Step-wise approach to developing a scale-independent design space for functional tablet coating process

Abstract

The objective of this study is to present a practical example of a scale-independent design space development using a step-wise approach. A detailed description of the development process with a systematic outline of the main steps is provided. Design space is developed for film coating of tablets with moisture protective polyvinyl alcohol (PVA) based coating. The impact of scale-independent coating process parameters on the properties of film-coated tablets (FCT), i.e. water activity and film coating protection ability, and consequently on product long-term stability is explored. The main finding is that with model simplifications, a step-wise approach and rational development of scale-independent design space for the coating process, it is possible to efficiently predict, control, and optimize the long-term stability of a moisture sensitive product. However, the PVA moisture protective coating itself is recognized as having conflicting effects on product stability.

Keywords:

• Quality by design (QbD)
• design of experiments (DoE)
• design space
• mechanistic modeling
• empirical modeling
• hybrid modeling
• scale-independent parameters
• coating process

Acknowledgements

The authors express special thanks also to Petra Perhavec, Pito Roslansky and all coworkers from Lek Pharmaceuticals d.d. who greatly contributed to this study.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors are thankful to Lek Pharmaceuticals d.d. for financial support and material supplied for this study.