Arming the airways: an update on the clinical status of intranasal vaccines & the role of mucosal adjuvants
Vaccine Insights 2023; 2(6), 213–228
10.18609/vac.2023.033
The COVID-19 pandemic highlighted the need for mucosal vaccines capable of reducing viral transmission as well as disease severity. As such, there are an unprecedented number of intranasal vaccines undergoing clinical testing. Due to their scalability and cost-effectiveness, viral vectors dominate the intranasal vaccine clinical trial landscape. However, concerns surrounding safety and pre-existing anti-vector immune responses support the development of other vaccine technologies. Subunit vaccines are one such strategy, given their targeted approach and capacity for tailoring via selection of appropriate adjuvants. One limitation, however, is the lack of safe and effective mucosal adjuvants. This review outlines the current progress in clinical research of intranasal vaccines with a focus on mucosal adjuvants. Given the ongoing impact of respiratory pathogens, it is imperative that the current momentum for the development of mucosal vaccines continues and is broadened to include diseases beyond COVID-19.