Implementing the AIM concept

For orally inhaled drug products (OIPs), aerodynamic particle size distribution (APSD), as an in vitro indication of likely deposition behavior within the lung, is a critical quality attribute. However, the productivity of multistage cascade impaction, the established method for APSD determination, is low. The current economic and regulatory environment has stimulated interest in abbreviated impactor measurement (AIM) methods that characterize the emitted dose using just two size contributions– coarse or large particle mass (CPM or LPM) and fine or small particle mass (FPM or SPM)–allowing for much higher productivity and better decision making based on mutually independent metrics instead of stage groupings from full resolution systems.