Noninvasive delivery technologies: respiratory delivery of vaccines.

This paper reviews the developments in noninvasive methods of drug delivery, with a focus on the delivery of vaccines via the respiratory tract. Recent results indicate that the respiratory system, and the nasal mucosa in particular, provide a valuable target site for immunisation against respiratory and mucosal pathogens. Vaccine delivery via the nasal and pulmonary routes each present distinct sets of performance requirements. Current delivery systems in development for both routes are reviewed herein. The storage and respiratory delivery of drugs and vaccines in powder form has been shown to provide improved stability and extended retention time in the respiratory mucosa. These features, in addition to the noninvasive nature of respiratory delivery, can provide benefits to public health vaccination campaigns, facilitating mass vaccination without the high cost of maintaining cold-chain storage.