Use of Discrete Element Method to Troubleshoot Aesthetic Defects in Pharmaceutical Tablets

Abstract

Pharmaceutically elegant tablets are an expectation from pharmacists, health care providers and consumers for solid oral dosage forms. The presence of non-aesthetically pleasing defects in solid oral dosage forms can result in complaints back to the manufacturer and potentially non-compliance with medicines. The purpose of this study was to simulate and analyze the design of a tablet core and the aqueous film-coating process, to gain a better understanding of tablet defect generation, and to help eliminate the defects from the finished product. This evaluation employs Discrete Element Method (DEM) using the software product Altair� EDEM� to understand the potential mechanisms that are causing the defects, based on the forces tablets experience in the coating operation, along with the number of tablet-to-tablet interactions that occur during the duration of the process. Defects observed during the scale up of the coating process to a commercial production scale confirmed the DEM results where physical damage was observed more on the edges of the tablets than the face of the tablets. Also based on the number of tablet-to-tablet interactions, operating the coating process under thermodynamically wetter processing conditions can result in elevated levels of picking and sticking defects being observed based on the specific tablet design evaluated. The results of these efforts allowed the manufacturing and development team to evaluate improvement opportunities not only in tablet design but also to re-evaluate the thermodynamic design space of the coating operation and the mechanical set up of the coating equipment.