AI Summary & Key Takeaways
AI InsightWhilst the paddle-over-disk method yielded the fastest dissolution rate, it does not mean that it is reflective of in vivo dissolution.
📌 3 Key Takeaways
Abstract
Mimicking the lung environment has always been a challenge with regards to dissolution testing of inhaled drugs from dry powder inhalers (DPIs). The aim of this review is to critically appraise the literature currently available on the in vitro test methods for dissolution of orally inhaled drug particulates. Reasons for the lack of standardised testing methods are discussed. Currently, there is not one test that fully represents the situation that occurs in the lungs in vivo, and this is the reason for the lack of a dissolution test recommendation by the pharmacopoeia. The importance of dose collection as a prerequisite to dissolution testing is also discussed using the Andersen cascade impactor as an example. Moreover, a study was carried out to determine the most robust method for testing the dissolution of fluticasone. Three different testing methods were used, i.e., the Transwell system, the paddle-over-disk method and DissolvIt. The results of this study determined that the paddle-over-disk method had the fastest dissolution rate. However, the data showed that there was a lack of similarity between all three tests. This lack of similarity between dissolution methods contributes to the reason why there is no standardised recommended dissolution method listed in the pharmacopoeia. Whilst the paddle-over-disk method yielded the fastest dissolution rate, it does not mean that it is reflective of in vivo dissolution.