Viravaxx exploits technology to convert immuno-dominant protein epitopes into potent antigens eliciting a strong IgG antibody response. The potential of the technology has originally been successfully demonstrated with a grass pollen allergen. Immuno-dominant peptides from these protein epitopes are fused to a carrier protein, PreS, originating from HBV. The number of peptide epitopes that can be fused to PreS are virtually unlimited: they can be isolated from different source proteins and can be freely combined.
A generalized structure of a PreS-based peptide carrier fusion protein is shown below:
Viravaxx’ technology is based on the so-called hapten carrier principle, where non-immunogenic haptens (small molecules or short peptides) can be positioned for elicitation of an IgG immune response. In this way, epitopes from coat proteins of the target virus, which in their natural environment are not detected by the immune system, can be made immunogenic. This allows to design vaccines across different serotypes by addressing invariant regions of the antigen required for receptor binding and virus entry.