Paromita Bakshi, Sarbani Roy, Sayantan Sadhukhan, Sabyasachi Maiti

Abstract

Commonly, the hypodermic needles are used for the vaccination programs, which is important for improving the quality of life. However, needle phobia retracts the patient from vaccinations. Novel vaccination strategies should be cost effective, employ safer injection practices and should evoke sufficient immune responses in patients. The lack of sensory nerve endings and blood vessels in the epidermal layer of skin opens the door for application of the vaccine in painless way. The dermal lymphatic system causes rapid and efficient uptake of biologics. Furthermore, the dermis is particularly rich with lymphatic capillaries and the rate of fluid exchange in the dermis is found very high than any other compartment in the body. Different types of microneedles have been developed for intradermal delivery of drugs/ vaccines. Out of these, self-dissolving polymeric microneedles has shown a great promise in terms of delivery of the biologics. Moreover, the devices were found equally effective in small doses when delivered via intradermal route, compared to others. Needle-free delivery systems could be advantageous in terms of safety and application in mass vaccination programs. This comprehensive review will discuss the recent achievements and scope in the area of polymeric microneedle-based intradermal vaccine delivery systems.