Background: Quality by Design (QbD) is an approach encouraged by regulatory bodies and applied by pharmaceutical industries to improve the quality of the final product. The objective of this paper is to describe via a QbD approach the available knowledge on the formulation and manufacturing of solid lipid nanoparticles (SLN) for ocular applications using hot high pressure homogeniser (HPH).
Methods: The formulation of SLN for the ocular delivery of a hydrophilic peptide is discussed based on a QbD perspective, where the knowledge is gathered from literature references.
Results: The Quality Target Product Profile (QTPP) is defined, followed by a description of the Critical Quality Attributes (CQA) and Critical Material Attributes (CMA). After having described the manufacturing process via hot HPH, the Critical Process Parameters (CPP) are discussed along with the possible control strategies.
Conclusions: The QbD approach for the development of a SLN for ocular application described in this review paper can be used as starting point for similar applications.