A large gap exists between the relatively straightforward robust methods in the pharmacopeias, developed primarily for product release, and the more elaborate approaches to assist in understanding how inhalers are likely to perform in the hands of the patient or caregiver. The authors propose that there is a middle way forward and believe it is possible to retain robustness in methodologies, while achieving significant gains in clinical realism.
Rather than simply separating methodologies into pharmacopeial and clinically relevant groupings, the ways that OIPs can be tested have been divided into three separate streams: a) existing quality control methods in the pharmacopeial compendia, b) augmented quality control methods aiming to improve clinical realism and c) procedures involving further enhancements to optimize clinical relevance. In addition, the authors have broken down each category into the following attributes that help define the scope of each approach: 1) method capability, 2) applicability, 3) regulatory considerations, 4) management considerations and 5) analytical considerations.