VaxCelerate: the use of MTBhsp70-avidin as an adjuvant to rapidly generate self-assembling vaccines with biotinylated, antigen-specific peptides targeting emerging pathogens. (VAC6P.941)

Development of effective vaccines against emerging infectious diseases can take years to progress from pathogen isolation/identification to clinical approval. As a result, conventional approaches fail to produce field-ready vaccines before the EID has spread extensively. The VaxCelerate Project’s goal is to create a platform capable of generating and pre-clinically testing a new vaccine against specific pathogen targets in less than 120 days. A self-assembling vaccine, consisting of a fusion protein M. tuberculosis MTBhsp70 and avidin (MAV), is at the core of the approach. Mixing the MAV with biotinylated pathogen specific immunogenic peptides yields a self-assembled vaccine (SAV). To minimize the time required, we used a distributed R&D model involving experts in protein engineering, bioinformatics, peptide synthesis/design and GMP/GLP manufacturing and testing. This approach was first tested using ovalbumin in C57Bl/6 mice, Flu (H1N1) specific peptides, and ultimately a Lassa fever virus (LFV) specific vaccine in transgenic HLA DR3 mice. Using a GLP validated assay we demonstrated that the MAV assembled LFV induced significantly increased class II peptide specific interferon-CD4+ T cell responses in transgenic mice compared to peptide or MAV alone controls. The use of an identical design for each vaccine may facilitate accelerated regulatory review and by developing safety assessment tools that are more relevant to human vaccine responses than current preclinical models.