Mixing energy as an adjustment tool for aerodynamic behaviour of an inhaled product: In-vitro and in-vivo effects

This paper describes the development of a fixed dose dry powder combination of indacaterol maleate (Inda) and glycopyrronium bromide (Glyco) in Easyhaler® inhaler for a comparative pharmacokinetic (PK) study, as well as the outcome of such a study. The development aim was to produce formulations with three different in vitro dispersibility profiles for both Inda and Glyco. This so-called 'rake' approach allows for quantitation of the candidate formulations relative to the reference product Ultibro® Breezhaler® in terms of the key PK parameters. Three formulations (A, B and C) were produced based on the mixing energy concept. For both APIs, formulation A (lowest mixing energy) displayed the highest fine particle fractions and formulation C (highest mixing energy) the lowest. GMP manufacturing confirmed the performance of the three formulations. The candidate formulations were tested against the reference product in a single dose PK study in healthy volunteers. Clear differences in Inda plasma concentration profiles were observed between the treatments when administered concomitantly with charcoal, with Easyhaler A showing the highest Cmax value and Easyhaler C the lowest. Easyhaler B was bioequivalent to Ultibro Breezhaler with regard to the primary PK parameters of Inda, Cmax and AUC72h. For Glyco, Easyhaler formulations A, B and C provided lower peak concentrations than Ultibro Breezhaler. For AUC72h of Glyco, Easyhaler B was bioequivalent to the reference product. Additional measures for adjustment of formulation performance can be foreseen, whose effects can be predicted based on mixing energy theory.

Consistent Dosing Through the Salmeterol-Fluticasone Propionate Easyhaler for the Management of Asthma and Chronic Obstructive Pulmonary Disease: Robustness Analysis Across the Easyhaler Lifetime

Background: Easyhaler (registered trademark by Orion Corporation) is a multidose dry powder inhaler (DPI) for the treatment of asthma and chronic obstructive pulmonary disease (COPD), designed to be simple and easy to use. Salmeterol-fluticasone propionate (S-F) Easyhaler (50/250 and 50/500 μg per dose), available in several European countries, provides combined inhaled corticosteroid and long-acting beta agonist therapy for the management of asthma and COPD. A requirement of the European Committee for Medical Products for Human Use guidelines is to demonstrate product performance under conditions that mimic real-life patient use. Therefore, our aims were to assess the robustness of the S-F Easyhaler by assessing the delivered dose (DD) and fine particle dose (FPD) throughout the inhaler lifespan and under simulated environmental stress conditions. Methods: This was a noncomparative exploratory in vitro study. Two batches and six to nine inhalers per batch from both dose strengths were used to assess drug delivery performance over the inhaler lifespan (doses 1-60). For determining the impact of simulated environmental stress (tests for exposure of dropping, vibration, moisture, and freeze-thawing) on DD and FPD, one batch and three inhalers per batch from both dose strengths were used per test, respectively. Aerodynamic particle size distribution was evaluated during the simulated dropping and vibration tests. Results: DD and FPD from both dose strengths of S-F Easyhaler performance remained consistent through the inhaler lifespan and simulated environmental stress did not affect its performance. Similar DD and FPD values were observed with or without dropping, vibration, exposure to moisture, and freeze-thawing, and no inhaler breakages occurred during the simulated tests. Conclusions: The in vitro performance of S-F Easyhaler at both dose strengths suggests that reliable dosing and robustness can be achieved under real-life stress conditions; S-F Easyhaler is a durable DPI for the management of asthma and COPD.