• Vaccine Name: Lassa fever Virus DNA Vaccine encoding GPC gene of LASV (Josiah Strain)
• Target Pathogen: Lassa Fever Virus
• Target Disease: Lassa fever
• Manufacturer: United States Army Medical Research Institute of Infectious diseases (USAMRIID)
• Type: DNA vaccine
• Status: Research
• Host Species for Licensed Use: None
• Antigen: Lassa Virus (Josiah Strain) GPC Gene (Cashman et al., 2017)
• GPC [Mopeia Lassa virus reassortant 29] gene engineering:
  • Type: DNA vaccine construction
  • Description:
  • Detailed Gene Information: Click Here.
• Preparation: GPC gene of LASV with post-translational cleavage of GPC into GP1 and GP2 in the host. (Cashman et al., 2017)
• Immunization Route: Intradermal injection (i.d.)

Macaque Response

• Vaccination Protocol: Cynomolgus macaques (NHP) were vaccinated by intradermal (ID) injection of the vaccine followed by ID-electroporation (EP). . Two separate studies were conducted to com- pare 3 or 2 vaccinations at 4-week intervals. (Cashman et al., 2017)
• Immune Response: Following exposure to LASV, neutralizing antibody levels increased in the LASV DNA-vaccinated NHP, peaking approximately 21 d post exposure, then declining slightly at the study end point. Initially, white blood cells (WBC) increased in the LASV DNA-vaccinated. Lymphocyte and monocyte populations increased rapidly after exposure in the LASV DNA-vaccinated NHP, stabilizing by day 21. Both hemoglobin and hematocrit increased before becoming stable in the LASV DNA-vaccinated NHP. Platelets increased in the LASV DNA-vaccinated NHP. (Cashman et al., 2017)
• Challenge Protocol: LASV Challenge
• Efficacy: To identify virus levels in the blood post-exposure, serum viremia was measured using a standard plaque assay as described. Neither serum viremia nor fever was observed in any of the LASV DNA-vaccinated NHP at any time-point. One NHP had one plaque present at the 1 £ 10¡1 dilution at day 6 which falls below the limit of quantitation for the assay and is considered a false positive. (Cashman et al., 2017)
• Description: All LASV-GPC DNA-vaccinated NHP, regardless of dose group, showed no signs of infection after exposure and survived to the study end point. Final morbidity scores were assigned at the study end point. A score of zero indicated the macaque was well; showing no outward signs of disease; whereas, a score of 10 indicated the NHP was severely ill and met euthanasia criteria. The LASV DNA-vaccinated NHP remained at zero on the morbidity scale for the duration of the study. (Cashman et al., 2017)