ABSTRACT
Tablets, liquids, inhalants-transdermals? What exactly are these “skin patches?” Why are they so special? Are they considered the “in medicines” of the last decade? How are they validated?
This chapter will provide an answer to each of these important questions. It will begin by providing a definition of what transdermals are, citing the advantages of these innovative drug types, and the difficulties associated with their manufacture. It will then discuss the basic elements of transdermal validation, breaking the program into manageable “pieces.” The focus will shift to discussing the unit operations required in the manufacture of matrix transdermals. The stage for the main section of this chapter will be set with a discussion of the individual components that must be qualified in support of process validation. Covered as parts of that discussion are the equipment and process qualification steps. The process qualification steps are broken down into real-world activities that support successful process qualification: process development; process ranging studies; scale-up studies, demonstrations, and trials; and process-specific validations. Each of these activities serves to increase confidence and familiarity with the qualification activities. The chapter will then divert and briefly discuss potential problems and resolutions associated with transdermal processes.
