Chapter 4 - Clinical Impact and Patient Safety: The Potential of Microneedles in Changing the Form and Perception of Transdermal Drug Delivery

Abstract

Transdermal drug delivery offers a number of advantages for the patient, due to not only its noninvasive and convenient nature, but also factors such as avoidance of first-pass metabolism and prevention of gastrointestinal degradation. It has been demonstrated that microneedles can increase the number of compounds amenable to transdermal delivery by penetrating the skin's protective barrier, the stratum corneum, creating a pathway for drug permeation to the dermal tissue below. Microneedles have been extensively investigated for drug and vaccine delivery. The different types of microneedle arrays and their delivery capabilities are discussed in terms of drugs, including biopharmaceutics and vaccines. Patient usage and effects on the skin are also considered. Microneedle research and development are now at the stage where commercialization is a viable possibility. A number of long-term safety questions relating to patient usage will need to be addressed moving forward. Regulatory guidance is awaited to direct the scale-up of the manufacturing process alongside provision of clearer patient instruction for safe and effective use of microneedle devices.