Revising old principles of inhaled treatment in new fixed combinations for asthma

An innovative corticosteroid/long-acting β2-agonist breath-triggered inhaler: facilitating lung delivery of fluticasone propionate/formoterol fumarate for the treatment of asthma

Introduction: Incorrect inhaler technique is one reason why the efficacies of inhaled asthma treatments in clinical trials and effectiveness in the real world differ. Inhaler technique is critical for drug delivery to the lungs; incorrect technique negatively impacts asthma control and long-term outcomes. Breath-triggered inhalers (BTIs) can simplify drug administration and are suitable for most patients, including those with reduced inspiratory flow. Until recently, no inhaled corticosteroid/long-acting β₂-agonist combination BTI was available in Europe. The flutiform® (fluticasone propionate/formoterol fumarate [FP/FORM]) k-haler® is the first combination BTI now approved in Europe for asthma maintenance treatment.Areas covered: We review studies examining the challenges posed to patients by different inhaler types and explore evidence demonstrating the clinical efficacy of FP/FORM administered via a pressurized metered-dose inhaler. We also review the pharmacokinetic/pharmacodynamic studies supporting FP/FORM k-haler use, and consider data showing high lung deposition with the device. Finally, we review patient experiences using the BTI, device characteristics, and health economic aspects.Expert opinion: Despite the availability of therapies, asthma control levels remain low, and there is a clear need for easy-to-use inhalers. Research to increase our understanding of critical errors with each inhaler and how to overcome them is important for improving care.Abbreviations: AUC_t: area under the plasma concentration-time curve from the time of dosing to the last measurable concentration; BDP: beclometasone dipropionate; BTI: breath-triggered inhaler; BUD: budesonide; CI: confidence interval; C_max: maximum observed plasma concentration; DPI: dry powder inhaler; FDC: fixed-dose combination; FEV₁: forced expiratory volume in 1 s; FORM: formoterol fumarate; FP: fluticasone propionate; HCP: health-care professional; ICS: inhaled corticosteroid; LABA: long-acting β₂-agonist; OR: odds ratio; PIL: patient information leaflet; pMDI: pressurized metered-dose inhaler; SAL: salmeterol xinafoate.

Instant velocity and consistency of emitted cloud change by the different levels of canister filling with Metered Dose Inhalers (MDIs), but not with Soft Mist Inhalers (SMIs): a bench study

Background

Inhalation is the preferred route for respiratory drug delivery, but several factors contribute to the variability of the respirable dose fraction. Instant velocity and the dynamic characteristics of the droplet cloud represent crucial factors. Aim was to measure and compare the instant velocity and the consistency of emitted cloud from five different MDIs (A - Salbutamol sulphate 100mcg, GSK; B - Salbutamol sulphate 100mcg, Valeas; C - Salmeterol xinafoate/Fluticasone propionate 25/125mcg, GSK; D - Formoterol fumarate/Bechlomethasone propionate 6/100mcg, Chiesi; E - Formoterol fumarate/Fluticasone dipropionate 5/125mcg, Mundipharma) and one SMI (Tiotropium bromide 5mcg, Boehringer Ingelheim), at different distance from the nozzle and canister filling.

Methods

Measurements were made at 90, 50, and 10% of canister filling, and at 5, 10, and 20 cm from the nozzle, for a total of 972 puffs. A high speed video photography protocol was adopted and high speed cameras (1.200 frames/sec.) were used. Data were acquired by means of specialized softwares. Temperature, humidity, and vibrations occurrence were strictly controlled during measurements. Statistics: Anova and p < 0.05 were accepted as the minimum significance level.

Results

MDIs generated different Instant velocities: MDI B generated the highest, while MDI A the lowest. As expected, velocity decreased in proportion to the distance from the nozzle. Except with MDI C, instant velocity decreased significantly over the first 50% of canister emptying, but dropped by >33% at 90% of emptying with all other MDIs (p < 0–037; p < 0.001; p < 0.005, and p < 0.001, respectively). Instant velocity was extremely lower (p < 0.001) and constant for all levels of canister filling (p = ns) with SMI. All MDIs had a very fast jet phase, ranging 0.01–0.03 s at 10 cm, and 0.03–0.05 s at 20 cm from the nozzle, without any significant difference from each other (p = ns). MDIs generated a cloud similarly tight (p = ns) at 10 and 20 cm from the nozzle, while it was extremely wider and constant with the SMI (p = 0–001). Also the cloud turbulence was minimized during the SMI emission.

Discussion and Conclusions

MDIs are characterized by a substantial variability in both their instant velocity and consistency of the emitted cloud at different levels of canister filling. SMI generates a much slower soft mist cloud which is constantly homogeneous and independent of canister emptying. These peculiarities assessed at bench are suggesting a higher dose consistency and a much more effective therapeutic performance also in real life.

A valid option for asthma control: Clinical evidence on efficacy and safety of fluticasone propionate/formoterol combination in a single inhaler

A good level of asthma control improves the quality of life of asthmatic patients and may prevent future risk in term of exacerbations and decline of pulmonary function. However, in a real-life setting, several factors contribute to generally low compliance to the treatment. A rapid-onset, long-lasting medication with few adverse effects may contribute to improve adherence to therapy, along with an effective patient education and a good physician-patient communication. Many clinical studies demonstrated the comparable efficacy of the new fluticasone propionate/formoterol (FP/F) combination in a single inhaler to other combinations of inhaled corticosteroids and β2agonists and the superiority of FP/F as compared to its individual components. Also the safety profile of this combination was encouraging in all studies, even at higher doses. By effectively and safely targeting both airway inflammation and smooth muscle dysfunction, the two pathological facets of asthma, and allowing the patient to adapt dose strength, FP/F combination in a single device represents a valid option to improve asthma control in patients with different levels of asthma severity.