Issue link: https://www.e-digitaleditions.com/i/1509606
In 2020 and 2021, Inhalation published three articles by the Cascade Impaction Working Group of the International Pharmaceutical Aerosol Consortium for Regulation and Science (IPAC-RS): (1) The liability of fine particle dose (FPD); (2) Cascade impactor stage groupings: Poor decisions from degraded data; and (3) Efficient data analysis (EDA): Size, mass and common sense. In this interview, one of the authors, Adrian Goodey, talks about reactions to the articles in the inhaler community since their publication. 10 OctOber 2023 Inhalation Limitations of metrics used in the regulation of aerodynamic particle size distributions (APSDs) of orally inhaled products (OIPs) An interview with Adrian Goodey of the IPAC-RS Cascade Impaction Working Group on reactions in the inhaler community to a series of published articles In 2020 and 2021, Inhalation published a three-part series of articles by the Cascade Impaction Working Group of the International Pharmaceutical Aerosol Consortium for Regulation and Science (IPAC-RS), written by authors Adrian Goodey, Jolyon Mitchell, Bill Doub, Dave Christopher and Ian Carter: • e liability of fine particle dose (FPD) • Cascade impactor stage groupings: Poor decisions from degraded data • Efficient data analysis (EDA): Size, mass and common sense e first and second articles discussed limitations of metrics commonly used in the regulation of aerody- namic particle size distributions (APSDs) of orally inhaled products (OIPs). e third article proposed using independent assessment of the dimensions of APSD (size and mass) by Efficient Data Analysis. e articles were written to educate, dispel common misconceptions, raise awareness of risks and encour- age scientists to scrutinize current practices. In this interview, Inhalation talks with author Adrian Goodey about reactions to the articles in the inhaler community since their publication. Vicki Schuman, Editor and Publisher, Inhalation: The second article in the series exposed some significant problems with stage groupings, a common regulatory request for aerodynamic particle size distribution (APSD) control. What sort of reaction has this work precipitated since its original publication in August of 2020? Adrian Goodey: Overall, we've been really pleased with the reaction to this article, as well as the other two articles in the series. When we discuss our find- ings with other scientists in the field, they're clearly somewhat shocked at first, and that usually prompts genuine interest. Once they understand the limita- tions of Stage Groupings and Fine Particle Dose, and how poor they are at discriminating between different APSDs, they want to know why they are still being asked to use these metrics. None of us like doing things that don't make sense to us, especially when you consider the investment made in cascade impac- tion testing and the importance of batch-disposition decisions. So, I'd say we have had a lot of positive feedback from our peers and that's always rewarding. We've also gained some interest from health authori- ties and pharmacopeial organizations. At least, we've opened dialogues with a couple of groups, and their initial responses have been relatively promising. In general, whenever we've had the chance to discuss the work with our regulatory and/or pharmacopeial partners, they're quick to understand the problem