Development of a Marburg self-amplifying mRNA-lipid nanoparticle vaccine: differential effects when co-formulated with toll-like receptor agonists

ECI Vaccine IX 2024 -- Self-amplifying RNA (sa mRNA) formulated in lipid nanoparticles (LNPs) is a novel vaccine modality and is being used to develop a Marburg Virus vaccine comprising the Glycoprotein (MARV) sa mRNA. Toll-like receptor (TLR) agonists, which boost the innate immune response, have been used as adjuvants in subunit vaccines; however, it is uncertain as to whether these TLR agonists will provide adjuvanticity with the mRNA-LNP vaccines. To test the role of the TLR agonists, we have formulated MARV sa mRNA-LNPs encapsulating a CpG oligonucleotide (TLR-9 agonist), Telratolimod (TLR-7 agonist) or Monophosphoryl-lipid A (MPLA) (TLR-4 agonist).