Adjuvants are critical components of vaccines that enhance the host immune response to the vaccine antigen, however, only a small number of adjuvants are used in vaccines approved for human use. This is in part due to the slow process of novel adjuvants advancing from preclinical models to human studies, and modest mechanistic insights obtained using standard immunological methods to justify selection of a particular adjuvant for clinical evaluation. Here, we discuss several aspects of current adjuvant research and strategies to better assess the complex pathways triggered by adjuvant candidates that can increase adjuvanticity and vaccine efficacy while minimizing reactogenicity. We propose a more systematic use of broad immunoprofiling, coupled with data integration using computational and mathematical modeling. This comprehensive evaluation of the host immune response will facilitate the selection of the most appropriate adjuvant for a vaccine, ultimately leading to the expeditious evaluation of novel adjuvants for vaccines against emerging infectious diseases, which will prove especially valuable during a pandemic where speed is of the essence when developing vaccines.
Keywords: Adjuvant; immunoprofiling; immunostimulators; reactogenicity.