Three stability studies simulating patient use were performed on aclidinium bromide 400 μg/formoterol fumarate dihydrate 12 μg inhalation powder in the Genuair™* inhaler.
Samples of a development batch representative for commercial production were tested after corresponding pre-storage for 12, 22, and 35 months over an in-use period of 10 weeks, at climatic zone II and IVb conditions.
At day 0 and appropriate time intervals until the final dose was dispensed and the lock-out mechanism of the inhaler was activated, the following parameters were assessed: water content, degradation products, content per cartridge, delivered dose (DD), fine particle dose (FPD) and microbial growth. All results, notably DD and FPD (Figure 1), were within the expected range and well inside the specifications applied during development. More precisely, the mean results of DD for aclidinium bromide were between 370 µg and 451 µg (specification 320–480 µg) and for FPD between 139 µg and 182 µg (specification ≥80µg), while the mean values of DD for formoterol fumarate dihydrate were between 10.1 µg and 13.1 µg (specification 9.6–14.4 µg) and for FPD between 2.5 µg and 3.7 µg (specification ≥1.8 µg).
The studies show that stable pharmaceutical quality can be guaranteed under
in-use conditions for a period longer than the allowed 60 days after unpacking the drug product pre-stored even up to the end of shelf life.
*Registered trademark of AstraZeneca group of companies; for use within the USA as Pressair® and Genuair™ within all other licensed territories.