The match between adhesive mixture powder formulations for inhalation and the inhaler device

The device or the formulation? Which one governs drug dispersibility from the inhaler? To address this question, three budesonide-containing reservoir DPIs: Novopulmon Novolizer®, Giona Easyhaler® and DuoResp Spiromax®, were analyzed using the Next Generation Impactor, NGI. Thereafter, the devices were carefully opened, emptied, and formulations were switched between devices. Finally, three 'prototype' formulations with carriers of different particle size were produced and tested in the Novolizer and Easyhaler devices. Among the DPI products, the two devices which have a flow path with a cyclone-type geometry, i.e., the Novolizer and the Spiromax, yielded a fine particle fraction, FPF, above 40%. The Easyhaler, which has a straight mouthpiece outlet, produced an FPF of 18 %. When the Novopulmon and the DuoResp formulations were assayed in the Easyhaler device, poor fine particle fractions were obtained. To the contrary, the Giona formulation produced a high FPF when tested in the Novolizer device. The results clearly show that the device is the dominating factor to dispersibility for the investigated products. Along the same lines, all three 'prototype' formulations produced high fine particle fractions in the Novolizer device, with the formulation with the largest carrier giving the best performance. Tested in the Easyhaler device, the prototype formulations produced low fine particle fractions, but interestingly, the formulation with the smallest carrier particle size yielded the highest FPF. It can be concluded that there is a link between inhaler design and the effect of carrier particle size, where larger carriers provide better dispersion in cyclone-type devices while smaller carriers seem to be more beneficial for inhalers which has a straight flow path for the powder formulation.

Safety of formoterol after cumulative dosing via Easyhaler and Aerolizer

This randomised, double-blind, double-dummy, cumulative dose, multicentre crossover study aimed to demonstrate non-inferiority in safety of formoterol delivered via Easyhaler versus Aerolizer. The secondary objective was to compare the efficacy of the devices. Thirty-three adult asthmatic subjects entered the study and 32 completed it. The study comprised screening and two study days, with each subject inhaling 96 microg (12, 12, 24 and 48 microg) cumulative dose of formoterol via the study inhalers. Serum potassium (S-K+), vital signs and spirometry were performed at baseline, 1h after each dose and additionally 4h after the last dose. The primary safety variable was S-K+. Secondary safety variables were heart rate, corrected QT interval, blood pressure, serum glucose and adverse events. Spirometry was assessed to evaluate efficacy. The results showed non-inferiority in safety of formoterol inhaled via Easyhaler compared to Aerolizer. The adjusted treatment difference in the S-K+ values after 96 microg cumulative dose of formoterol was 0.14 mmol/L being clearly above the pre-determined lower limit of the non-inferiority criterion of -0.2 mmol/L. There were dose-related changes in secondary efficacy variables after both treatments. The changes were comparable in most of the parameters but heart rate was statistically significantly higher and decrease in diastolic blood pressure greater after formoterol via Aerolizer than that via Easyhaler. The occurrence of adverse events was dose-related, the most common events being tremor, hypokalaemia, headache and palpitation. The spirometry results showed no statistically significant difference in efficacy between the treatments. In conclusion, formoterol delivered via Easyhaler was as safe as via Aerolizer.