbuhaler multi-dose device, 200 microg/dose) and ciprofloxacin + lipid + lactose (in-house), were dispersed by the DPI at a steady inhalation flow rate of 60 L/min. The newly developed DPI had a total aerosol delivery distal to the mouth-throat cast of 50.5% +/- 3.04% and 69.7% +/- 1.5% for the budesonide and ciprofloxacin + lipid + lactose aerosols, respectively. This is a significant improvement over the Turbuhaler original device delivery of 34.5% +/- 5.2%, particularly considering that in vitro mouth-throat deposition dropped from 27.5% +/- 5.4% with the budesonide Turbuhaler to 11.0% +/- 3.5% with the present inhaler. The different lung deliveries from the same inhaler for the two formulations above also confirm that the overall performance of an inhaler is optimizable via powder formulations.     

Development of liposomal amphotericin B dry powder inhaler formulation

The purpose of our study was to prepare and optimize liposomal Amphotericin B (AMB) dry powder inhaler (DPI) formulation for treatment of invasive lung fungal infection. Liposomes were prepared by reverse phase evaporation technique using ethyl acetate and ethanol (1:1) as organic solvents to avoid a possible risk for human health and to impart adequate stability of the vesicles. Drug lipid ratio was 1:10 with membrane composition of hydrogenated soyaphosphatidylcholine; cholesterol and either saturated soyaphosphatidylglycerol (7:3:0.5) or stearylamine (1:1:0.1) was used to prepare negatively (AMB1) and positively (AMB2) charged liposomes, respectively. Liposomes were extruded through 2 microm polycarbonate membrane, separated from unentrapped drug and subjected to lyophilization using Tris buffer containing cryoprotectants in various mass ratios. Sucrose was found to be the best cryoprotectant for liposomal AMB in a mass ratio of lipid: sucrose at 1:5 for AMB1 and AMB2, respectively. Sorbolac 400 and sieved Pharmatose 325 M (500#) in varying mass ratios were used as carriers to prepare the liposomal DPI formulations and subjected to determination of angle of repose, compressibility index, dispersiblity index, water content, scanning electron microscopy, and fine particle fraction (FPF). Carrier blend of Sorbolac 400 and 10% sieved Pharmatose 325 M (liposome: carrier ratio to be 1:6) resulted in 22.6 +/- 2.2% and 16.8 +/- 2.2% FPF for AMB1 and AMB2, respectively with significantly different (p >.05) device fraction. Percent dug retention studies were conducted at different storage conditions and demonstrated a shelf life over 1 year at refrigerated storage condition (2-8 degrees C).     

Pulmonary disposition of budesonide from liposomal dry powder inhaler

The Purpose of this study was to establish the use of a developed dry powder inhaler of budesonide liposomes in pulmonary drug delivery. Budesonide liposomes composed of egg phosphatidyl choline (EPC) and cholesterol were prepared using a lipid-film hydration technique. The liposomal dispersion was freeze dried and formulated to a dry powder inhaler. The entrapped drug values (91.79% to 78.99%) of freeze dried liposomes were estimated in prepared batches after purification from the free drug by centrifugation of the rehydrated vesicles. In vitro drug retention was evaluated using methanolic phosphate buffer saline and bronchoalveolar lavage, following incubation at 37 degrees C. All batches were found to retain more than 63.54% of budesonide within liposomes at the end of 24 h. Rehydrated budesonide liposomes or nonencapsulated budesonide was delivered to rat lungs by intratracheal administration. The pulmonary drug disposition was assessed by simultaneous monitoring of drug levels in the bronchoalveolar lavage and lung tissue. After intratracheal administration, cumulative drug levels in the lung tissue indicated that the targeting factor was at least 1.66 times higher in liposomes. The maximal drug concentration in the lung homogenate for the liposomal dry powder inhaler was 36.64 micrograms as compared to 78.56 micrograms with the plain drug. Similarly, the time for maximum drug concentration in the lung homogenate for the liposomal dry powder inhaler was 9-12 h as compared to 3 h for that of the plain drug. Hence, the use of a developed liposomal budesonide dry powder inhaler was found to provide desired drug levels in the lungs for a prolonged period of time, which is expected to enhance the therapeutic index of the drug and probably reduce the dose and cost of therapy as well.     

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。     

Methacholine dry powder inhaler as a new tool for bronchial challenge test

BACKGROUND: The methacholine (MCH) challenge test is performed to detect bronchial hyperresponsiveness in subjects suffering from asthma. It is conducted by inhaling spasmogen substances at increasing doses and measuring FEV1-PD20 variation following the bronchoconstriction evoked. AIM: This paper describes a new method for MCH challenge test using pre-metered respirable powders of MCH at different doses for facilitating test execution. The availability of a series of pre-metered doses gives higher control over aerosolized dose and fine particle fraction (respirable dose), improving the accuracy and repeatability of the test. Dosimetric tests with MCH solution and pre-dosed powder challenge tests were clinically compared. METHODS AND MATERIALS: The inhalation powders were prepared by spray drying of solutions of methacholine, mannitol and hydroxypropylmethylcellulose in which different concentrations of MCH were included. The methacholine powders prepared were carefully characterized in terms of aerodynamic properties. RESULTS: Inhalation powders containing methacholine from 12.5 to 200 microg per metered dose, having a fine particle fraction between 40 and 60%, were prepared using mannitol and cellulose polymer. Eighteen subjects (12 hyperresponsive and six normal) were subjected to both the MCH solution and powder tests in random sequence. No significant differences in FEV1 and PD20 values were found between the challenge tests performed with liquid and powder formulations of methacholine. CONCLUSIONS: Powders of MCH having high respirability of the delivered doses can be prepared by spray drying. They allow for the performance of a challenge test using a dry powder inhaler. The powder dose series can be an alternative to the current dosimetric test with MCH solutions.