Vaccine delivery: Beyond needles

Abstract

Vaccines are most commonly administered using a needle and syringe; however, their use is associated with numerous drawbacks such as needlestick injuries to health care workers and the costs and logistical challenges associated with the safe disposal of sharps in the medical waste stream. The seriousness of these issues, the need to simplify global immunization programs, and the development of needle-free vaccine delivery have become a global priority. One needle-free vaccine approach being developed is the use of a vaccine patch which delivers the vaccine through the skin. Referred to as transcutaneous immunization (TCI), the topical application of a vaccine formulation on the skin targets the skin as an immunologically active site. In this chapter, we describe the development of the vaccine patch system and its evaluation in both preclinical and clinical studies. These studies demonstrate that the vaccine patch is a simple to use, needle-free vaccine system which induces robust immune responses. With its ability to be used outside the cold chain, it represents a solution to one of the major challenges facing global health care today.